5162 lines
150 KiB
C
5162 lines
150 KiB
C
/*
|
|
* linux/fs/ext4/inode.c
|
|
*
|
|
* Copyright (C) 1992, 1993, 1994, 1995
|
|
* Remy Card (card@masi.ibp.fr)
|
|
* Laboratoire MASI - Institut Blaise Pascal
|
|
* Universite Pierre et Marie Curie (Paris VI)
|
|
*
|
|
* from
|
|
*
|
|
* linux/fs/minix/inode.c
|
|
*
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
*
|
|
* 64-bit file support on 64-bit platforms by Jakub Jelinek
|
|
* (jj@sunsite.ms.mff.cuni.cz)
|
|
*
|
|
* Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/time.h>
|
|
#include <linux/jbd2.h>
|
|
#include <linux/highuid.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/quotaops.h>
|
|
#include <linux/string.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/writeback.h>
|
|
#include <linux/pagevec.h>
|
|
#include <linux/mpage.h>
|
|
#include <linux/namei.h>
|
|
#include <linux/uio.h>
|
|
#include <linux/bio.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/printk.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/ratelimit.h>
|
|
#include <linux/aio.h>
|
|
#include <linux/bitops.h>
|
|
|
|
#include "ext4_jbd2.h"
|
|
#include "xattr.h"
|
|
#include "acl.h"
|
|
#include "truncate.h"
|
|
|
|
#include <trace/events/ext4.h>
|
|
|
|
#define MPAGE_DA_EXTENT_TAIL 0x01
|
|
|
|
static __u32 ext4_inode_csum(struct inode *inode, struct ext4_inode *raw,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
__u16 csum_lo;
|
|
__u16 csum_hi = 0;
|
|
__u32 csum;
|
|
|
|
csum_lo = le16_to_cpu(raw->i_checksum_lo);
|
|
raw->i_checksum_lo = 0;
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
|
|
EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi)) {
|
|
csum_hi = le16_to_cpu(raw->i_checksum_hi);
|
|
raw->i_checksum_hi = 0;
|
|
}
|
|
|
|
csum = ext4_chksum(sbi, ei->i_csum_seed, (__u8 *)raw,
|
|
EXT4_INODE_SIZE(inode->i_sb));
|
|
|
|
raw->i_checksum_lo = cpu_to_le16(csum_lo);
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
|
|
EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
|
|
raw->i_checksum_hi = cpu_to_le16(csum_hi);
|
|
|
|
return csum;
|
|
}
|
|
|
|
static int ext4_inode_csum_verify(struct inode *inode, struct ext4_inode *raw,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
__u32 provided, calculated;
|
|
|
|
if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
|
|
cpu_to_le32(EXT4_OS_LINUX) ||
|
|
!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
|
|
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
|
|
return 1;
|
|
|
|
provided = le16_to_cpu(raw->i_checksum_lo);
|
|
calculated = ext4_inode_csum(inode, raw, ei);
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
|
|
EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
|
|
provided |= ((__u32)le16_to_cpu(raw->i_checksum_hi)) << 16;
|
|
else
|
|
calculated &= 0xFFFF;
|
|
|
|
return provided == calculated;
|
|
}
|
|
|
|
static void ext4_inode_csum_set(struct inode *inode, struct ext4_inode *raw,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
__u32 csum;
|
|
|
|
if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
|
|
cpu_to_le32(EXT4_OS_LINUX) ||
|
|
!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
|
|
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
|
|
return;
|
|
|
|
csum = ext4_inode_csum(inode, raw, ei);
|
|
raw->i_checksum_lo = cpu_to_le16(csum & 0xFFFF);
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE &&
|
|
EXT4_FITS_IN_INODE(raw, ei, i_checksum_hi))
|
|
raw->i_checksum_hi = cpu_to_le16(csum >> 16);
|
|
}
|
|
|
|
static inline int ext4_begin_ordered_truncate(struct inode *inode,
|
|
loff_t new_size)
|
|
{
|
|
trace_ext4_begin_ordered_truncate(inode, new_size);
|
|
/*
|
|
* If jinode is zero, then we never opened the file for
|
|
* writing, so there's no need to call
|
|
* jbd2_journal_begin_ordered_truncate() since there's no
|
|
* outstanding writes we need to flush.
|
|
*/
|
|
if (!EXT4_I(inode)->jinode)
|
|
return 0;
|
|
return jbd2_journal_begin_ordered_truncate(EXT4_JOURNAL(inode),
|
|
EXT4_I(inode)->jinode,
|
|
new_size);
|
|
}
|
|
|
|
static void ext4_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length);
|
|
static int __ext4_journalled_writepage(struct page *page, unsigned int len);
|
|
static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh);
|
|
static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
|
|
int pextents);
|
|
|
|
/*
|
|
* Test whether an inode is a fast symlink.
|
|
*/
|
|
static int ext4_inode_is_fast_symlink(struct inode *inode)
|
|
{
|
|
int ea_blocks = EXT4_I(inode)->i_file_acl ?
|
|
EXT4_CLUSTER_SIZE(inode->i_sb) >> 9 : 0;
|
|
|
|
return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
|
|
}
|
|
|
|
/*
|
|
* Restart the transaction associated with *handle. This does a commit,
|
|
* so before we call here everything must be consistently dirtied against
|
|
* this transaction.
|
|
*/
|
|
int ext4_truncate_restart_trans(handle_t *handle, struct inode *inode,
|
|
int nblocks)
|
|
{
|
|
int ret;
|
|
|
|
/*
|
|
* Drop i_data_sem to avoid deadlock with ext4_map_blocks. At this
|
|
* moment, get_block can be called only for blocks inside i_size since
|
|
* page cache has been already dropped and writes are blocked by
|
|
* i_mutex. So we can safely drop the i_data_sem here.
|
|
*/
|
|
BUG_ON(EXT4_JOURNAL(inode) == NULL);
|
|
jbd_debug(2, "restarting handle %p\n", handle);
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
ret = ext4_journal_restart(handle, nblocks);
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
ext4_discard_preallocations(inode);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Called at the last iput() if i_nlink is zero.
|
|
*/
|
|
void ext4_evict_inode(struct inode *inode)
|
|
{
|
|
handle_t *handle;
|
|
int err;
|
|
|
|
trace_ext4_evict_inode(inode);
|
|
|
|
if (inode->i_nlink) {
|
|
/*
|
|
* When journalling data dirty buffers are tracked only in the
|
|
* journal. So although mm thinks everything is clean and
|
|
* ready for reaping the inode might still have some pages to
|
|
* write in the running transaction or waiting to be
|
|
* checkpointed. Thus calling jbd2_journal_invalidatepage()
|
|
* (via truncate_inode_pages()) to discard these buffers can
|
|
* cause data loss. Also even if we did not discard these
|
|
* buffers, we would have no way to find them after the inode
|
|
* is reaped and thus user could see stale data if he tries to
|
|
* read them before the transaction is checkpointed. So be
|
|
* careful and force everything to disk here... We use
|
|
* ei->i_datasync_tid to store the newest transaction
|
|
* containing inode's data.
|
|
*
|
|
* Note that directories do not have this problem because they
|
|
* don't use page cache.
|
|
*/
|
|
if (ext4_should_journal_data(inode) &&
|
|
(S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) &&
|
|
inode->i_ino != EXT4_JOURNAL_INO) {
|
|
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
|
|
tid_t commit_tid = EXT4_I(inode)->i_datasync_tid;
|
|
|
|
jbd2_complete_transaction(journal, commit_tid);
|
|
filemap_write_and_wait(&inode->i_data);
|
|
}
|
|
truncate_inode_pages(&inode->i_data, 0);
|
|
|
|
WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
|
|
goto no_delete;
|
|
}
|
|
|
|
if (!is_bad_inode(inode))
|
|
dquot_initialize(inode);
|
|
|
|
if (ext4_should_order_data(inode))
|
|
ext4_begin_ordered_truncate(inode, 0);
|
|
truncate_inode_pages(&inode->i_data, 0);
|
|
|
|
WARN_ON(atomic_read(&EXT4_I(inode)->i_ioend_count));
|
|
if (is_bad_inode(inode))
|
|
goto no_delete;
|
|
|
|
/*
|
|
* Protect us against freezing - iput() caller didn't have to have any
|
|
* protection against it
|
|
*/
|
|
sb_start_intwrite(inode->i_sb);
|
|
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
|
|
ext4_blocks_for_truncate(inode)+3);
|
|
if (IS_ERR(handle)) {
|
|
ext4_std_error(inode->i_sb, PTR_ERR(handle));
|
|
/*
|
|
* If we're going to skip the normal cleanup, we still need to
|
|
* make sure that the in-core orphan linked list is properly
|
|
* cleaned up.
|
|
*/
|
|
ext4_orphan_del(NULL, inode);
|
|
sb_end_intwrite(inode->i_sb);
|
|
goto no_delete;
|
|
}
|
|
|
|
if (IS_SYNC(inode))
|
|
ext4_handle_sync(handle);
|
|
inode->i_size = 0;
|
|
err = ext4_mark_inode_dirty(handle, inode);
|
|
if (err) {
|
|
ext4_warning(inode->i_sb,
|
|
"couldn't mark inode dirty (err %d)", err);
|
|
goto stop_handle;
|
|
}
|
|
if (inode->i_blocks)
|
|
ext4_truncate(inode);
|
|
|
|
/*
|
|
* ext4_ext_truncate() doesn't reserve any slop when it
|
|
* restarts journal transactions; therefore there may not be
|
|
* enough credits left in the handle to remove the inode from
|
|
* the orphan list and set the dtime field.
|
|
*/
|
|
if (!ext4_handle_has_enough_credits(handle, 3)) {
|
|
err = ext4_journal_extend(handle, 3);
|
|
if (err > 0)
|
|
err = ext4_journal_restart(handle, 3);
|
|
if (err != 0) {
|
|
ext4_warning(inode->i_sb,
|
|
"couldn't extend journal (err %d)", err);
|
|
stop_handle:
|
|
ext4_journal_stop(handle);
|
|
ext4_orphan_del(NULL, inode);
|
|
sb_end_intwrite(inode->i_sb);
|
|
goto no_delete;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Kill off the orphan record which ext4_truncate created.
|
|
* AKPM: I think this can be inside the above `if'.
|
|
* Note that ext4_orphan_del() has to be able to cope with the
|
|
* deletion of a non-existent orphan - this is because we don't
|
|
* know if ext4_truncate() actually created an orphan record.
|
|
* (Well, we could do this if we need to, but heck - it works)
|
|
*/
|
|
ext4_orphan_del(handle, inode);
|
|
EXT4_I(inode)->i_dtime = get_seconds();
|
|
|
|
/*
|
|
* One subtle ordering requirement: if anything has gone wrong
|
|
* (transaction abort, IO errors, whatever), then we can still
|
|
* do these next steps (the fs will already have been marked as
|
|
* having errors), but we can't free the inode if the mark_dirty
|
|
* fails.
|
|
*/
|
|
if (ext4_mark_inode_dirty(handle, inode))
|
|
/* If that failed, just do the required in-core inode clear. */
|
|
ext4_clear_inode(inode);
|
|
else
|
|
ext4_free_inode(handle, inode);
|
|
ext4_journal_stop(handle);
|
|
sb_end_intwrite(inode->i_sb);
|
|
return;
|
|
no_delete:
|
|
ext4_clear_inode(inode); /* We must guarantee clearing of inode... */
|
|
}
|
|
|
|
#ifdef CONFIG_QUOTA
|
|
qsize_t *ext4_get_reserved_space(struct inode *inode)
|
|
{
|
|
return &EXT4_I(inode)->i_reserved_quota;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Calculate the number of metadata blocks need to reserve
|
|
* to allocate a block located at @lblock
|
|
*/
|
|
static int ext4_calc_metadata_amount(struct inode *inode, ext4_lblk_t lblock)
|
|
{
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
return ext4_ext_calc_metadata_amount(inode, lblock);
|
|
|
|
return ext4_ind_calc_metadata_amount(inode, lblock);
|
|
}
|
|
|
|
/*
|
|
* Called with i_data_sem down, which is important since we can call
|
|
* ext4_discard_preallocations() from here.
|
|
*/
|
|
void ext4_da_update_reserve_space(struct inode *inode,
|
|
int used, int quota_claim)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
|
|
spin_lock(&ei->i_block_reservation_lock);
|
|
trace_ext4_da_update_reserve_space(inode, used, quota_claim);
|
|
if (unlikely(used > ei->i_reserved_data_blocks)) {
|
|
ext4_warning(inode->i_sb, "%s: ino %lu, used %d "
|
|
"with only %d reserved data blocks",
|
|
__func__, inode->i_ino, used,
|
|
ei->i_reserved_data_blocks);
|
|
WARN_ON(1);
|
|
used = ei->i_reserved_data_blocks;
|
|
}
|
|
|
|
if (unlikely(ei->i_allocated_meta_blocks > ei->i_reserved_meta_blocks)) {
|
|
ext4_warning(inode->i_sb, "ino %lu, allocated %d "
|
|
"with only %d reserved metadata blocks "
|
|
"(releasing %d blocks with reserved %d data blocks)",
|
|
inode->i_ino, ei->i_allocated_meta_blocks,
|
|
ei->i_reserved_meta_blocks, used,
|
|
ei->i_reserved_data_blocks);
|
|
WARN_ON(1);
|
|
ei->i_allocated_meta_blocks = ei->i_reserved_meta_blocks;
|
|
}
|
|
|
|
/* Update per-inode reservations */
|
|
ei->i_reserved_data_blocks -= used;
|
|
ei->i_reserved_meta_blocks -= ei->i_allocated_meta_blocks;
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter,
|
|
used + ei->i_allocated_meta_blocks);
|
|
ei->i_allocated_meta_blocks = 0;
|
|
|
|
if (ei->i_reserved_data_blocks == 0) {
|
|
/*
|
|
* We can release all of the reserved metadata blocks
|
|
* only when we have written all of the delayed
|
|
* allocation blocks.
|
|
*/
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter,
|
|
ei->i_reserved_meta_blocks);
|
|
ei->i_reserved_meta_blocks = 0;
|
|
ei->i_da_metadata_calc_len = 0;
|
|
}
|
|
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
|
/* Update quota subsystem for data blocks */
|
|
if (quota_claim)
|
|
dquot_claim_block(inode, EXT4_C2B(sbi, used));
|
|
else {
|
|
/*
|
|
* We did fallocate with an offset that is already delayed
|
|
* allocated. So on delayed allocated writeback we should
|
|
* not re-claim the quota for fallocated blocks.
|
|
*/
|
|
dquot_release_reservation_block(inode, EXT4_C2B(sbi, used));
|
|
}
|
|
|
|
/*
|
|
* If we have done all the pending block allocations and if
|
|
* there aren't any writers on the inode, we can discard the
|
|
* inode's preallocations.
|
|
*/
|
|
if ((ei->i_reserved_data_blocks == 0) &&
|
|
(atomic_read(&inode->i_writecount) == 0))
|
|
ext4_discard_preallocations(inode);
|
|
}
|
|
|
|
static int __check_block_validity(struct inode *inode, const char *func,
|
|
unsigned int line,
|
|
struct ext4_map_blocks *map)
|
|
{
|
|
if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), map->m_pblk,
|
|
map->m_len)) {
|
|
ext4_error_inode(inode, func, line, map->m_pblk,
|
|
"lblock %lu mapped to illegal pblock "
|
|
"(length %d)", (unsigned long) map->m_lblk,
|
|
map->m_len);
|
|
return -EIO;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#define check_block_validity(inode, map) \
|
|
__check_block_validity((inode), __func__, __LINE__, (map))
|
|
|
|
#ifdef ES_AGGRESSIVE_TEST
|
|
static void ext4_map_blocks_es_recheck(handle_t *handle,
|
|
struct inode *inode,
|
|
struct ext4_map_blocks *es_map,
|
|
struct ext4_map_blocks *map,
|
|
int flags)
|
|
{
|
|
int retval;
|
|
|
|
map->m_flags = 0;
|
|
/*
|
|
* There is a race window that the result is not the same.
|
|
* e.g. xfstests #223 when dioread_nolock enables. The reason
|
|
* is that we lookup a block mapping in extent status tree with
|
|
* out taking i_data_sem. So at the time the unwritten extent
|
|
* could be converted.
|
|
*/
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
retval = ext4_ext_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
} else {
|
|
retval = ext4_ind_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
}
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
up_read((&EXT4_I(inode)->i_data_sem));
|
|
/*
|
|
* Clear EXT4_MAP_FROM_CLUSTER and EXT4_MAP_BOUNDARY flag
|
|
* because it shouldn't be marked in es_map->m_flags.
|
|
*/
|
|
map->m_flags &= ~(EXT4_MAP_FROM_CLUSTER | EXT4_MAP_BOUNDARY);
|
|
|
|
/*
|
|
* We don't check m_len because extent will be collpased in status
|
|
* tree. So the m_len might not equal.
|
|
*/
|
|
if (es_map->m_lblk != map->m_lblk ||
|
|
es_map->m_flags != map->m_flags ||
|
|
es_map->m_pblk != map->m_pblk) {
|
|
printk("ES cache assertion failed for inode: %lu "
|
|
"es_cached ex [%d/%d/%llu/%x] != "
|
|
"found ex [%d/%d/%llu/%x] retval %d flags %x\n",
|
|
inode->i_ino, es_map->m_lblk, es_map->m_len,
|
|
es_map->m_pblk, es_map->m_flags, map->m_lblk,
|
|
map->m_len, map->m_pblk, map->m_flags,
|
|
retval, flags);
|
|
}
|
|
}
|
|
#endif /* ES_AGGRESSIVE_TEST */
|
|
|
|
/*
|
|
* The ext4_map_blocks() function tries to look up the requested blocks,
|
|
* and returns if the blocks are already mapped.
|
|
*
|
|
* Otherwise it takes the write lock of the i_data_sem and allocate blocks
|
|
* and store the allocated blocks in the result buffer head and mark it
|
|
* mapped.
|
|
*
|
|
* If file type is extents based, it will call ext4_ext_map_blocks(),
|
|
* Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
|
|
* based files
|
|
*
|
|
* On success, it returns the number of blocks being mapped or allocate.
|
|
* if create==0 and the blocks are pre-allocated and uninitialized block,
|
|
* the result buffer head is unmapped. If the create ==1, it will make sure
|
|
* the buffer head is mapped.
|
|
*
|
|
* It returns 0 if plain look up failed (blocks have not been allocated), in
|
|
* that case, buffer head is unmapped
|
|
*
|
|
* It returns the error in case of allocation failure.
|
|
*/
|
|
int ext4_map_blocks(handle_t *handle, struct inode *inode,
|
|
struct ext4_map_blocks *map, int flags)
|
|
{
|
|
struct extent_status es;
|
|
int retval;
|
|
#ifdef ES_AGGRESSIVE_TEST
|
|
struct ext4_map_blocks orig_map;
|
|
|
|
memcpy(&orig_map, map, sizeof(*map));
|
|
#endif
|
|
|
|
map->m_flags = 0;
|
|
ext_debug("ext4_map_blocks(): inode %lu, flag %d, max_blocks %u,"
|
|
"logical block %lu\n", inode->i_ino, flags, map->m_len,
|
|
(unsigned long) map->m_lblk);
|
|
|
|
/* Lookup extent status tree firstly */
|
|
if (ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
|
|
ext4_es_lru_add(inode);
|
|
if (ext4_es_is_written(&es) || ext4_es_is_unwritten(&es)) {
|
|
map->m_pblk = ext4_es_pblock(&es) +
|
|
map->m_lblk - es.es_lblk;
|
|
map->m_flags |= ext4_es_is_written(&es) ?
|
|
EXT4_MAP_MAPPED : EXT4_MAP_UNWRITTEN;
|
|
retval = es.es_len - (map->m_lblk - es.es_lblk);
|
|
if (retval > map->m_len)
|
|
retval = map->m_len;
|
|
map->m_len = retval;
|
|
} else if (ext4_es_is_delayed(&es) || ext4_es_is_hole(&es)) {
|
|
retval = 0;
|
|
} else {
|
|
BUG_ON(1);
|
|
}
|
|
#ifdef ES_AGGRESSIVE_TEST
|
|
ext4_map_blocks_es_recheck(handle, inode, map,
|
|
&orig_map, flags);
|
|
#endif
|
|
goto found;
|
|
}
|
|
|
|
/*
|
|
* Try to see if we can get the block without requesting a new
|
|
* file system block.
|
|
*/
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
retval = ext4_ext_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
} else {
|
|
retval = ext4_ind_map_blocks(handle, inode, map, flags &
|
|
EXT4_GET_BLOCKS_KEEP_SIZE);
|
|
}
|
|
if (retval > 0) {
|
|
int ret;
|
|
unsigned int status;
|
|
|
|
if (unlikely(retval != map->m_len)) {
|
|
ext4_warning(inode->i_sb,
|
|
"ES len assertion failed for inode "
|
|
"%lu: retval %d != map->m_len %d",
|
|
inode->i_ino, retval, map->m_len);
|
|
WARN_ON(1);
|
|
}
|
|
|
|
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
|
|
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
|
|
if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
|
|
ext4_find_delalloc_range(inode, map->m_lblk,
|
|
map->m_lblk + map->m_len - 1))
|
|
status |= EXTENT_STATUS_DELAYED;
|
|
ret = ext4_es_insert_extent(inode, map->m_lblk,
|
|
map->m_len, map->m_pblk, status);
|
|
if (ret < 0)
|
|
retval = ret;
|
|
}
|
|
if (!(flags & EXT4_GET_BLOCKS_NO_LOCK))
|
|
up_read((&EXT4_I(inode)->i_data_sem));
|
|
|
|
found:
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
|
|
int ret = check_block_validity(inode, map);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
|
|
/* If it is only a block(s) look up */
|
|
if ((flags & EXT4_GET_BLOCKS_CREATE) == 0)
|
|
return retval;
|
|
|
|
/*
|
|
* Returns if the blocks have already allocated
|
|
*
|
|
* Note that if blocks have been preallocated
|
|
* ext4_ext_get_block() returns the create = 0
|
|
* with buffer head unmapped.
|
|
*/
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED)
|
|
return retval;
|
|
|
|
/*
|
|
* Here we clear m_flags because after allocating an new extent,
|
|
* it will be set again.
|
|
*/
|
|
map->m_flags &= ~EXT4_MAP_FLAGS;
|
|
|
|
/*
|
|
* New blocks allocate and/or writing to uninitialized extent
|
|
* will possibly result in updating i_data, so we take
|
|
* the write lock of i_data_sem, and call get_blocks()
|
|
* with create == 1 flag.
|
|
*/
|
|
down_write((&EXT4_I(inode)->i_data_sem));
|
|
|
|
/*
|
|
* if the caller is from delayed allocation writeout path
|
|
* we have already reserved fs blocks for allocation
|
|
* let the underlying get_block() function know to
|
|
* avoid double accounting
|
|
*/
|
|
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
|
|
ext4_set_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
|
|
/*
|
|
* We need to check for EXT4 here because migrate
|
|
* could have changed the inode type in between
|
|
*/
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
retval = ext4_ext_map_blocks(handle, inode, map, flags);
|
|
} else {
|
|
retval = ext4_ind_map_blocks(handle, inode, map, flags);
|
|
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_NEW) {
|
|
/*
|
|
* We allocated new blocks which will result in
|
|
* i_data's format changing. Force the migrate
|
|
* to fail by clearing migrate flags
|
|
*/
|
|
ext4_clear_inode_state(inode, EXT4_STATE_EXT_MIGRATE);
|
|
}
|
|
|
|
/*
|
|
* Update reserved blocks/metadata blocks after successful
|
|
* block allocation which had been deferred till now. We don't
|
|
* support fallocate for non extent files. So we can update
|
|
* reserve space here.
|
|
*/
|
|
if ((retval > 0) &&
|
|
(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE))
|
|
ext4_da_update_reserve_space(inode, retval, 1);
|
|
}
|
|
if (flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE)
|
|
ext4_clear_inode_state(inode, EXT4_STATE_DELALLOC_RESERVED);
|
|
|
|
if (retval > 0) {
|
|
int ret;
|
|
unsigned int status;
|
|
|
|
if (unlikely(retval != map->m_len)) {
|
|
ext4_warning(inode->i_sb,
|
|
"ES len assertion failed for inode "
|
|
"%lu: retval %d != map->m_len %d",
|
|
inode->i_ino, retval, map->m_len);
|
|
WARN_ON(1);
|
|
}
|
|
|
|
/*
|
|
* If the extent has been zeroed out, we don't need to update
|
|
* extent status tree.
|
|
*/
|
|
if ((flags & EXT4_GET_BLOCKS_PRE_IO) &&
|
|
ext4_es_lookup_extent(inode, map->m_lblk, &es)) {
|
|
if (ext4_es_is_written(&es))
|
|
goto has_zeroout;
|
|
}
|
|
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
|
|
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
|
|
if (!(flags & EXT4_GET_BLOCKS_DELALLOC_RESERVE) &&
|
|
ext4_find_delalloc_range(inode, map->m_lblk,
|
|
map->m_lblk + map->m_len - 1))
|
|
status |= EXTENT_STATUS_DELAYED;
|
|
ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
|
|
map->m_pblk, status);
|
|
if (ret < 0)
|
|
retval = ret;
|
|
}
|
|
|
|
has_zeroout:
|
|
up_write((&EXT4_I(inode)->i_data_sem));
|
|
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
|
|
int ret = check_block_validity(inode, map);
|
|
if (ret != 0)
|
|
return ret;
|
|
}
|
|
return retval;
|
|
}
|
|
|
|
/* Maximum number of blocks we map for direct IO at once. */
|
|
#define DIO_MAX_BLOCKS 4096
|
|
|
|
static int _ext4_get_block(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int flags)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct ext4_map_blocks map;
|
|
int ret = 0, started = 0;
|
|
int dio_credits;
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
return -ERANGE;
|
|
|
|
map.m_lblk = iblock;
|
|
map.m_len = bh->b_size >> inode->i_blkbits;
|
|
|
|
if (flags && !(flags & EXT4_GET_BLOCKS_NO_LOCK) && !handle) {
|
|
/* Direct IO write... */
|
|
if (map.m_len > DIO_MAX_BLOCKS)
|
|
map.m_len = DIO_MAX_BLOCKS;
|
|
dio_credits = ext4_chunk_trans_blocks(inode, map.m_len);
|
|
handle = ext4_journal_start(inode, EXT4_HT_MAP_BLOCKS,
|
|
dio_credits);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
return ret;
|
|
}
|
|
started = 1;
|
|
}
|
|
|
|
ret = ext4_map_blocks(handle, inode, &map, flags);
|
|
if (ret > 0) {
|
|
ext4_io_end_t *io_end = ext4_inode_aio(inode);
|
|
|
|
map_bh(bh, inode->i_sb, map.m_pblk);
|
|
bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
|
|
if (io_end && io_end->flag & EXT4_IO_END_UNWRITTEN)
|
|
set_buffer_defer_completion(bh);
|
|
bh->b_size = inode->i_sb->s_blocksize * map.m_len;
|
|
ret = 0;
|
|
}
|
|
if (started)
|
|
ext4_journal_stop(handle);
|
|
return ret;
|
|
}
|
|
|
|
int ext4_get_block(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int create)
|
|
{
|
|
return _ext4_get_block(inode, iblock, bh,
|
|
create ? EXT4_GET_BLOCKS_CREATE : 0);
|
|
}
|
|
|
|
/*
|
|
* `handle' can be NULL if create is zero
|
|
*/
|
|
struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
|
|
ext4_lblk_t block, int create, int *errp)
|
|
{
|
|
struct ext4_map_blocks map;
|
|
struct buffer_head *bh;
|
|
int fatal = 0, err;
|
|
|
|
J_ASSERT(handle != NULL || create == 0);
|
|
|
|
map.m_lblk = block;
|
|
map.m_len = 1;
|
|
err = ext4_map_blocks(handle, inode, &map,
|
|
create ? EXT4_GET_BLOCKS_CREATE : 0);
|
|
|
|
/* ensure we send some value back into *errp */
|
|
*errp = 0;
|
|
|
|
if (create && err == 0)
|
|
err = -ENOSPC; /* should never happen */
|
|
if (err < 0)
|
|
*errp = err;
|
|
if (err <= 0)
|
|
return NULL;
|
|
|
|
bh = sb_getblk(inode->i_sb, map.m_pblk);
|
|
if (unlikely(!bh)) {
|
|
*errp = -ENOMEM;
|
|
return NULL;
|
|
}
|
|
if (map.m_flags & EXT4_MAP_NEW) {
|
|
J_ASSERT(create != 0);
|
|
J_ASSERT(handle != NULL);
|
|
|
|
/*
|
|
* Now that we do not always journal data, we should
|
|
* keep in mind whether this should always journal the
|
|
* new buffer as metadata. For now, regular file
|
|
* writes use ext4_get_block instead, so it's not a
|
|
* problem.
|
|
*/
|
|
lock_buffer(bh);
|
|
BUFFER_TRACE(bh, "call get_create_access");
|
|
fatal = ext4_journal_get_create_access(handle, bh);
|
|
if (!fatal && !buffer_uptodate(bh)) {
|
|
memset(bh->b_data, 0, inode->i_sb->s_blocksize);
|
|
set_buffer_uptodate(bh);
|
|
}
|
|
unlock_buffer(bh);
|
|
BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
|
|
err = ext4_handle_dirty_metadata(handle, inode, bh);
|
|
if (!fatal)
|
|
fatal = err;
|
|
} else {
|
|
BUFFER_TRACE(bh, "not a new buffer");
|
|
}
|
|
if (fatal) {
|
|
*errp = fatal;
|
|
brelse(bh);
|
|
bh = NULL;
|
|
}
|
|
return bh;
|
|
}
|
|
|
|
struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
|
|
ext4_lblk_t block, int create, int *err)
|
|
{
|
|
struct buffer_head *bh;
|
|
|
|
bh = ext4_getblk(handle, inode, block, create, err);
|
|
if (!bh)
|
|
return bh;
|
|
if (buffer_uptodate(bh))
|
|
return bh;
|
|
ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
if (buffer_uptodate(bh))
|
|
return bh;
|
|
put_bh(bh);
|
|
*err = -EIO;
|
|
return NULL;
|
|
}
|
|
|
|
int ext4_walk_page_buffers(handle_t *handle,
|
|
struct buffer_head *head,
|
|
unsigned from,
|
|
unsigned to,
|
|
int *partial,
|
|
int (*fn)(handle_t *handle,
|
|
struct buffer_head *bh))
|
|
{
|
|
struct buffer_head *bh;
|
|
unsigned block_start, block_end;
|
|
unsigned blocksize = head->b_size;
|
|
int err, ret = 0;
|
|
struct buffer_head *next;
|
|
|
|
for (bh = head, block_start = 0;
|
|
ret == 0 && (bh != head || !block_start);
|
|
block_start = block_end, bh = next) {
|
|
next = bh->b_this_page;
|
|
block_end = block_start + blocksize;
|
|
if (block_end <= from || block_start >= to) {
|
|
if (partial && !buffer_uptodate(bh))
|
|
*partial = 1;
|
|
continue;
|
|
}
|
|
err = (*fn)(handle, bh);
|
|
if (!ret)
|
|
ret = err;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* To preserve ordering, it is essential that the hole instantiation and
|
|
* the data write be encapsulated in a single transaction. We cannot
|
|
* close off a transaction and start a new one between the ext4_get_block()
|
|
* and the commit_write(). So doing the jbd2_journal_start at the start of
|
|
* prepare_write() is the right place.
|
|
*
|
|
* Also, this function can nest inside ext4_writepage(). In that case, we
|
|
* *know* that ext4_writepage() has generated enough buffer credits to do the
|
|
* whole page. So we won't block on the journal in that case, which is good,
|
|
* because the caller may be PF_MEMALLOC.
|
|
*
|
|
* By accident, ext4 can be reentered when a transaction is open via
|
|
* quota file writes. If we were to commit the transaction while thus
|
|
* reentered, there can be a deadlock - we would be holding a quota
|
|
* lock, and the commit would never complete if another thread had a
|
|
* transaction open and was blocking on the quota lock - a ranking
|
|
* violation.
|
|
*
|
|
* So what we do is to rely on the fact that jbd2_journal_stop/journal_start
|
|
* will _not_ run commit under these circumstances because handle->h_ref
|
|
* is elevated. We'll still have enough credits for the tiny quotafile
|
|
* write.
|
|
*/
|
|
int do_journal_get_write_access(handle_t *handle,
|
|
struct buffer_head *bh)
|
|
{
|
|
int dirty = buffer_dirty(bh);
|
|
int ret;
|
|
|
|
if (!buffer_mapped(bh) || buffer_freed(bh))
|
|
return 0;
|
|
/*
|
|
* __block_write_begin() could have dirtied some buffers. Clean
|
|
* the dirty bit as jbd2_journal_get_write_access() could complain
|
|
* otherwise about fs integrity issues. Setting of the dirty bit
|
|
* by __block_write_begin() isn't a real problem here as we clear
|
|
* the bit before releasing a page lock and thus writeback cannot
|
|
* ever write the buffer.
|
|
*/
|
|
if (dirty)
|
|
clear_buffer_dirty(bh);
|
|
ret = ext4_journal_get_write_access(handle, bh);
|
|
if (!ret && dirty)
|
|
ret = ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
return ret;
|
|
}
|
|
|
|
static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create);
|
|
static int ext4_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
int ret, needed_blocks;
|
|
handle_t *handle;
|
|
int retries = 0;
|
|
struct page *page;
|
|
pgoff_t index;
|
|
unsigned from, to;
|
|
|
|
trace_ext4_write_begin(inode, pos, len, flags);
|
|
/*
|
|
* Reserve one block more for addition to orphan list in case
|
|
* we allocate blocks but write fails for some reason
|
|
*/
|
|
needed_blocks = ext4_writepage_trans_blocks(inode) + 1;
|
|
index = pos >> PAGE_CACHE_SHIFT;
|
|
from = pos & (PAGE_CACHE_SIZE - 1);
|
|
to = from + len;
|
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
|
|
ret = ext4_try_to_write_inline_data(mapping, inode, pos, len,
|
|
flags, pagep);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (ret == 1)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* grab_cache_page_write_begin() can take a long time if the
|
|
* system is thrashing due to memory pressure, or if the page
|
|
* is being written back. So grab it first before we start
|
|
* the transaction handle. This also allows us to allocate
|
|
* the page (if needed) without using GFP_NOFS.
|
|
*/
|
|
retry_grab:
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
unlock_page(page);
|
|
|
|
retry_journal:
|
|
handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
|
|
if (IS_ERR(handle)) {
|
|
page_cache_release(page);
|
|
return PTR_ERR(handle);
|
|
}
|
|
|
|
lock_page(page);
|
|
if (page->mapping != mapping) {
|
|
/* The page got truncated from under us */
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
ext4_journal_stop(handle);
|
|
goto retry_grab;
|
|
}
|
|
/* In case writeback began while the page was unlocked */
|
|
wait_for_stable_page(page);
|
|
|
|
if (ext4_should_dioread_nolock(inode))
|
|
ret = __block_write_begin(page, pos, len, ext4_get_block_write);
|
|
else
|
|
ret = __block_write_begin(page, pos, len, ext4_get_block);
|
|
|
|
if (!ret && ext4_should_journal_data(inode)) {
|
|
ret = ext4_walk_page_buffers(handle, page_buffers(page),
|
|
from, to, NULL,
|
|
do_journal_get_write_access);
|
|
}
|
|
|
|
if (ret) {
|
|
unlock_page(page);
|
|
/*
|
|
* __block_write_begin may have instantiated a few blocks
|
|
* outside i_size. Trim these off again. Don't need
|
|
* i_size_read because we hold i_mutex.
|
|
*
|
|
* Add inode to orphan list in case we crash before
|
|
* truncate finishes
|
|
*/
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
ext4_orphan_add(handle, inode);
|
|
|
|
ext4_journal_stop(handle);
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might
|
|
* still be on the orphan list; we need to
|
|
* make sure the inode is removed from the
|
|
* orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
if (ret == -ENOSPC &&
|
|
ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry_journal;
|
|
page_cache_release(page);
|
|
return ret;
|
|
}
|
|
*pagep = page;
|
|
return ret;
|
|
}
|
|
|
|
/* For write_end() in data=journal mode */
|
|
static int write_end_fn(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
int ret;
|
|
if (!buffer_mapped(bh) || buffer_freed(bh))
|
|
return 0;
|
|
set_buffer_uptodate(bh);
|
|
ret = ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
clear_buffer_meta(bh);
|
|
clear_buffer_prio(bh);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* We need to pick up the new inode size which generic_commit_write gave us
|
|
* `file' can be NULL - eg, when called from page_symlink().
|
|
*
|
|
* ext4 never places buffers on inode->i_mapping->private_list. metadata
|
|
* buffers are managed internally.
|
|
*/
|
|
static int ext4_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
int i_size_changed = 0;
|
|
|
|
trace_ext4_write_end(inode, pos, len, copied);
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_ORDERED_MODE)) {
|
|
ret = ext4_jbd2_file_inode(handle, inode);
|
|
if (ret) {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
goto errout;
|
|
}
|
|
}
|
|
|
|
if (ext4_has_inline_data(inode)) {
|
|
ret = ext4_write_inline_data_end(inode, pos, len,
|
|
copied, page);
|
|
if (ret < 0)
|
|
goto errout;
|
|
copied = ret;
|
|
} else
|
|
copied = block_write_end(file, mapping, pos,
|
|
len, copied, page, fsdata);
|
|
|
|
/*
|
|
* No need to use i_size_read() here, the i_size
|
|
* cannot change under us because we hole i_mutex.
|
|
*
|
|
* But it's important to update i_size while still holding page lock:
|
|
* page writeout could otherwise come in and zero beyond i_size.
|
|
*/
|
|
if (pos + copied > inode->i_size) {
|
|
i_size_write(inode, pos + copied);
|
|
i_size_changed = 1;
|
|
}
|
|
|
|
if (pos + copied > EXT4_I(inode)->i_disksize) {
|
|
/* We need to mark inode dirty even if
|
|
* new_i_size is less that inode->i_size
|
|
* but greater than i_disksize. (hint delalloc)
|
|
*/
|
|
ext4_update_i_disksize(inode, (pos + copied));
|
|
i_size_changed = 1;
|
|
}
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
/*
|
|
* Don't mark the inode dirty under page lock. First, it unnecessarily
|
|
* makes the holding time of page lock longer. Second, it forces lock
|
|
* ordering of page lock and transaction start for journaling
|
|
* filesystems.
|
|
*/
|
|
if (i_size_changed)
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
/* if we have allocated more blocks and copied
|
|
* less. We will have blocks allocated outside
|
|
* inode->i_size. So truncate them
|
|
*/
|
|
ext4_orphan_add(handle, inode);
|
|
errout:
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might still be
|
|
* on the orphan list; we need to make sure the inode
|
|
* is removed from the orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
static int ext4_journalled_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
int partial = 0;
|
|
unsigned from, to;
|
|
loff_t new_i_size;
|
|
|
|
trace_ext4_journalled_write_end(inode, pos, len, copied);
|
|
from = pos & (PAGE_CACHE_SIZE - 1);
|
|
to = from + len;
|
|
|
|
BUG_ON(!ext4_handle_valid(handle));
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
copied = ext4_write_inline_data_end(inode, pos, len,
|
|
copied, page);
|
|
else {
|
|
if (copied < len) {
|
|
if (!PageUptodate(page))
|
|
copied = 0;
|
|
page_zero_new_buffers(page, from+copied, to);
|
|
}
|
|
|
|
ret = ext4_walk_page_buffers(handle, page_buffers(page), from,
|
|
to, &partial, write_end_fn);
|
|
if (!partial)
|
|
SetPageUptodate(page);
|
|
}
|
|
new_i_size = pos + copied;
|
|
if (new_i_size > inode->i_size)
|
|
i_size_write(inode, pos+copied);
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
|
|
if (new_i_size > EXT4_I(inode)->i_disksize) {
|
|
ext4_update_i_disksize(inode, new_i_size);
|
|
ret2 = ext4_mark_inode_dirty(handle, inode);
|
|
if (!ret)
|
|
ret = ret2;
|
|
}
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
if (pos + len > inode->i_size && ext4_can_truncate(inode))
|
|
/* if we have allocated more blocks and copied
|
|
* less. We will have blocks allocated outside
|
|
* inode->i_size. So truncate them
|
|
*/
|
|
ext4_orphan_add(handle, inode);
|
|
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
if (pos + len > inode->i_size) {
|
|
ext4_truncate_failed_write(inode);
|
|
/*
|
|
* If truncate failed early the inode might still be
|
|
* on the orphan list; we need to make sure the inode
|
|
* is removed from the orphan list in that case.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
}
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
/*
|
|
* Reserve a metadata for a single block located at lblock
|
|
*/
|
|
static int ext4_da_reserve_metadata(struct inode *inode, ext4_lblk_t lblock)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
unsigned int md_needed;
|
|
ext4_lblk_t save_last_lblock;
|
|
int save_len;
|
|
|
|
/*
|
|
* recalculate the amount of metadata blocks to reserve
|
|
* in order to allocate nrblocks
|
|
* worse case is one extent per block
|
|
*/
|
|
spin_lock(&ei->i_block_reservation_lock);
|
|
/*
|
|
* ext4_calc_metadata_amount() has side effects, which we have
|
|
* to be prepared undo if we fail to claim space.
|
|
*/
|
|
save_len = ei->i_da_metadata_calc_len;
|
|
save_last_lblock = ei->i_da_metadata_calc_last_lblock;
|
|
md_needed = EXT4_NUM_B2C(sbi,
|
|
ext4_calc_metadata_amount(inode, lblock));
|
|
trace_ext4_da_reserve_space(inode, md_needed);
|
|
|
|
/*
|
|
* We do still charge estimated metadata to the sb though;
|
|
* we cannot afford to run out of free blocks.
|
|
*/
|
|
if (ext4_claim_free_clusters(sbi, md_needed, 0)) {
|
|
ei->i_da_metadata_calc_len = save_len;
|
|
ei->i_da_metadata_calc_last_lblock = save_last_lblock;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
return -ENOSPC;
|
|
}
|
|
ei->i_reserved_meta_blocks += md_needed;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
|
|
return 0; /* success */
|
|
}
|
|
|
|
/*
|
|
* Reserve a single cluster located at lblock
|
|
*/
|
|
static int ext4_da_reserve_space(struct inode *inode, ext4_lblk_t lblock)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
unsigned int md_needed;
|
|
int ret;
|
|
ext4_lblk_t save_last_lblock;
|
|
int save_len;
|
|
|
|
/*
|
|
* We will charge metadata quota at writeout time; this saves
|
|
* us from metadata over-estimation, though we may go over by
|
|
* a small amount in the end. Here we just reserve for data.
|
|
*/
|
|
ret = dquot_reserve_block(inode, EXT4_C2B(sbi, 1));
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* recalculate the amount of metadata blocks to reserve
|
|
* in order to allocate nrblocks
|
|
* worse case is one extent per block
|
|
*/
|
|
spin_lock(&ei->i_block_reservation_lock);
|
|
/*
|
|
* ext4_calc_metadata_amount() has side effects, which we have
|
|
* to be prepared undo if we fail to claim space.
|
|
*/
|
|
save_len = ei->i_da_metadata_calc_len;
|
|
save_last_lblock = ei->i_da_metadata_calc_last_lblock;
|
|
md_needed = EXT4_NUM_B2C(sbi,
|
|
ext4_calc_metadata_amount(inode, lblock));
|
|
trace_ext4_da_reserve_space(inode, md_needed);
|
|
|
|
/*
|
|
* We do still charge estimated metadata to the sb though;
|
|
* we cannot afford to run out of free blocks.
|
|
*/
|
|
if (ext4_claim_free_clusters(sbi, md_needed + 1, 0)) {
|
|
ei->i_da_metadata_calc_len = save_len;
|
|
ei->i_da_metadata_calc_last_lblock = save_last_lblock;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
dquot_release_reservation_block(inode, EXT4_C2B(sbi, 1));
|
|
return -ENOSPC;
|
|
}
|
|
ei->i_reserved_data_blocks++;
|
|
ei->i_reserved_meta_blocks += md_needed;
|
|
spin_unlock(&ei->i_block_reservation_lock);
|
|
|
|
return 0; /* success */
|
|
}
|
|
|
|
static void ext4_da_release_space(struct inode *inode, int to_free)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
|
|
if (!to_free)
|
|
return; /* Nothing to release, exit */
|
|
|
|
spin_lock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
|
trace_ext4_da_release_space(inode, to_free);
|
|
if (unlikely(to_free > ei->i_reserved_data_blocks)) {
|
|
/*
|
|
* if there aren't enough reserved blocks, then the
|
|
* counter is messed up somewhere. Since this
|
|
* function is called from invalidate page, it's
|
|
* harmless to return without any action.
|
|
*/
|
|
ext4_warning(inode->i_sb, "ext4_da_release_space: "
|
|
"ino %lu, to_free %d with only %d reserved "
|
|
"data blocks", inode->i_ino, to_free,
|
|
ei->i_reserved_data_blocks);
|
|
WARN_ON(1);
|
|
to_free = ei->i_reserved_data_blocks;
|
|
}
|
|
ei->i_reserved_data_blocks -= to_free;
|
|
|
|
if (ei->i_reserved_data_blocks == 0) {
|
|
/*
|
|
* We can release all of the reserved metadata blocks
|
|
* only when we have written all of the delayed
|
|
* allocation blocks.
|
|
* Note that in case of bigalloc, i_reserved_meta_blocks,
|
|
* i_reserved_data_blocks, etc. refer to number of clusters.
|
|
*/
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter,
|
|
ei->i_reserved_meta_blocks);
|
|
ei->i_reserved_meta_blocks = 0;
|
|
ei->i_da_metadata_calc_len = 0;
|
|
}
|
|
|
|
/* update fs dirty data blocks counter */
|
|
percpu_counter_sub(&sbi->s_dirtyclusters_counter, to_free);
|
|
|
|
spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
|
|
|
|
dquot_release_reservation_block(inode, EXT4_C2B(sbi, to_free));
|
|
}
|
|
|
|
static void ext4_da_page_release_reservation(struct page *page,
|
|
unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
int to_release = 0;
|
|
struct buffer_head *head, *bh;
|
|
unsigned int curr_off = 0;
|
|
struct inode *inode = page->mapping->host;
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
unsigned int stop = offset + length;
|
|
int num_clusters;
|
|
ext4_fsblk_t lblk;
|
|
|
|
BUG_ON(stop > PAGE_CACHE_SIZE || stop < length);
|
|
|
|
head = page_buffers(page);
|
|
bh = head;
|
|
do {
|
|
unsigned int next_off = curr_off + bh->b_size;
|
|
|
|
if (next_off > stop)
|
|
break;
|
|
|
|
if ((offset <= curr_off) && (buffer_delay(bh))) {
|
|
to_release++;
|
|
clear_buffer_delay(bh);
|
|
}
|
|
curr_off = next_off;
|
|
} while ((bh = bh->b_this_page) != head);
|
|
|
|
if (to_release) {
|
|
lblk = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
ext4_es_remove_extent(inode, lblk, to_release);
|
|
}
|
|
|
|
/* If we have released all the blocks belonging to a cluster, then we
|
|
* need to release the reserved space for that cluster. */
|
|
num_clusters = EXT4_NUM_B2C(sbi, to_release);
|
|
while (num_clusters > 0) {
|
|
lblk = (page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits)) +
|
|
((num_clusters - 1) << sbi->s_cluster_bits);
|
|
if (sbi->s_cluster_ratio == 1 ||
|
|
!ext4_find_delalloc_cluster(inode, lblk))
|
|
ext4_da_release_space(inode, 1);
|
|
|
|
num_clusters--;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Delayed allocation stuff
|
|
*/
|
|
|
|
struct mpage_da_data {
|
|
struct inode *inode;
|
|
struct writeback_control *wbc;
|
|
|
|
pgoff_t first_page; /* The first page to write */
|
|
pgoff_t next_page; /* Current page to examine */
|
|
pgoff_t last_page; /* Last page to examine */
|
|
/*
|
|
* Extent to map - this can be after first_page because that can be
|
|
* fully mapped. We somewhat abuse m_flags to store whether the extent
|
|
* is delalloc or unwritten.
|
|
*/
|
|
struct ext4_map_blocks map;
|
|
struct ext4_io_submit io_submit; /* IO submission data */
|
|
};
|
|
|
|
static void mpage_release_unused_pages(struct mpage_da_data *mpd,
|
|
bool invalidate)
|
|
{
|
|
int nr_pages, i;
|
|
pgoff_t index, end;
|
|
struct pagevec pvec;
|
|
struct inode *inode = mpd->inode;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
|
|
/* This is necessary when next_page == 0. */
|
|
if (mpd->first_page >= mpd->next_page)
|
|
return;
|
|
|
|
index = mpd->first_page;
|
|
end = mpd->next_page - 1;
|
|
if (invalidate) {
|
|
ext4_lblk_t start, last;
|
|
start = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
last = end << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
ext4_es_remove_extent(inode, start, last - start + 1);
|
|
}
|
|
|
|
pagevec_init(&pvec, 0);
|
|
while (index <= end) {
|
|
nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
|
|
if (nr_pages == 0)
|
|
break;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
if (page->index > end)
|
|
break;
|
|
BUG_ON(!PageLocked(page));
|
|
BUG_ON(PageWriteback(page));
|
|
if (invalidate) {
|
|
block_invalidatepage(page, 0, PAGE_CACHE_SIZE);
|
|
ClearPageUptodate(page);
|
|
}
|
|
unlock_page(page);
|
|
}
|
|
index = pvec.pages[nr_pages - 1]->index + 1;
|
|
pagevec_release(&pvec);
|
|
}
|
|
}
|
|
|
|
static void ext4_print_free_blocks(struct inode *inode)
|
|
{
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
struct super_block *sb = inode->i_sb;
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
|
|
ext4_msg(sb, KERN_CRIT, "Total free blocks count %lld",
|
|
EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
ext4_count_free_clusters(sb)));
|
|
ext4_msg(sb, KERN_CRIT, "Free/Dirty block details");
|
|
ext4_msg(sb, KERN_CRIT, "free_blocks=%lld",
|
|
(long long) EXT4_C2B(EXT4_SB(sb),
|
|
percpu_counter_sum(&sbi->s_freeclusters_counter)));
|
|
ext4_msg(sb, KERN_CRIT, "dirty_blocks=%lld",
|
|
(long long) EXT4_C2B(EXT4_SB(sb),
|
|
percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
|
|
ext4_msg(sb, KERN_CRIT, "Block reservation details");
|
|
ext4_msg(sb, KERN_CRIT, "i_reserved_data_blocks=%u",
|
|
ei->i_reserved_data_blocks);
|
|
ext4_msg(sb, KERN_CRIT, "i_reserved_meta_blocks=%u",
|
|
ei->i_reserved_meta_blocks);
|
|
ext4_msg(sb, KERN_CRIT, "i_allocated_meta_blocks=%u",
|
|
ei->i_allocated_meta_blocks);
|
|
return;
|
|
}
|
|
|
|
static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
return (buffer_delay(bh) || buffer_unwritten(bh)) && buffer_dirty(bh);
|
|
}
|
|
|
|
/*
|
|
* This function is grabs code from the very beginning of
|
|
* ext4_map_blocks, but assumes that the caller is from delayed write
|
|
* time. This function looks up the requested blocks and sets the
|
|
* buffer delay bit under the protection of i_data_sem.
|
|
*/
|
|
static int ext4_da_map_blocks(struct inode *inode, sector_t iblock,
|
|
struct ext4_map_blocks *map,
|
|
struct buffer_head *bh)
|
|
{
|
|
struct extent_status es;
|
|
int retval;
|
|
sector_t invalid_block = ~((sector_t) 0xffff);
|
|
#ifdef ES_AGGRESSIVE_TEST
|
|
struct ext4_map_blocks orig_map;
|
|
|
|
memcpy(&orig_map, map, sizeof(*map));
|
|
#endif
|
|
|
|
if (invalid_block < ext4_blocks_count(EXT4_SB(inode->i_sb)->s_es))
|
|
invalid_block = ~0;
|
|
|
|
map->m_flags = 0;
|
|
ext_debug("ext4_da_map_blocks(): inode %lu, max_blocks %u,"
|
|
"logical block %lu\n", inode->i_ino, map->m_len,
|
|
(unsigned long) map->m_lblk);
|
|
|
|
/* Lookup extent status tree firstly */
|
|
if (ext4_es_lookup_extent(inode, iblock, &es)) {
|
|
ext4_es_lru_add(inode);
|
|
if (ext4_es_is_hole(&es)) {
|
|
retval = 0;
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
goto add_delayed;
|
|
}
|
|
|
|
/*
|
|
* Delayed extent could be allocated by fallocate.
|
|
* So we need to check it.
|
|
*/
|
|
if (ext4_es_is_delayed(&es) && !ext4_es_is_unwritten(&es)) {
|
|
map_bh(bh, inode->i_sb, invalid_block);
|
|
set_buffer_new(bh);
|
|
set_buffer_delay(bh);
|
|
return 0;
|
|
}
|
|
|
|
map->m_pblk = ext4_es_pblock(&es) + iblock - es.es_lblk;
|
|
retval = es.es_len - (iblock - es.es_lblk);
|
|
if (retval > map->m_len)
|
|
retval = map->m_len;
|
|
map->m_len = retval;
|
|
if (ext4_es_is_written(&es))
|
|
map->m_flags |= EXT4_MAP_MAPPED;
|
|
else if (ext4_es_is_unwritten(&es))
|
|
map->m_flags |= EXT4_MAP_UNWRITTEN;
|
|
else
|
|
BUG_ON(1);
|
|
|
|
#ifdef ES_AGGRESSIVE_TEST
|
|
ext4_map_blocks_es_recheck(NULL, inode, map, &orig_map, 0);
|
|
#endif
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* Try to see if we can get the block without requesting a new
|
|
* file system block.
|
|
*/
|
|
down_read((&EXT4_I(inode)->i_data_sem));
|
|
if (ext4_has_inline_data(inode)) {
|
|
/*
|
|
* We will soon create blocks for this page, and let
|
|
* us pretend as if the blocks aren't allocated yet.
|
|
* In case of clusters, we have to handle the work
|
|
* of mapping from cluster so that the reserved space
|
|
* is calculated properly.
|
|
*/
|
|
if ((EXT4_SB(inode->i_sb)->s_cluster_ratio > 1) &&
|
|
ext4_find_delalloc_cluster(inode, map->m_lblk))
|
|
map->m_flags |= EXT4_MAP_FROM_CLUSTER;
|
|
retval = 0;
|
|
} else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
retval = ext4_ext_map_blocks(NULL, inode, map,
|
|
EXT4_GET_BLOCKS_NO_PUT_HOLE);
|
|
else
|
|
retval = ext4_ind_map_blocks(NULL, inode, map,
|
|
EXT4_GET_BLOCKS_NO_PUT_HOLE);
|
|
|
|
add_delayed:
|
|
if (retval == 0) {
|
|
int ret;
|
|
/*
|
|
* XXX: __block_prepare_write() unmaps passed block,
|
|
* is it OK?
|
|
*/
|
|
/*
|
|
* If the block was allocated from previously allocated cluster,
|
|
* then we don't need to reserve it again. However we still need
|
|
* to reserve metadata for every block we're going to write.
|
|
*/
|
|
if (!(map->m_flags & EXT4_MAP_FROM_CLUSTER)) {
|
|
ret = ext4_da_reserve_space(inode, iblock);
|
|
if (ret) {
|
|
/* not enough space to reserve */
|
|
retval = ret;
|
|
goto out_unlock;
|
|
}
|
|
} else {
|
|
ret = ext4_da_reserve_metadata(inode, iblock);
|
|
if (ret) {
|
|
/* not enough space to reserve */
|
|
retval = ret;
|
|
goto out_unlock;
|
|
}
|
|
}
|
|
|
|
ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
|
|
~0, EXTENT_STATUS_DELAYED);
|
|
if (ret) {
|
|
retval = ret;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* Clear EXT4_MAP_FROM_CLUSTER flag since its purpose is served
|
|
* and it should not appear on the bh->b_state.
|
|
*/
|
|
map->m_flags &= ~EXT4_MAP_FROM_CLUSTER;
|
|
|
|
map_bh(bh, inode->i_sb, invalid_block);
|
|
set_buffer_new(bh);
|
|
set_buffer_delay(bh);
|
|
} else if (retval > 0) {
|
|
int ret;
|
|
unsigned int status;
|
|
|
|
if (unlikely(retval != map->m_len)) {
|
|
ext4_warning(inode->i_sb,
|
|
"ES len assertion failed for inode "
|
|
"%lu: retval %d != map->m_len %d",
|
|
inode->i_ino, retval, map->m_len);
|
|
WARN_ON(1);
|
|
}
|
|
|
|
status = map->m_flags & EXT4_MAP_UNWRITTEN ?
|
|
EXTENT_STATUS_UNWRITTEN : EXTENT_STATUS_WRITTEN;
|
|
ret = ext4_es_insert_extent(inode, map->m_lblk, map->m_len,
|
|
map->m_pblk, status);
|
|
if (ret != 0)
|
|
retval = ret;
|
|
}
|
|
|
|
out_unlock:
|
|
up_read((&EXT4_I(inode)->i_data_sem));
|
|
|
|
return retval;
|
|
}
|
|
|
|
/*
|
|
* This is a special get_blocks_t callback which is used by
|
|
* ext4_da_write_begin(). It will either return mapped block or
|
|
* reserve space for a single block.
|
|
*
|
|
* For delayed buffer_head we have BH_Mapped, BH_New, BH_Delay set.
|
|
* We also have b_blocknr = -1 and b_bdev initialized properly
|
|
*
|
|
* For unwritten buffer_head we have BH_Mapped, BH_New, BH_Unwritten set.
|
|
* We also have b_blocknr = physicalblock mapping unwritten extent and b_bdev
|
|
* initialized properly.
|
|
*/
|
|
int ext4_da_get_block_prep(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh, int create)
|
|
{
|
|
struct ext4_map_blocks map;
|
|
int ret = 0;
|
|
|
|
BUG_ON(create == 0);
|
|
BUG_ON(bh->b_size != inode->i_sb->s_blocksize);
|
|
|
|
map.m_lblk = iblock;
|
|
map.m_len = 1;
|
|
|
|
/*
|
|
* first, we need to know whether the block is allocated already
|
|
* preallocated blocks are unmapped but should treated
|
|
* the same as allocated blocks.
|
|
*/
|
|
ret = ext4_da_map_blocks(inode, iblock, &map, bh);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
map_bh(bh, inode->i_sb, map.m_pblk);
|
|
bh->b_state = (bh->b_state & ~EXT4_MAP_FLAGS) | map.m_flags;
|
|
|
|
if (buffer_unwritten(bh)) {
|
|
/* A delayed write to unwritten bh should be marked
|
|
* new and mapped. Mapped ensures that we don't do
|
|
* get_block multiple times when we write to the same
|
|
* offset and new ensures that we do proper zero out
|
|
* for partial write.
|
|
*/
|
|
set_buffer_new(bh);
|
|
set_buffer_mapped(bh);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int bget_one(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
get_bh(bh);
|
|
return 0;
|
|
}
|
|
|
|
static int bput_one(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
put_bh(bh);
|
|
return 0;
|
|
}
|
|
|
|
static int __ext4_journalled_writepage(struct page *page,
|
|
unsigned int len)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct inode *inode = mapping->host;
|
|
struct buffer_head *page_bufs = NULL;
|
|
handle_t *handle = NULL;
|
|
int ret = 0, err = 0;
|
|
int inline_data = ext4_has_inline_data(inode);
|
|
struct buffer_head *inode_bh = NULL;
|
|
|
|
ClearPageChecked(page);
|
|
|
|
if (inline_data) {
|
|
BUG_ON(page->index != 0);
|
|
BUG_ON(len > ext4_get_max_inline_size(inode));
|
|
inode_bh = ext4_journalled_write_inline_data(inode, len, page);
|
|
if (inode_bh == NULL)
|
|
goto out;
|
|
} else {
|
|
page_bufs = page_buffers(page);
|
|
if (!page_bufs) {
|
|
BUG();
|
|
goto out;
|
|
}
|
|
ext4_walk_page_buffers(handle, page_bufs, 0, len,
|
|
NULL, bget_one);
|
|
}
|
|
/* As soon as we unlock the page, it can go away, but we have
|
|
* references to buffers so we are safe */
|
|
unlock_page(page);
|
|
|
|
handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE,
|
|
ext4_writepage_trans_blocks(inode));
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
goto out;
|
|
}
|
|
|
|
BUG_ON(!ext4_handle_valid(handle));
|
|
|
|
if (inline_data) {
|
|
ret = ext4_journal_get_write_access(handle, inode_bh);
|
|
|
|
err = ext4_handle_dirty_metadata(handle, inode, inode_bh);
|
|
|
|
} else {
|
|
ret = ext4_walk_page_buffers(handle, page_bufs, 0, len, NULL,
|
|
do_journal_get_write_access);
|
|
|
|
err = ext4_walk_page_buffers(handle, page_bufs, 0, len, NULL,
|
|
write_end_fn);
|
|
}
|
|
if (ret == 0)
|
|
ret = err;
|
|
EXT4_I(inode)->i_datasync_tid = handle->h_transaction->t_tid;
|
|
err = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = err;
|
|
|
|
if (!ext4_has_inline_data(inode))
|
|
ext4_walk_page_buffers(NULL, page_bufs, 0, len,
|
|
NULL, bput_one);
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
out:
|
|
brelse(inode_bh);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Note that we don't need to start a transaction unless we're journaling data
|
|
* because we should have holes filled from ext4_page_mkwrite(). We even don't
|
|
* need to file the inode to the transaction's list in ordered mode because if
|
|
* we are writing back data added by write(), the inode is already there and if
|
|
* we are writing back data modified via mmap(), no one guarantees in which
|
|
* transaction the data will hit the disk. In case we are journaling data, we
|
|
* cannot start transaction directly because transaction start ranks above page
|
|
* lock so we have to do some magic.
|
|
*
|
|
* This function can get called via...
|
|
* - ext4_writepages after taking page lock (have journal handle)
|
|
* - journal_submit_inode_data_buffers (no journal handle)
|
|
* - shrink_page_list via the kswapd/direct reclaim (no journal handle)
|
|
* - grab_page_cache when doing write_begin (have journal handle)
|
|
*
|
|
* We don't do any block allocation in this function. If we have page with
|
|
* multiple blocks we need to write those buffer_heads that are mapped. This
|
|
* is important for mmaped based write. So if we do with blocksize 1K
|
|
* truncate(f, 1024);
|
|
* a = mmap(f, 0, 4096);
|
|
* a[0] = 'a';
|
|
* truncate(f, 4096);
|
|
* we have in the page first buffer_head mapped via page_mkwrite call back
|
|
* but other buffer_heads would be unmapped but dirty (dirty done via the
|
|
* do_wp_page). So writepage should write the first block. If we modify
|
|
* the mmap area beyond 1024 we will again get a page_fault and the
|
|
* page_mkwrite callback will do the block allocation and mark the
|
|
* buffer_heads mapped.
|
|
*
|
|
* We redirty the page if we have any buffer_heads that is either delay or
|
|
* unwritten in the page.
|
|
*
|
|
* We can get recursively called as show below.
|
|
*
|
|
* ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
|
|
* ext4_writepage()
|
|
*
|
|
* But since we don't do any block allocation we should not deadlock.
|
|
* Page also have the dirty flag cleared so we don't get recurive page_lock.
|
|
*/
|
|
static int ext4_writepage(struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
int ret = 0;
|
|
loff_t size;
|
|
unsigned int len;
|
|
struct buffer_head *page_bufs = NULL;
|
|
struct inode *inode = page->mapping->host;
|
|
struct ext4_io_submit io_submit;
|
|
|
|
trace_ext4_writepage(page);
|
|
size = i_size_read(inode);
|
|
if (page->index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
|
|
page_bufs = page_buffers(page);
|
|
/*
|
|
* We cannot do block allocation or other extent handling in this
|
|
* function. If there are buffers needing that, we have to redirty
|
|
* the page. But we may reach here when we do a journal commit via
|
|
* journal_submit_inode_data_buffers() and in that case we must write
|
|
* allocated buffers to achieve data=ordered mode guarantees.
|
|
*/
|
|
if (ext4_walk_page_buffers(NULL, page_bufs, 0, len, NULL,
|
|
ext4_bh_delay_or_unwritten)) {
|
|
redirty_page_for_writepage(wbc, page);
|
|
if (current->flags & PF_MEMALLOC) {
|
|
/*
|
|
* For memory cleaning there's no point in writing only
|
|
* some buffers. So just bail out. Warn if we came here
|
|
* from direct reclaim.
|
|
*/
|
|
WARN_ON_ONCE((current->flags & (PF_MEMALLOC|PF_KSWAPD))
|
|
== PF_MEMALLOC);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if (PageChecked(page) && ext4_should_journal_data(inode))
|
|
/*
|
|
* It's mmapped pagecache. Add buffers and journal it. There
|
|
* doesn't seem much point in redirtying the page here.
|
|
*/
|
|
return __ext4_journalled_writepage(page, len);
|
|
|
|
ext4_io_submit_init(&io_submit, wbc);
|
|
io_submit.io_end = ext4_init_io_end(inode, GFP_NOFS);
|
|
if (!io_submit.io_end) {
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return -ENOMEM;
|
|
}
|
|
ret = ext4_bio_write_page(&io_submit, page, len, wbc);
|
|
ext4_io_submit(&io_submit);
|
|
/* Drop io_end reference we got from init */
|
|
ext4_put_io_end_defer(io_submit.io_end);
|
|
return ret;
|
|
}
|
|
|
|
static int mpage_submit_page(struct mpage_da_data *mpd, struct page *page)
|
|
{
|
|
int len;
|
|
loff_t size = i_size_read(mpd->inode);
|
|
int err;
|
|
|
|
BUG_ON(page->index != mpd->first_page);
|
|
if (page->index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
clear_page_dirty_for_io(page);
|
|
err = ext4_bio_write_page(&mpd->io_submit, page, len, mpd->wbc);
|
|
if (!err)
|
|
mpd->wbc->nr_to_write--;
|
|
mpd->first_page++;
|
|
|
|
return err;
|
|
}
|
|
|
|
#define BH_FLAGS ((1 << BH_Unwritten) | (1 << BH_Delay))
|
|
|
|
/*
|
|
* mballoc gives us at most this number of blocks...
|
|
* XXX: That seems to be only a limitation of ext4_mb_normalize_request().
|
|
* The rest of mballoc seems to handle chunks up to full group size.
|
|
*/
|
|
#define MAX_WRITEPAGES_EXTENT_LEN 2048
|
|
|
|
/*
|
|
* mpage_add_bh_to_extent - try to add bh to extent of blocks to map
|
|
*
|
|
* @mpd - extent of blocks
|
|
* @lblk - logical number of the block in the file
|
|
* @bh - buffer head we want to add to the extent
|
|
*
|
|
* The function is used to collect contig. blocks in the same state. If the
|
|
* buffer doesn't require mapping for writeback and we haven't started the
|
|
* extent of buffers to map yet, the function returns 'true' immediately - the
|
|
* caller can write the buffer right away. Otherwise the function returns true
|
|
* if the block has been added to the extent, false if the block couldn't be
|
|
* added.
|
|
*/
|
|
static bool mpage_add_bh_to_extent(struct mpage_da_data *mpd, ext4_lblk_t lblk,
|
|
struct buffer_head *bh)
|
|
{
|
|
struct ext4_map_blocks *map = &mpd->map;
|
|
|
|
/* Buffer that doesn't need mapping for writeback? */
|
|
if (!buffer_dirty(bh) || !buffer_mapped(bh) ||
|
|
(!buffer_delay(bh) && !buffer_unwritten(bh))) {
|
|
/* So far no extent to map => we write the buffer right away */
|
|
if (map->m_len == 0)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/* First block in the extent? */
|
|
if (map->m_len == 0) {
|
|
map->m_lblk = lblk;
|
|
map->m_len = 1;
|
|
map->m_flags = bh->b_state & BH_FLAGS;
|
|
return true;
|
|
}
|
|
|
|
/* Don't go larger than mballoc is willing to allocate */
|
|
if (map->m_len >= MAX_WRITEPAGES_EXTENT_LEN)
|
|
return false;
|
|
|
|
/* Can we merge the block to our big extent? */
|
|
if (lblk == map->m_lblk + map->m_len &&
|
|
(bh->b_state & BH_FLAGS) == map->m_flags) {
|
|
map->m_len++;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* mpage_process_page_bufs - submit page buffers for IO or add them to extent
|
|
*
|
|
* @mpd - extent of blocks for mapping
|
|
* @head - the first buffer in the page
|
|
* @bh - buffer we should start processing from
|
|
* @lblk - logical number of the block in the file corresponding to @bh
|
|
*
|
|
* Walk through page buffers from @bh upto @head (exclusive) and either submit
|
|
* the page for IO if all buffers in this page were mapped and there's no
|
|
* accumulated extent of buffers to map or add buffers in the page to the
|
|
* extent of buffers to map. The function returns 1 if the caller can continue
|
|
* by processing the next page, 0 if it should stop adding buffers to the
|
|
* extent to map because we cannot extend it anymore. It can also return value
|
|
* < 0 in case of error during IO submission.
|
|
*/
|
|
static int mpage_process_page_bufs(struct mpage_da_data *mpd,
|
|
struct buffer_head *head,
|
|
struct buffer_head *bh,
|
|
ext4_lblk_t lblk)
|
|
{
|
|
struct inode *inode = mpd->inode;
|
|
int err;
|
|
ext4_lblk_t blocks = (i_size_read(inode) + (1 << inode->i_blkbits) - 1)
|
|
>> inode->i_blkbits;
|
|
|
|
do {
|
|
BUG_ON(buffer_locked(bh));
|
|
|
|
if (lblk >= blocks || !mpage_add_bh_to_extent(mpd, lblk, bh)) {
|
|
/* Found extent to map? */
|
|
if (mpd->map.m_len)
|
|
return 0;
|
|
/* Everything mapped so far and we hit EOF */
|
|
break;
|
|
}
|
|
} while (lblk++, (bh = bh->b_this_page) != head);
|
|
/* So far everything mapped? Submit the page for IO. */
|
|
if (mpd->map.m_len == 0) {
|
|
err = mpage_submit_page(mpd, head->b_page);
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
return lblk < blocks;
|
|
}
|
|
|
|
/*
|
|
* mpage_map_buffers - update buffers corresponding to changed extent and
|
|
* submit fully mapped pages for IO
|
|
*
|
|
* @mpd - description of extent to map, on return next extent to map
|
|
*
|
|
* Scan buffers corresponding to changed extent (we expect corresponding pages
|
|
* to be already locked) and update buffer state according to new extent state.
|
|
* We map delalloc buffers to their physical location, clear unwritten bits,
|
|
* and mark buffers as uninit when we perform writes to uninitialized extents
|
|
* and do extent conversion after IO is finished. If the last page is not fully
|
|
* mapped, we update @map to the next extent in the last page that needs
|
|
* mapping. Otherwise we submit the page for IO.
|
|
*/
|
|
static int mpage_map_and_submit_buffers(struct mpage_da_data *mpd)
|
|
{
|
|
struct pagevec pvec;
|
|
int nr_pages, i;
|
|
struct inode *inode = mpd->inode;
|
|
struct buffer_head *head, *bh;
|
|
int bpp_bits = PAGE_CACHE_SHIFT - inode->i_blkbits;
|
|
pgoff_t start, end;
|
|
ext4_lblk_t lblk;
|
|
sector_t pblock;
|
|
int err;
|
|
|
|
start = mpd->map.m_lblk >> bpp_bits;
|
|
end = (mpd->map.m_lblk + mpd->map.m_len - 1) >> bpp_bits;
|
|
lblk = start << bpp_bits;
|
|
pblock = mpd->map.m_pblk;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
while (start <= end) {
|
|
nr_pages = pagevec_lookup(&pvec, inode->i_mapping, start,
|
|
PAGEVEC_SIZE);
|
|
if (nr_pages == 0)
|
|
break;
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
|
|
if (page->index > end)
|
|
break;
|
|
/* Up to 'end' pages must be contiguous */
|
|
BUG_ON(page->index != start);
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (lblk < mpd->map.m_lblk)
|
|
continue;
|
|
if (lblk >= mpd->map.m_lblk + mpd->map.m_len) {
|
|
/*
|
|
* Buffer after end of mapped extent.
|
|
* Find next buffer in the page to map.
|
|
*/
|
|
mpd->map.m_len = 0;
|
|
mpd->map.m_flags = 0;
|
|
/*
|
|
* FIXME: If dioread_nolock supports
|
|
* blocksize < pagesize, we need to make
|
|
* sure we add size mapped so far to
|
|
* io_end->size as the following call
|
|
* can submit the page for IO.
|
|
*/
|
|
err = mpage_process_page_bufs(mpd, head,
|
|
bh, lblk);
|
|
pagevec_release(&pvec);
|
|
if (err > 0)
|
|
err = 0;
|
|
return err;
|
|
}
|
|
if (buffer_delay(bh)) {
|
|
clear_buffer_delay(bh);
|
|
bh->b_blocknr = pblock++;
|
|
}
|
|
clear_buffer_unwritten(bh);
|
|
} while (lblk++, (bh = bh->b_this_page) != head);
|
|
|
|
/*
|
|
* FIXME: This is going to break if dioread_nolock
|
|
* supports blocksize < pagesize as we will try to
|
|
* convert potentially unmapped parts of inode.
|
|
*/
|
|
mpd->io_submit.io_end->size += PAGE_CACHE_SIZE;
|
|
/* Page fully mapped - let IO run! */
|
|
err = mpage_submit_page(mpd, page);
|
|
if (err < 0) {
|
|
pagevec_release(&pvec);
|
|
return err;
|
|
}
|
|
start++;
|
|
}
|
|
pagevec_release(&pvec);
|
|
}
|
|
/* Extent fully mapped and matches with page boundary. We are done. */
|
|
mpd->map.m_len = 0;
|
|
mpd->map.m_flags = 0;
|
|
return 0;
|
|
}
|
|
|
|
static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
|
|
{
|
|
struct inode *inode = mpd->inode;
|
|
struct ext4_map_blocks *map = &mpd->map;
|
|
int get_blocks_flags;
|
|
int err;
|
|
|
|
trace_ext4_da_write_pages_extent(inode, map);
|
|
/*
|
|
* Call ext4_map_blocks() to allocate any delayed allocation blocks, or
|
|
* to convert an uninitialized extent to be initialized (in the case
|
|
* where we have written into one or more preallocated blocks). It is
|
|
* possible that we're going to need more metadata blocks than
|
|
* previously reserved. However we must not fail because we're in
|
|
* writeback and there is nothing we can do about it so it might result
|
|
* in data loss. So use reserved blocks to allocate metadata if
|
|
* possible.
|
|
*
|
|
* We pass in the magic EXT4_GET_BLOCKS_DELALLOC_RESERVE if the blocks
|
|
* in question are delalloc blocks. This affects functions in many
|
|
* different parts of the allocation call path. This flag exists
|
|
* primarily because we don't want to change *many* call functions, so
|
|
* ext4_map_blocks() will set the EXT4_STATE_DELALLOC_RESERVED flag
|
|
* once the inode's allocation semaphore is taken.
|
|
*/
|
|
get_blocks_flags = EXT4_GET_BLOCKS_CREATE |
|
|
EXT4_GET_BLOCKS_METADATA_NOFAIL;
|
|
if (ext4_should_dioread_nolock(inode))
|
|
get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
|
|
if (map->m_flags & (1 << BH_Delay))
|
|
get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
|
|
|
|
err = ext4_map_blocks(handle, inode, map, get_blocks_flags);
|
|
if (err < 0)
|
|
return err;
|
|
if (map->m_flags & EXT4_MAP_UNINIT) {
|
|
if (!mpd->io_submit.io_end->handle &&
|
|
ext4_handle_valid(handle)) {
|
|
mpd->io_submit.io_end->handle = handle->h_rsv_handle;
|
|
handle->h_rsv_handle = NULL;
|
|
}
|
|
ext4_set_io_unwritten_flag(inode, mpd->io_submit.io_end);
|
|
}
|
|
|
|
BUG_ON(map->m_len == 0);
|
|
if (map->m_flags & EXT4_MAP_NEW) {
|
|
struct block_device *bdev = inode->i_sb->s_bdev;
|
|
int i;
|
|
|
|
for (i = 0; i < map->m_len; i++)
|
|
unmap_underlying_metadata(bdev, map->m_pblk + i);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* mpage_map_and_submit_extent - map extent starting at mpd->lblk of length
|
|
* mpd->len and submit pages underlying it for IO
|
|
*
|
|
* @handle - handle for journal operations
|
|
* @mpd - extent to map
|
|
* @give_up_on_write - we set this to true iff there is a fatal error and there
|
|
* is no hope of writing the data. The caller should discard
|
|
* dirty pages to avoid infinite loops.
|
|
*
|
|
* The function maps extent starting at mpd->lblk of length mpd->len. If it is
|
|
* delayed, blocks are allocated, if it is unwritten, we may need to convert
|
|
* them to initialized or split the described range from larger unwritten
|
|
* extent. Note that we need not map all the described range since allocation
|
|
* can return less blocks or the range is covered by more unwritten extents. We
|
|
* cannot map more because we are limited by reserved transaction credits. On
|
|
* the other hand we always make sure that the last touched page is fully
|
|
* mapped so that it can be written out (and thus forward progress is
|
|
* guaranteed). After mapping we submit all mapped pages for IO.
|
|
*/
|
|
static int mpage_map_and_submit_extent(handle_t *handle,
|
|
struct mpage_da_data *mpd,
|
|
bool *give_up_on_write)
|
|
{
|
|
struct inode *inode = mpd->inode;
|
|
struct ext4_map_blocks *map = &mpd->map;
|
|
int err;
|
|
loff_t disksize;
|
|
|
|
mpd->io_submit.io_end->offset =
|
|
((loff_t)map->m_lblk) << inode->i_blkbits;
|
|
do {
|
|
err = mpage_map_one_extent(handle, mpd);
|
|
if (err < 0) {
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
if (EXT4_SB(sb)->s_mount_flags & EXT4_MF_FS_ABORTED)
|
|
goto invalidate_dirty_pages;
|
|
/*
|
|
* Let the uper layers retry transient errors.
|
|
* In the case of ENOSPC, if ext4_count_free_blocks()
|
|
* is non-zero, a commit should free up blocks.
|
|
*/
|
|
if ((err == -ENOMEM) ||
|
|
(err == -ENOSPC && ext4_count_free_clusters(sb)))
|
|
return err;
|
|
ext4_msg(sb, KERN_CRIT,
|
|
"Delayed block allocation failed for "
|
|
"inode %lu at logical offset %llu with"
|
|
" max blocks %u with error %d",
|
|
inode->i_ino,
|
|
(unsigned long long)map->m_lblk,
|
|
(unsigned)map->m_len, -err);
|
|
ext4_msg(sb, KERN_CRIT,
|
|
"This should not happen!! Data will "
|
|
"be lost\n");
|
|
if (err == -ENOSPC)
|
|
ext4_print_free_blocks(inode);
|
|
invalidate_dirty_pages:
|
|
*give_up_on_write = true;
|
|
return err;
|
|
}
|
|
/*
|
|
* Update buffer state, submit mapped pages, and get us new
|
|
* extent to map
|
|
*/
|
|
err = mpage_map_and_submit_buffers(mpd);
|
|
if (err < 0)
|
|
return err;
|
|
} while (map->m_len);
|
|
|
|
/* Update on-disk size after IO is submitted */
|
|
disksize = ((loff_t)mpd->first_page) << PAGE_CACHE_SHIFT;
|
|
if (disksize > EXT4_I(inode)->i_disksize) {
|
|
int err2;
|
|
|
|
ext4_wb_update_i_disksize(inode, disksize);
|
|
err2 = ext4_mark_inode_dirty(handle, inode);
|
|
if (err2)
|
|
ext4_error(inode->i_sb,
|
|
"Failed to mark inode %lu dirty",
|
|
inode->i_ino);
|
|
if (!err)
|
|
err = err2;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Calculate the total number of credits to reserve for one writepages
|
|
* iteration. This is called from ext4_writepages(). We map an extent of
|
|
* up to MAX_WRITEPAGES_EXTENT_LEN blocks and then we go on and finish mapping
|
|
* the last partial page. So in total we can map MAX_WRITEPAGES_EXTENT_LEN +
|
|
* bpp - 1 blocks in bpp different extents.
|
|
*/
|
|
static int ext4_da_writepages_trans_blocks(struct inode *inode)
|
|
{
|
|
int bpp = ext4_journal_blocks_per_page(inode);
|
|
|
|
return ext4_meta_trans_blocks(inode,
|
|
MAX_WRITEPAGES_EXTENT_LEN + bpp - 1, bpp);
|
|
}
|
|
|
|
/*
|
|
* mpage_prepare_extent_to_map - find & lock contiguous range of dirty pages
|
|
* and underlying extent to map
|
|
*
|
|
* @mpd - where to look for pages
|
|
*
|
|
* Walk dirty pages in the mapping. If they are fully mapped, submit them for
|
|
* IO immediately. When we find a page which isn't mapped we start accumulating
|
|
* extent of buffers underlying these pages that needs mapping (formed by
|
|
* either delayed or unwritten buffers). We also lock the pages containing
|
|
* these buffers. The extent found is returned in @mpd structure (starting at
|
|
* mpd->lblk with length mpd->len blocks).
|
|
*
|
|
* Note that this function can attach bios to one io_end structure which are
|
|
* neither logically nor physically contiguous. Although it may seem as an
|
|
* unnecessary complication, it is actually inevitable in blocksize < pagesize
|
|
* case as we need to track IO to all buffers underlying a page in one io_end.
|
|
*/
|
|
static int mpage_prepare_extent_to_map(struct mpage_da_data *mpd)
|
|
{
|
|
struct address_space *mapping = mpd->inode->i_mapping;
|
|
struct pagevec pvec;
|
|
unsigned int nr_pages;
|
|
long left = mpd->wbc->nr_to_write;
|
|
pgoff_t index = mpd->first_page;
|
|
pgoff_t end = mpd->last_page;
|
|
int tag;
|
|
int i, err = 0;
|
|
int blkbits = mpd->inode->i_blkbits;
|
|
ext4_lblk_t lblk;
|
|
struct buffer_head *head;
|
|
|
|
if (mpd->wbc->sync_mode == WB_SYNC_ALL || mpd->wbc->tagged_writepages)
|
|
tag = PAGECACHE_TAG_TOWRITE;
|
|
else
|
|
tag = PAGECACHE_TAG_DIRTY;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
mpd->map.m_len = 0;
|
|
mpd->next_page = index;
|
|
while (index <= end) {
|
|
nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
|
|
min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
|
|
if (nr_pages == 0)
|
|
goto out;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec.pages[i];
|
|
|
|
/*
|
|
* At this point, the page may be truncated or
|
|
* invalidated (changing page->mapping to NULL), or
|
|
* even swizzled back from swapper_space to tmpfs file
|
|
* mapping. However, page->index will not change
|
|
* because we have a reference on the page.
|
|
*/
|
|
if (page->index > end)
|
|
goto out;
|
|
|
|
/*
|
|
* Accumulated enough dirty pages? This doesn't apply
|
|
* to WB_SYNC_ALL mode. For integrity sync we have to
|
|
* keep going because someone may be concurrently
|
|
* dirtying pages, and we might have synced a lot of
|
|
* newly appeared dirty pages, but have not synced all
|
|
* of the old dirty pages.
|
|
*/
|
|
if (mpd->wbc->sync_mode == WB_SYNC_NONE && left <= 0)
|
|
goto out;
|
|
|
|
/* If we can't merge this page, we are done. */
|
|
if (mpd->map.m_len > 0 && mpd->next_page != page->index)
|
|
goto out;
|
|
|
|
lock_page(page);
|
|
/*
|
|
* If the page is no longer dirty, or its mapping no
|
|
* longer corresponds to inode we are writing (which
|
|
* means it has been truncated or invalidated), or the
|
|
* page is already under writeback and we are not doing
|
|
* a data integrity writeback, skip the page
|
|
*/
|
|
if (!PageDirty(page) ||
|
|
(PageWriteback(page) &&
|
|
(mpd->wbc->sync_mode == WB_SYNC_NONE)) ||
|
|
unlikely(page->mapping != mapping)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
wait_on_page_writeback(page);
|
|
BUG_ON(PageWriteback(page));
|
|
|
|
if (mpd->map.m_len == 0)
|
|
mpd->first_page = page->index;
|
|
mpd->next_page = page->index + 1;
|
|
/* Add all dirty buffers to mpd */
|
|
lblk = ((ext4_lblk_t)page->index) <<
|
|
(PAGE_CACHE_SHIFT - blkbits);
|
|
head = page_buffers(page);
|
|
err = mpage_process_page_bufs(mpd, head, head, lblk);
|
|
if (err <= 0)
|
|
goto out;
|
|
err = 0;
|
|
left--;
|
|
}
|
|
pagevec_release(&pvec);
|
|
cond_resched();
|
|
}
|
|
return 0;
|
|
out:
|
|
pagevec_release(&pvec);
|
|
return err;
|
|
}
|
|
|
|
static int __writepage(struct page *page, struct writeback_control *wbc,
|
|
void *data)
|
|
{
|
|
struct address_space *mapping = data;
|
|
int ret = ext4_writepage(page, wbc);
|
|
mapping_set_error(mapping, ret);
|
|
return ret;
|
|
}
|
|
|
|
static int ext4_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
pgoff_t writeback_index = 0;
|
|
long nr_to_write = wbc->nr_to_write;
|
|
int range_whole = 0;
|
|
int cycled = 1;
|
|
handle_t *handle = NULL;
|
|
struct mpage_da_data mpd;
|
|
struct inode *inode = mapping->host;
|
|
int needed_blocks, rsv_blocks = 0, ret = 0;
|
|
struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
|
|
bool done;
|
|
struct blk_plug plug;
|
|
bool give_up_on_write = false;
|
|
|
|
trace_ext4_writepages(inode, wbc);
|
|
|
|
/*
|
|
* No pages to write? This is mainly a kludge to avoid starting
|
|
* a transaction for special inodes like journal inode on last iput()
|
|
* because that could violate lock ordering on umount
|
|
*/
|
|
if (!mapping->nrpages || !mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
|
|
goto out_writepages;
|
|
|
|
if (ext4_should_journal_data(inode)) {
|
|
struct blk_plug plug;
|
|
|
|
blk_start_plug(&plug);
|
|
ret = write_cache_pages(mapping, wbc, __writepage, mapping);
|
|
blk_finish_plug(&plug);
|
|
goto out_writepages;
|
|
}
|
|
|
|
/*
|
|
* If the filesystem has aborted, it is read-only, so return
|
|
* right away instead of dumping stack traces later on that
|
|
* will obscure the real source of the problem. We test
|
|
* EXT4_MF_FS_ABORTED instead of sb->s_flag's MS_RDONLY because
|
|
* the latter could be true if the filesystem is mounted
|
|
* read-only, and in that case, ext4_writepages should
|
|
* *never* be called, so if that ever happens, we would want
|
|
* the stack trace.
|
|
*/
|
|
if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED)) {
|
|
ret = -EROFS;
|
|
goto out_writepages;
|
|
}
|
|
|
|
if (ext4_should_dioread_nolock(inode)) {
|
|
/*
|
|
* We may need to convert up to one extent per block in
|
|
* the page and we may dirty the inode.
|
|
*/
|
|
rsv_blocks = 1 + (PAGE_CACHE_SIZE >> inode->i_blkbits);
|
|
}
|
|
|
|
/*
|
|
* If we have inline data and arrive here, it means that
|
|
* we will soon create the block for the 1st page, so
|
|
* we'd better clear the inline data here.
|
|
*/
|
|
if (ext4_has_inline_data(inode)) {
|
|
/* Just inode will be modified... */
|
|
handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
goto out_writepages;
|
|
}
|
|
BUG_ON(ext4_test_inode_state(inode,
|
|
EXT4_STATE_MAY_INLINE_DATA));
|
|
ext4_destroy_inline_data(handle, inode);
|
|
ext4_journal_stop(handle);
|
|
}
|
|
|
|
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
|
|
range_whole = 1;
|
|
|
|
if (wbc->range_cyclic) {
|
|
writeback_index = mapping->writeback_index;
|
|
if (writeback_index)
|
|
cycled = 0;
|
|
mpd.first_page = writeback_index;
|
|
mpd.last_page = -1;
|
|
} else {
|
|
mpd.first_page = wbc->range_start >> PAGE_CACHE_SHIFT;
|
|
mpd.last_page = wbc->range_end >> PAGE_CACHE_SHIFT;
|
|
}
|
|
|
|
mpd.inode = inode;
|
|
mpd.wbc = wbc;
|
|
ext4_io_submit_init(&mpd.io_submit, wbc);
|
|
retry:
|
|
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
|
|
tag_pages_for_writeback(mapping, mpd.first_page, mpd.last_page);
|
|
done = false;
|
|
blk_start_plug(&plug);
|
|
while (!done && mpd.first_page <= mpd.last_page) {
|
|
/* For each extent of pages we use new io_end */
|
|
mpd.io_submit.io_end = ext4_init_io_end(inode, GFP_KERNEL);
|
|
if (!mpd.io_submit.io_end) {
|
|
ret = -ENOMEM;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* We have two constraints: We find one extent to map and we
|
|
* must always write out whole page (makes a difference when
|
|
* blocksize < pagesize) so that we don't block on IO when we
|
|
* try to write out the rest of the page. Journalled mode is
|
|
* not supported by delalloc.
|
|
*/
|
|
BUG_ON(ext4_should_journal_data(inode));
|
|
needed_blocks = ext4_da_writepages_trans_blocks(inode);
|
|
|
|
/* start a new transaction */
|
|
handle = ext4_journal_start_with_reserve(inode,
|
|
EXT4_HT_WRITE_PAGE, needed_blocks, rsv_blocks);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
|
|
"%ld pages, ino %lu; err %d", __func__,
|
|
wbc->nr_to_write, inode->i_ino, ret);
|
|
/* Release allocated io_end */
|
|
ext4_put_io_end(mpd.io_submit.io_end);
|
|
break;
|
|
}
|
|
|
|
trace_ext4_da_write_pages(inode, mpd.first_page, mpd.wbc);
|
|
ret = mpage_prepare_extent_to_map(&mpd);
|
|
if (!ret) {
|
|
if (mpd.map.m_len)
|
|
ret = mpage_map_and_submit_extent(handle, &mpd,
|
|
&give_up_on_write);
|
|
else {
|
|
/*
|
|
* We scanned the whole range (or exhausted
|
|
* nr_to_write), submitted what was mapped and
|
|
* didn't find anything needing mapping. We are
|
|
* done.
|
|
*/
|
|
done = true;
|
|
}
|
|
}
|
|
ext4_journal_stop(handle);
|
|
/* Submit prepared bio */
|
|
ext4_io_submit(&mpd.io_submit);
|
|
/* Unlock pages we didn't use */
|
|
mpage_release_unused_pages(&mpd, give_up_on_write);
|
|
/* Drop our io_end reference we got from init */
|
|
ext4_put_io_end(mpd.io_submit.io_end);
|
|
|
|
if (ret == -ENOSPC && sbi->s_journal) {
|
|
/*
|
|
* Commit the transaction which would
|
|
* free blocks released in the transaction
|
|
* and try again
|
|
*/
|
|
jbd2_journal_force_commit_nested(sbi->s_journal);
|
|
ret = 0;
|
|
continue;
|
|
}
|
|
/* Fatal error - ENOMEM, EIO... */
|
|
if (ret)
|
|
break;
|
|
}
|
|
blk_finish_plug(&plug);
|
|
if (!ret && !cycled && wbc->nr_to_write > 0) {
|
|
cycled = 1;
|
|
mpd.last_page = writeback_index - 1;
|
|
mpd.first_page = 0;
|
|
goto retry;
|
|
}
|
|
|
|
/* Update index */
|
|
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
|
|
/*
|
|
* Set the writeback_index so that range_cyclic
|
|
* mode will write it back later
|
|
*/
|
|
mapping->writeback_index = mpd.first_page;
|
|
|
|
out_writepages:
|
|
trace_ext4_writepages_result(inode, wbc, ret,
|
|
nr_to_write - wbc->nr_to_write);
|
|
return ret;
|
|
}
|
|
|
|
static int ext4_nonda_switch(struct super_block *sb)
|
|
{
|
|
s64 free_clusters, dirty_clusters;
|
|
struct ext4_sb_info *sbi = EXT4_SB(sb);
|
|
|
|
/*
|
|
* switch to non delalloc mode if we are running low
|
|
* on free block. The free block accounting via percpu
|
|
* counters can get slightly wrong with percpu_counter_batch getting
|
|
* accumulated on each CPU without updating global counters
|
|
* Delalloc need an accurate free block accounting. So switch
|
|
* to non delalloc when we are near to error range.
|
|
*/
|
|
free_clusters =
|
|
percpu_counter_read_positive(&sbi->s_freeclusters_counter);
|
|
dirty_clusters =
|
|
percpu_counter_read_positive(&sbi->s_dirtyclusters_counter);
|
|
/*
|
|
* Start pushing delalloc when 1/2 of free blocks are dirty.
|
|
*/
|
|
if (dirty_clusters && (free_clusters < 2 * dirty_clusters))
|
|
try_to_writeback_inodes_sb(sb, WB_REASON_FS_FREE_SPACE);
|
|
|
|
if (2 * free_clusters < 3 * dirty_clusters ||
|
|
free_clusters < (dirty_clusters + EXT4_FREECLUSTERS_WATERMARK)) {
|
|
/*
|
|
* free block count is less than 150% of dirty blocks
|
|
* or free blocks is less than watermark
|
|
*/
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int ext4_da_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
int ret, retries = 0;
|
|
struct page *page;
|
|
pgoff_t index;
|
|
struct inode *inode = mapping->host;
|
|
handle_t *handle;
|
|
|
|
index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
if (ext4_nonda_switch(inode->i_sb)) {
|
|
*fsdata = (void *)FALL_BACK_TO_NONDELALLOC;
|
|
return ext4_write_begin(file, mapping, pos,
|
|
len, flags, pagep, fsdata);
|
|
}
|
|
*fsdata = (void *)0;
|
|
trace_ext4_da_write_begin(inode, pos, len, flags);
|
|
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) {
|
|
ret = ext4_da_write_inline_data_begin(mapping, inode,
|
|
pos, len, flags,
|
|
pagep, fsdata);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (ret == 1)
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* grab_cache_page_write_begin() can take a long time if the
|
|
* system is thrashing due to memory pressure, or if the page
|
|
* is being written back. So grab it first before we start
|
|
* the transaction handle. This also allows us to allocate
|
|
* the page (if needed) without using GFP_NOFS.
|
|
*/
|
|
retry_grab:
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
unlock_page(page);
|
|
|
|
/*
|
|
* With delayed allocation, we don't log the i_disksize update
|
|
* if there is delayed block allocation. But we still need
|
|
* to journalling the i_disksize update if writes to the end
|
|
* of file which has an already mapped buffer.
|
|
*/
|
|
retry_journal:
|
|
handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, 1);
|
|
if (IS_ERR(handle)) {
|
|
page_cache_release(page);
|
|
return PTR_ERR(handle);
|
|
}
|
|
|
|
lock_page(page);
|
|
if (page->mapping != mapping) {
|
|
/* The page got truncated from under us */
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
ext4_journal_stop(handle);
|
|
goto retry_grab;
|
|
}
|
|
/* In case writeback began while the page was unlocked */
|
|
wait_for_stable_page(page);
|
|
|
|
ret = __block_write_begin(page, pos, len, ext4_da_get_block_prep);
|
|
if (ret < 0) {
|
|
unlock_page(page);
|
|
ext4_journal_stop(handle);
|
|
/*
|
|
* block_write_begin may have instantiated a few blocks
|
|
* outside i_size. Trim these off again. Don't need
|
|
* i_size_read because we hold i_mutex.
|
|
*/
|
|
if (pos + len > inode->i_size)
|
|
ext4_truncate_failed_write(inode);
|
|
|
|
if (ret == -ENOSPC &&
|
|
ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry_journal;
|
|
|
|
page_cache_release(page);
|
|
return ret;
|
|
}
|
|
|
|
*pagep = page;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Check if we should update i_disksize
|
|
* when write to the end of file but not require block allocation
|
|
*/
|
|
static int ext4_da_should_update_i_disksize(struct page *page,
|
|
unsigned long offset)
|
|
{
|
|
struct buffer_head *bh;
|
|
struct inode *inode = page->mapping->host;
|
|
unsigned int idx;
|
|
int i;
|
|
|
|
bh = page_buffers(page);
|
|
idx = offset >> inode->i_blkbits;
|
|
|
|
for (i = 0; i < idx; i++)
|
|
bh = bh->b_this_page;
|
|
|
|
if (!buffer_mapped(bh) || (buffer_delay(bh)) || buffer_unwritten(bh))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int ext4_da_write_end(struct file *file,
|
|
struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
int ret = 0, ret2;
|
|
handle_t *handle = ext4_journal_current_handle();
|
|
loff_t new_i_size;
|
|
unsigned long start, end;
|
|
int write_mode = (int)(unsigned long)fsdata;
|
|
|
|
if (write_mode == FALL_BACK_TO_NONDELALLOC)
|
|
return ext4_write_end(file, mapping, pos,
|
|
len, copied, page, fsdata);
|
|
|
|
trace_ext4_da_write_end(inode, pos, len, copied);
|
|
start = pos & (PAGE_CACHE_SIZE - 1);
|
|
end = start + copied - 1;
|
|
|
|
/*
|
|
* generic_write_end() will run mark_inode_dirty() if i_size
|
|
* changes. So let's piggyback the i_disksize mark_inode_dirty
|
|
* into that.
|
|
*/
|
|
new_i_size = pos + copied;
|
|
if (copied && new_i_size > EXT4_I(inode)->i_disksize) {
|
|
if (ext4_has_inline_data(inode) ||
|
|
ext4_da_should_update_i_disksize(page, end)) {
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
if (new_i_size > EXT4_I(inode)->i_disksize)
|
|
EXT4_I(inode)->i_disksize = new_i_size;
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
/* We need to mark inode dirty even if
|
|
* new_i_size is less that inode->i_size
|
|
* bu greater than i_disksize.(hint delalloc)
|
|
*/
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
}
|
|
}
|
|
|
|
if (write_mode != CONVERT_INLINE_DATA &&
|
|
ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) &&
|
|
ext4_has_inline_data(inode))
|
|
ret2 = ext4_da_write_inline_data_end(inode, pos, len, copied,
|
|
page);
|
|
else
|
|
ret2 = generic_write_end(file, mapping, pos, len, copied,
|
|
page, fsdata);
|
|
|
|
copied = ret2;
|
|
if (ret2 < 0)
|
|
ret = ret2;
|
|
ret2 = ext4_journal_stop(handle);
|
|
if (!ret)
|
|
ret = ret2;
|
|
|
|
return ret ? ret : copied;
|
|
}
|
|
|
|
static void ext4_da_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
/*
|
|
* Drop reserved blocks
|
|
*/
|
|
BUG_ON(!PageLocked(page));
|
|
if (!page_has_buffers(page))
|
|
goto out;
|
|
|
|
ext4_da_page_release_reservation(page, offset, length);
|
|
|
|
out:
|
|
ext4_invalidatepage(page, offset, length);
|
|
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Force all delayed allocation blocks to be allocated for a given inode.
|
|
*/
|
|
int ext4_alloc_da_blocks(struct inode *inode)
|
|
{
|
|
trace_ext4_alloc_da_blocks(inode);
|
|
|
|
if (!EXT4_I(inode)->i_reserved_data_blocks &&
|
|
!EXT4_I(inode)->i_reserved_meta_blocks)
|
|
return 0;
|
|
|
|
/*
|
|
* We do something simple for now. The filemap_flush() will
|
|
* also start triggering a write of the data blocks, which is
|
|
* not strictly speaking necessary (and for users of
|
|
* laptop_mode, not even desirable). However, to do otherwise
|
|
* would require replicating code paths in:
|
|
*
|
|
* ext4_writepages() ->
|
|
* write_cache_pages() ---> (via passed in callback function)
|
|
* __mpage_da_writepage() -->
|
|
* mpage_add_bh_to_extent()
|
|
* mpage_da_map_blocks()
|
|
*
|
|
* The problem is that write_cache_pages(), located in
|
|
* mm/page-writeback.c, marks pages clean in preparation for
|
|
* doing I/O, which is not desirable if we're not planning on
|
|
* doing I/O at all.
|
|
*
|
|
* We could call write_cache_pages(), and then redirty all of
|
|
* the pages by calling redirty_page_for_writepage() but that
|
|
* would be ugly in the extreme. So instead we would need to
|
|
* replicate parts of the code in the above functions,
|
|
* simplifying them because we wouldn't actually intend to
|
|
* write out the pages, but rather only collect contiguous
|
|
* logical block extents, call the multi-block allocator, and
|
|
* then update the buffer heads with the block allocations.
|
|
*
|
|
* For now, though, we'll cheat by calling filemap_flush(),
|
|
* which will map the blocks, and start the I/O, but not
|
|
* actually wait for the I/O to complete.
|
|
*/
|
|
return filemap_flush(inode->i_mapping);
|
|
}
|
|
|
|
/*
|
|
* bmap() is special. It gets used by applications such as lilo and by
|
|
* the swapper to find the on-disk block of a specific piece of data.
|
|
*
|
|
* Naturally, this is dangerous if the block concerned is still in the
|
|
* journal. If somebody makes a swapfile on an ext4 data-journaling
|
|
* filesystem and enables swap, then they may get a nasty shock when the
|
|
* data getting swapped to that swapfile suddenly gets overwritten by
|
|
* the original zero's written out previously to the journal and
|
|
* awaiting writeback in the kernel's buffer cache.
|
|
*
|
|
* So, if we see any bmap calls here on a modified, data-journaled file,
|
|
* take extra steps to flush any blocks which might be in the cache.
|
|
*/
|
|
static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
journal_t *journal;
|
|
int err;
|
|
|
|
/*
|
|
* We can get here for an inline file via the FIBMAP ioctl
|
|
*/
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) &&
|
|
test_opt(inode->i_sb, DELALLOC)) {
|
|
/*
|
|
* With delalloc we want to sync the file
|
|
* so that we can make sure we allocate
|
|
* blocks for file
|
|
*/
|
|
filemap_write_and_wait(mapping);
|
|
}
|
|
|
|
if (EXT4_JOURNAL(inode) &&
|
|
ext4_test_inode_state(inode, EXT4_STATE_JDATA)) {
|
|
/*
|
|
* This is a REALLY heavyweight approach, but the use of
|
|
* bmap on dirty files is expected to be extremely rare:
|
|
* only if we run lilo or swapon on a freshly made file
|
|
* do we expect this to happen.
|
|
*
|
|
* (bmap requires CAP_SYS_RAWIO so this does not
|
|
* represent an unprivileged user DOS attack --- we'd be
|
|
* in trouble if mortal users could trigger this path at
|
|
* will.)
|
|
*
|
|
* NB. EXT4_STATE_JDATA is not set on files other than
|
|
* regular files. If somebody wants to bmap a directory
|
|
* or symlink and gets confused because the buffer
|
|
* hasn't yet been flushed to disk, they deserve
|
|
* everything they get.
|
|
*/
|
|
|
|
ext4_clear_inode_state(inode, EXT4_STATE_JDATA);
|
|
journal = EXT4_JOURNAL(inode);
|
|
jbd2_journal_lock_updates(journal);
|
|
err = jbd2_journal_flush(journal);
|
|
jbd2_journal_unlock_updates(journal);
|
|
|
|
if (err)
|
|
return 0;
|
|
}
|
|
|
|
return generic_block_bmap(mapping, block, ext4_get_block);
|
|
}
|
|
|
|
static int ext4_readpage(struct file *file, struct page *page)
|
|
{
|
|
int ret = -EAGAIN;
|
|
struct inode *inode = page->mapping->host;
|
|
|
|
trace_ext4_readpage(page);
|
|
|
|
if (ext4_has_inline_data(inode))
|
|
ret = ext4_readpage_inline(inode, page);
|
|
|
|
if (ret == -EAGAIN)
|
|
return mpage_readpage(page, ext4_get_block);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
ext4_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
|
|
/* If the file has inline data, no need to do readpages. */
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
|
|
}
|
|
|
|
static void ext4_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
trace_ext4_invalidatepage(page, offset, length);
|
|
|
|
/* No journalling happens on data buffers when this function is used */
|
|
WARN_ON(page_has_buffers(page) && buffer_jbd(page_buffers(page)));
|
|
|
|
block_invalidatepage(page, offset, length);
|
|
}
|
|
|
|
static int __ext4_journalled_invalidatepage(struct page *page,
|
|
unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
journal_t *journal = EXT4_JOURNAL(page->mapping->host);
|
|
|
|
trace_ext4_journalled_invalidatepage(page, offset, length);
|
|
|
|
/*
|
|
* If it's a full truncate we just forget about the pending dirtying
|
|
*/
|
|
if (offset == 0 && length == PAGE_CACHE_SIZE)
|
|
ClearPageChecked(page);
|
|
|
|
return jbd2_journal_invalidatepage(journal, page, offset, length);
|
|
}
|
|
|
|
/* Wrapper for aops... */
|
|
static void ext4_journalled_invalidatepage(struct page *page,
|
|
unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
WARN_ON(__ext4_journalled_invalidatepage(page, offset, length) < 0);
|
|
}
|
|
|
|
static int ext4_releasepage(struct page *page, gfp_t wait)
|
|
{
|
|
journal_t *journal = EXT4_JOURNAL(page->mapping->host);
|
|
|
|
trace_ext4_releasepage(page);
|
|
|
|
/* Page has dirty journalled data -> cannot release */
|
|
if (PageChecked(page))
|
|
return 0;
|
|
if (journal)
|
|
return jbd2_journal_try_to_free_buffers(journal, page, wait);
|
|
else
|
|
return try_to_free_buffers(page);
|
|
}
|
|
|
|
/*
|
|
* ext4_get_block used when preparing for a DIO write or buffer write.
|
|
* We allocate an uinitialized extent if blocks haven't been allocated.
|
|
* The extent will be converted to initialized after the IO is complete.
|
|
*/
|
|
int ext4_get_block_write(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
ext4_debug("ext4_get_block_write: inode %lu, create flag %d\n",
|
|
inode->i_ino, create);
|
|
return _ext4_get_block(inode, iblock, bh_result,
|
|
EXT4_GET_BLOCKS_IO_CREATE_EXT);
|
|
}
|
|
|
|
static int ext4_get_block_write_nolock(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
ext4_debug("ext4_get_block_write_nolock: inode %lu, create flag %d\n",
|
|
inode->i_ino, create);
|
|
return _ext4_get_block(inode, iblock, bh_result,
|
|
EXT4_GET_BLOCKS_NO_LOCK);
|
|
}
|
|
|
|
static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
|
|
ssize_t size, void *private)
|
|
{
|
|
ext4_io_end_t *io_end = iocb->private;
|
|
|
|
/* if not async direct IO just return */
|
|
if (!io_end)
|
|
return;
|
|
|
|
ext_debug("ext4_end_io_dio(): io_end 0x%p "
|
|
"for inode %lu, iocb 0x%p, offset %llu, size %zd\n",
|
|
iocb->private, io_end->inode->i_ino, iocb, offset,
|
|
size);
|
|
|
|
iocb->private = NULL;
|
|
io_end->offset = offset;
|
|
io_end->size = size;
|
|
ext4_put_io_end(io_end);
|
|
}
|
|
|
|
/*
|
|
* For ext4 extent files, ext4 will do direct-io write to holes,
|
|
* preallocated extents, and those write extend the file, no need to
|
|
* fall back to buffered IO.
|
|
*
|
|
* For holes, we fallocate those blocks, mark them as uninitialized
|
|
* If those blocks were preallocated, we mark sure they are split, but
|
|
* still keep the range to write as uninitialized.
|
|
*
|
|
* The unwritten extents will be converted to written when DIO is completed.
|
|
* For async direct IO, since the IO may still pending when return, we
|
|
* set up an end_io call back function, which will do the conversion
|
|
* when async direct IO completed.
|
|
*
|
|
* If the O_DIRECT write will extend the file then add this inode to the
|
|
* orphan list. So recovery will truncate it back to the original size
|
|
* if the machine crashes during the write.
|
|
*
|
|
*/
|
|
static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
ssize_t ret;
|
|
size_t count = iov_length(iov, nr_segs);
|
|
int overwrite = 0;
|
|
get_block_t *get_block_func = NULL;
|
|
int dio_flags = 0;
|
|
loff_t final_size = offset + count;
|
|
ext4_io_end_t *io_end = NULL;
|
|
|
|
/* Use the old path for reads and writes beyond i_size. */
|
|
if (rw != WRITE || final_size > inode->i_size)
|
|
return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
|
|
BUG_ON(iocb->private == NULL);
|
|
|
|
/*
|
|
* Make all waiters for direct IO properly wait also for extent
|
|
* conversion. This also disallows race between truncate() and
|
|
* overwrite DIO as i_dio_count needs to be incremented under i_mutex.
|
|
*/
|
|
if (rw == WRITE)
|
|
atomic_inc(&inode->i_dio_count);
|
|
|
|
/* If we do a overwrite dio, i_mutex locking can be released */
|
|
overwrite = *((int *)iocb->private);
|
|
|
|
if (overwrite) {
|
|
down_read(&EXT4_I(inode)->i_data_sem);
|
|
mutex_unlock(&inode->i_mutex);
|
|
}
|
|
|
|
/*
|
|
* We could direct write to holes and fallocate.
|
|
*
|
|
* Allocated blocks to fill the hole are marked as
|
|
* uninitialized to prevent parallel buffered read to expose
|
|
* the stale data before DIO complete the data IO.
|
|
*
|
|
* As to previously fallocated extents, ext4 get_block will
|
|
* just simply mark the buffer mapped but still keep the
|
|
* extents uninitialized.
|
|
*
|
|
* For non AIO case, we will convert those unwritten extents
|
|
* to written after return back from blockdev_direct_IO.
|
|
*
|
|
* For async DIO, the conversion needs to be deferred when the
|
|
* IO is completed. The ext4 end_io callback function will be
|
|
* called to take care of the conversion work. Here for async
|
|
* case, we allocate an io_end structure to hook to the iocb.
|
|
*/
|
|
iocb->private = NULL;
|
|
ext4_inode_aio_set(inode, NULL);
|
|
if (!is_sync_kiocb(iocb)) {
|
|
io_end = ext4_init_io_end(inode, GFP_NOFS);
|
|
if (!io_end) {
|
|
ret = -ENOMEM;
|
|
goto retake_lock;
|
|
}
|
|
/*
|
|
* Grab reference for DIO. Will be dropped in ext4_end_io_dio()
|
|
*/
|
|
iocb->private = ext4_get_io_end(io_end);
|
|
/*
|
|
* we save the io structure for current async direct
|
|
* IO, so that later ext4_map_blocks() could flag the
|
|
* io structure whether there is a unwritten extents
|
|
* needs to be converted when IO is completed.
|
|
*/
|
|
ext4_inode_aio_set(inode, io_end);
|
|
}
|
|
|
|
if (overwrite) {
|
|
get_block_func = ext4_get_block_write_nolock;
|
|
} else {
|
|
get_block_func = ext4_get_block_write;
|
|
dio_flags = DIO_LOCKING;
|
|
}
|
|
ret = __blockdev_direct_IO(rw, iocb, inode,
|
|
inode->i_sb->s_bdev, iov,
|
|
offset, nr_segs,
|
|
get_block_func,
|
|
ext4_end_io_dio,
|
|
NULL,
|
|
dio_flags);
|
|
|
|
/*
|
|
* Put our reference to io_end. This can free the io_end structure e.g.
|
|
* in sync IO case or in case of error. It can even perform extent
|
|
* conversion if all bios we submitted finished before we got here.
|
|
* Note that in that case iocb->private can be already set to NULL
|
|
* here.
|
|
*/
|
|
if (io_end) {
|
|
ext4_inode_aio_set(inode, NULL);
|
|
ext4_put_io_end(io_end);
|
|
/*
|
|
* When no IO was submitted ext4_end_io_dio() was not
|
|
* called so we have to put iocb's reference.
|
|
*/
|
|
if (ret <= 0 && ret != -EIOCBQUEUED && iocb->private) {
|
|
WARN_ON(iocb->private != io_end);
|
|
WARN_ON(io_end->flag & EXT4_IO_END_UNWRITTEN);
|
|
ext4_put_io_end(io_end);
|
|
iocb->private = NULL;
|
|
}
|
|
}
|
|
if (ret > 0 && !overwrite && ext4_test_inode_state(inode,
|
|
EXT4_STATE_DIO_UNWRITTEN)) {
|
|
int err;
|
|
/*
|
|
* for non AIO case, since the IO is already
|
|
* completed, we could do the conversion right here
|
|
*/
|
|
err = ext4_convert_unwritten_extents(NULL, inode,
|
|
offset, ret);
|
|
if (err < 0)
|
|
ret = err;
|
|
ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
|
|
}
|
|
|
|
retake_lock:
|
|
if (rw == WRITE)
|
|
inode_dio_done(inode);
|
|
/* take i_mutex locking again if we do a ovewrite dio */
|
|
if (overwrite) {
|
|
up_read(&EXT4_I(inode)->i_data_sem);
|
|
mutex_lock(&inode->i_mutex);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
ssize_t ret;
|
|
|
|
/*
|
|
* If we are doing data journalling we don't support O_DIRECT
|
|
*/
|
|
if (ext4_should_journal_data(inode))
|
|
return 0;
|
|
|
|
/* Let buffer I/O handle the inline data case. */
|
|
if (ext4_has_inline_data(inode))
|
|
return 0;
|
|
|
|
trace_ext4_direct_IO_enter(inode, offset, iov_length(iov, nr_segs), rw);
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
ret = ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
else
|
|
ret = ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
|
|
trace_ext4_direct_IO_exit(inode, offset,
|
|
iov_length(iov, nr_segs), rw, ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Pages can be marked dirty completely asynchronously from ext4's journalling
|
|
* activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
|
|
* much here because ->set_page_dirty is called under VFS locks. The page is
|
|
* not necessarily locked.
|
|
*
|
|
* We cannot just dirty the page and leave attached buffers clean, because the
|
|
* buffers' dirty state is "definitive". We cannot just set the buffers dirty
|
|
* or jbddirty because all the journalling code will explode.
|
|
*
|
|
* So what we do is to mark the page "pending dirty" and next time writepage
|
|
* is called, propagate that into the buffers appropriately.
|
|
*/
|
|
static int ext4_journalled_set_page_dirty(struct page *page)
|
|
{
|
|
SetPageChecked(page);
|
|
return __set_page_dirty_nobuffers(page);
|
|
}
|
|
|
|
static const struct address_space_operations ext4_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.writepages = ext4_writepages,
|
|
.write_begin = ext4_write_begin,
|
|
.write_end = ext4_write_end,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations ext4_journalled_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.writepages = ext4_writepages,
|
|
.write_begin = ext4_write_begin,
|
|
.write_end = ext4_journalled_write_end,
|
|
.set_page_dirty = ext4_journalled_set_page_dirty,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_journalled_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations ext4_da_aops = {
|
|
.readpage = ext4_readpage,
|
|
.readpages = ext4_readpages,
|
|
.writepage = ext4_writepage,
|
|
.writepages = ext4_writepages,
|
|
.write_begin = ext4_da_write_begin,
|
|
.write_end = ext4_da_write_end,
|
|
.bmap = ext4_bmap,
|
|
.invalidatepage = ext4_da_invalidatepage,
|
|
.releasepage = ext4_releasepage,
|
|
.direct_IO = ext4_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
void ext4_set_aops(struct inode *inode)
|
|
{
|
|
switch (ext4_inode_journal_mode(inode)) {
|
|
case EXT4_INODE_ORDERED_DATA_MODE:
|
|
ext4_set_inode_state(inode, EXT4_STATE_ORDERED_MODE);
|
|
break;
|
|
case EXT4_INODE_WRITEBACK_DATA_MODE:
|
|
ext4_clear_inode_state(inode, EXT4_STATE_ORDERED_MODE);
|
|
break;
|
|
case EXT4_INODE_JOURNAL_DATA_MODE:
|
|
inode->i_mapping->a_ops = &ext4_journalled_aops;
|
|
return;
|
|
default:
|
|
BUG();
|
|
}
|
|
if (test_opt(inode->i_sb, DELALLOC))
|
|
inode->i_mapping->a_ops = &ext4_da_aops;
|
|
else
|
|
inode->i_mapping->a_ops = &ext4_aops;
|
|
}
|
|
|
|
/*
|
|
* ext4_block_truncate_page() zeroes out a mapping from file offset `from'
|
|
* up to the end of the block which corresponds to `from'.
|
|
* This required during truncate. We need to physically zero the tail end
|
|
* of that block so it doesn't yield old data if the file is later grown.
|
|
*/
|
|
int ext4_block_truncate_page(handle_t *handle,
|
|
struct address_space *mapping, loff_t from)
|
|
{
|
|
unsigned offset = from & (PAGE_CACHE_SIZE-1);
|
|
unsigned length;
|
|
unsigned blocksize;
|
|
struct inode *inode = mapping->host;
|
|
|
|
blocksize = inode->i_sb->s_blocksize;
|
|
length = blocksize - (offset & (blocksize - 1));
|
|
|
|
return ext4_block_zero_page_range(handle, mapping, from, length);
|
|
}
|
|
|
|
/*
|
|
* ext4_block_zero_page_range() zeros out a mapping of length 'length'
|
|
* starting from file offset 'from'. The range to be zero'd must
|
|
* be contained with in one block. If the specified range exceeds
|
|
* the end of the block it will be shortened to end of the block
|
|
* that cooresponds to 'from'
|
|
*/
|
|
int ext4_block_zero_page_range(handle_t *handle,
|
|
struct address_space *mapping, loff_t from, loff_t length)
|
|
{
|
|
ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
|
|
unsigned offset = from & (PAGE_CACHE_SIZE-1);
|
|
unsigned blocksize, max, pos;
|
|
ext4_lblk_t iblock;
|
|
struct inode *inode = mapping->host;
|
|
struct buffer_head *bh;
|
|
struct page *page;
|
|
int err = 0;
|
|
|
|
page = find_or_create_page(mapping, from >> PAGE_CACHE_SHIFT,
|
|
mapping_gfp_mask(mapping) & ~__GFP_FS);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
blocksize = inode->i_sb->s_blocksize;
|
|
max = blocksize - (offset & (blocksize - 1));
|
|
|
|
/*
|
|
* correct length if it does not fall between
|
|
* 'from' and the end of the block
|
|
*/
|
|
if (length > max || length < 0)
|
|
length = max;
|
|
|
|
iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
|
|
|
|
if (!page_has_buffers(page))
|
|
create_empty_buffers(page, blocksize, 0);
|
|
|
|
/* Find the buffer that contains "offset" */
|
|
bh = page_buffers(page);
|
|
pos = blocksize;
|
|
while (offset >= pos) {
|
|
bh = bh->b_this_page;
|
|
iblock++;
|
|
pos += blocksize;
|
|
}
|
|
if (buffer_freed(bh)) {
|
|
BUFFER_TRACE(bh, "freed: skip");
|
|
goto unlock;
|
|
}
|
|
if (!buffer_mapped(bh)) {
|
|
BUFFER_TRACE(bh, "unmapped");
|
|
ext4_get_block(inode, iblock, bh, 0);
|
|
/* unmapped? It's a hole - nothing to do */
|
|
if (!buffer_mapped(bh)) {
|
|
BUFFER_TRACE(bh, "still unmapped");
|
|
goto unlock;
|
|
}
|
|
}
|
|
|
|
/* Ok, it's mapped. Make sure it's up-to-date */
|
|
if (PageUptodate(page))
|
|
set_buffer_uptodate(bh);
|
|
|
|
if (!buffer_uptodate(bh)) {
|
|
err = -EIO;
|
|
ll_rw_block(READ, 1, &bh);
|
|
wait_on_buffer(bh);
|
|
/* Uhhuh. Read error. Complain and punt. */
|
|
if (!buffer_uptodate(bh))
|
|
goto unlock;
|
|
}
|
|
if (ext4_should_journal_data(inode)) {
|
|
BUFFER_TRACE(bh, "get write access");
|
|
err = ext4_journal_get_write_access(handle, bh);
|
|
if (err)
|
|
goto unlock;
|
|
}
|
|
zero_user(page, offset, length);
|
|
BUFFER_TRACE(bh, "zeroed end of block");
|
|
|
|
if (ext4_should_journal_data(inode)) {
|
|
err = ext4_handle_dirty_metadata(handle, inode, bh);
|
|
} else {
|
|
err = 0;
|
|
mark_buffer_dirty(bh);
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_ORDERED_MODE))
|
|
err = ext4_jbd2_file_inode(handle, inode);
|
|
}
|
|
|
|
unlock:
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
return err;
|
|
}
|
|
|
|
int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode,
|
|
loff_t lstart, loff_t length)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
unsigned partial_start, partial_end;
|
|
ext4_fsblk_t start, end;
|
|
loff_t byte_end = (lstart + length - 1);
|
|
int err = 0;
|
|
|
|
partial_start = lstart & (sb->s_blocksize - 1);
|
|
partial_end = byte_end & (sb->s_blocksize - 1);
|
|
|
|
start = lstart >> sb->s_blocksize_bits;
|
|
end = byte_end >> sb->s_blocksize_bits;
|
|
|
|
/* Handle partial zero within the single block */
|
|
if (start == end &&
|
|
(partial_start || (partial_end != sb->s_blocksize - 1))) {
|
|
err = ext4_block_zero_page_range(handle, mapping,
|
|
lstart, length);
|
|
return err;
|
|
}
|
|
/* Handle partial zero out on the start of the range */
|
|
if (partial_start) {
|
|
err = ext4_block_zero_page_range(handle, mapping,
|
|
lstart, sb->s_blocksize);
|
|
if (err)
|
|
return err;
|
|
}
|
|
/* Handle partial zero out on the end of the range */
|
|
if (partial_end != sb->s_blocksize - 1)
|
|
err = ext4_block_zero_page_range(handle, mapping,
|
|
byte_end - partial_end,
|
|
partial_end + 1);
|
|
return err;
|
|
}
|
|
|
|
int ext4_can_truncate(struct inode *inode)
|
|
{
|
|
if (S_ISREG(inode->i_mode))
|
|
return 1;
|
|
if (S_ISDIR(inode->i_mode))
|
|
return 1;
|
|
if (S_ISLNK(inode->i_mode))
|
|
return !ext4_inode_is_fast_symlink(inode);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ext4_punch_hole: punches a hole in a file by releaseing the blocks
|
|
* associated with the given offset and length
|
|
*
|
|
* @inode: File inode
|
|
* @offset: The offset where the hole will begin
|
|
* @len: The length of the hole
|
|
*
|
|
* Returns: 0 on success or negative on failure
|
|
*/
|
|
|
|
int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
|
|
{
|
|
struct super_block *sb = inode->i_sb;
|
|
ext4_lblk_t first_block, stop_block;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
loff_t first_block_offset, last_block_offset;
|
|
handle_t *handle;
|
|
unsigned int credits;
|
|
int ret = 0;
|
|
|
|
if (!S_ISREG(inode->i_mode))
|
|
return -EOPNOTSUPP;
|
|
|
|
trace_ext4_punch_hole(inode, offset, length);
|
|
|
|
/*
|
|
* Write out all dirty pages to avoid race conditions
|
|
* Then release them.
|
|
*/
|
|
if (mapping->nrpages && mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
|
|
ret = filemap_write_and_wait_range(mapping, offset,
|
|
offset + length - 1);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
/* It's not possible punch hole on append only file */
|
|
if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) {
|
|
ret = -EPERM;
|
|
goto out_mutex;
|
|
}
|
|
if (IS_SWAPFILE(inode)) {
|
|
ret = -ETXTBSY;
|
|
goto out_mutex;
|
|
}
|
|
|
|
/* No need to punch hole beyond i_size */
|
|
if (offset >= inode->i_size)
|
|
goto out_mutex;
|
|
|
|
/*
|
|
* If the hole extends beyond i_size, set the hole
|
|
* to end after the page that contains i_size
|
|
*/
|
|
if (offset + length > inode->i_size) {
|
|
length = inode->i_size +
|
|
PAGE_CACHE_SIZE - (inode->i_size & (PAGE_CACHE_SIZE - 1)) -
|
|
offset;
|
|
}
|
|
|
|
if (offset & (sb->s_blocksize - 1) ||
|
|
(offset + length) & (sb->s_blocksize - 1)) {
|
|
/*
|
|
* Attach jinode to inode for jbd2 if we do any zeroing of
|
|
* partial block
|
|
*/
|
|
ret = ext4_inode_attach_jinode(inode);
|
|
if (ret < 0)
|
|
goto out_mutex;
|
|
|
|
}
|
|
|
|
first_block_offset = round_up(offset, sb->s_blocksize);
|
|
last_block_offset = round_down((offset + length), sb->s_blocksize) - 1;
|
|
|
|
/* Now release the pages and zero block aligned part of pages*/
|
|
if (last_block_offset > first_block_offset)
|
|
truncate_pagecache_range(inode, first_block_offset,
|
|
last_block_offset);
|
|
|
|
/* Wait all existing dio workers, newcomers will block on i_mutex */
|
|
ext4_inode_block_unlocked_dio(inode);
|
|
inode_dio_wait(inode);
|
|
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
credits = ext4_writepage_trans_blocks(inode);
|
|
else
|
|
credits = ext4_blocks_for_truncate(inode);
|
|
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
|
|
if (IS_ERR(handle)) {
|
|
ret = PTR_ERR(handle);
|
|
ext4_std_error(sb, ret);
|
|
goto out_dio;
|
|
}
|
|
|
|
ret = ext4_zero_partial_blocks(handle, inode, offset,
|
|
length);
|
|
if (ret)
|
|
goto out_stop;
|
|
|
|
first_block = (offset + sb->s_blocksize - 1) >>
|
|
EXT4_BLOCK_SIZE_BITS(sb);
|
|
stop_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb);
|
|
|
|
/* If there are no blocks to remove, return now */
|
|
if (first_block >= stop_block)
|
|
goto out_stop;
|
|
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
ext4_discard_preallocations(inode);
|
|
|
|
ret = ext4_es_remove_extent(inode, first_block,
|
|
stop_block - first_block);
|
|
if (ret) {
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
goto out_stop;
|
|
}
|
|
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
ret = ext4_ext_remove_space(inode, first_block,
|
|
stop_block - 1);
|
|
else
|
|
ret = ext4_free_hole_blocks(handle, inode, first_block,
|
|
stop_block);
|
|
|
|
ext4_discard_preallocations(inode);
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
if (IS_SYNC(inode))
|
|
ext4_handle_sync(handle);
|
|
inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
out_stop:
|
|
ext4_journal_stop(handle);
|
|
out_dio:
|
|
ext4_inode_resume_unlocked_dio(inode);
|
|
out_mutex:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
|
|
int ext4_inode_attach_jinode(struct inode *inode)
|
|
{
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
struct jbd2_inode *jinode;
|
|
|
|
if (ei->jinode || !EXT4_SB(inode->i_sb)->s_journal)
|
|
return 0;
|
|
|
|
jinode = jbd2_alloc_inode(GFP_KERNEL);
|
|
spin_lock(&inode->i_lock);
|
|
if (!ei->jinode) {
|
|
if (!jinode) {
|
|
spin_unlock(&inode->i_lock);
|
|
return -ENOMEM;
|
|
}
|
|
ei->jinode = jinode;
|
|
jbd2_journal_init_jbd_inode(ei->jinode, inode);
|
|
jinode = NULL;
|
|
}
|
|
spin_unlock(&inode->i_lock);
|
|
if (unlikely(jinode != NULL))
|
|
jbd2_free_inode(jinode);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ext4_truncate()
|
|
*
|
|
* We block out ext4_get_block() block instantiations across the entire
|
|
* transaction, and VFS/VM ensures that ext4_truncate() cannot run
|
|
* simultaneously on behalf of the same inode.
|
|
*
|
|
* As we work through the truncate and commit bits of it to the journal there
|
|
* is one core, guiding principle: the file's tree must always be consistent on
|
|
* disk. We must be able to restart the truncate after a crash.
|
|
*
|
|
* The file's tree may be transiently inconsistent in memory (although it
|
|
* probably isn't), but whenever we close off and commit a journal transaction,
|
|
* the contents of (the filesystem + the journal) must be consistent and
|
|
* restartable. It's pretty simple, really: bottom up, right to left (although
|
|
* left-to-right works OK too).
|
|
*
|
|
* Note that at recovery time, journal replay occurs *before* the restart of
|
|
* truncate against the orphan inode list.
|
|
*
|
|
* The committed inode has the new, desired i_size (which is the same as
|
|
* i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
|
|
* that this inode's truncate did not complete and it will again call
|
|
* ext4_truncate() to have another go. So there will be instantiated blocks
|
|
* to the right of the truncation point in a crashed ext4 filesystem. But
|
|
* that's fine - as long as they are linked from the inode, the post-crash
|
|
* ext4_truncate() run will find them and release them.
|
|
*/
|
|
void ext4_truncate(struct inode *inode)
|
|
{
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
unsigned int credits;
|
|
handle_t *handle;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
|
|
/*
|
|
* There is a possibility that we're either freeing the inode
|
|
* or it completely new indode. In those cases we might not
|
|
* have i_mutex locked because it's not necessary.
|
|
*/
|
|
if (!(inode->i_state & (I_NEW|I_FREEING)))
|
|
WARN_ON(!mutex_is_locked(&inode->i_mutex));
|
|
trace_ext4_truncate_enter(inode);
|
|
|
|
if (!ext4_can_truncate(inode))
|
|
return;
|
|
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_EOFBLOCKS);
|
|
|
|
if (inode->i_size == 0 && !test_opt(inode->i_sb, NO_AUTO_DA_ALLOC))
|
|
ext4_set_inode_state(inode, EXT4_STATE_DA_ALLOC_CLOSE);
|
|
|
|
if (ext4_has_inline_data(inode)) {
|
|
int has_inline = 1;
|
|
|
|
ext4_inline_data_truncate(inode, &has_inline);
|
|
if (has_inline)
|
|
return;
|
|
}
|
|
|
|
/* If we zero-out tail of the page, we have to create jinode for jbd2 */
|
|
if (inode->i_size & (inode->i_sb->s_blocksize - 1)) {
|
|
if (ext4_inode_attach_jinode(inode) < 0)
|
|
return;
|
|
}
|
|
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
credits = ext4_writepage_trans_blocks(inode);
|
|
else
|
|
credits = ext4_blocks_for_truncate(inode);
|
|
|
|
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE, credits);
|
|
if (IS_ERR(handle)) {
|
|
ext4_std_error(inode->i_sb, PTR_ERR(handle));
|
|
return;
|
|
}
|
|
|
|
if (inode->i_size & (inode->i_sb->s_blocksize - 1))
|
|
ext4_block_truncate_page(handle, mapping, inode->i_size);
|
|
|
|
/*
|
|
* We add the inode to the orphan list, so that if this
|
|
* truncate spans multiple transactions, and we crash, we will
|
|
* resume the truncate when the filesystem recovers. It also
|
|
* marks the inode dirty, to catch the new size.
|
|
*
|
|
* Implication: the file must always be in a sane, consistent
|
|
* truncatable state while each transaction commits.
|
|
*/
|
|
if (ext4_orphan_add(handle, inode))
|
|
goto out_stop;
|
|
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
|
|
ext4_discard_preallocations(inode);
|
|
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
|
|
ext4_ext_truncate(handle, inode);
|
|
else
|
|
ext4_ind_truncate(handle, inode);
|
|
|
|
up_write(&ei->i_data_sem);
|
|
|
|
if (IS_SYNC(inode))
|
|
ext4_handle_sync(handle);
|
|
|
|
out_stop:
|
|
/*
|
|
* If this was a simple ftruncate() and the file will remain alive,
|
|
* then we need to clear up the orphan record which we created above.
|
|
* However, if this was a real unlink then we were called by
|
|
* ext4_delete_inode(), and we allow that function to clean up the
|
|
* orphan info for us.
|
|
*/
|
|
if (inode->i_nlink)
|
|
ext4_orphan_del(handle, inode);
|
|
|
|
inode->i_mtime = inode->i_ctime = ext4_current_time(inode);
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
ext4_journal_stop(handle);
|
|
|
|
trace_ext4_truncate_exit(inode);
|
|
}
|
|
|
|
/*
|
|
* ext4_get_inode_loc returns with an extra refcount against the inode's
|
|
* underlying buffer_head on success. If 'in_mem' is true, we have all
|
|
* data in memory that is needed to recreate the on-disk version of this
|
|
* inode.
|
|
*/
|
|
static int __ext4_get_inode_loc(struct inode *inode,
|
|
struct ext4_iloc *iloc, int in_mem)
|
|
{
|
|
struct ext4_group_desc *gdp;
|
|
struct buffer_head *bh;
|
|
struct super_block *sb = inode->i_sb;
|
|
ext4_fsblk_t block;
|
|
int inodes_per_block, inode_offset;
|
|
|
|
iloc->bh = NULL;
|
|
if (!ext4_valid_inum(sb, inode->i_ino))
|
|
return -EIO;
|
|
|
|
iloc->block_group = (inode->i_ino - 1) / EXT4_INODES_PER_GROUP(sb);
|
|
gdp = ext4_get_group_desc(sb, iloc->block_group, NULL);
|
|
if (!gdp)
|
|
return -EIO;
|
|
|
|
/*
|
|
* Figure out the offset within the block group inode table
|
|
*/
|
|
inodes_per_block = EXT4_SB(sb)->s_inodes_per_block;
|
|
inode_offset = ((inode->i_ino - 1) %
|
|
EXT4_INODES_PER_GROUP(sb));
|
|
block = ext4_inode_table(sb, gdp) + (inode_offset / inodes_per_block);
|
|
iloc->offset = (inode_offset % inodes_per_block) * EXT4_INODE_SIZE(sb);
|
|
|
|
bh = sb_getblk(sb, block);
|
|
if (unlikely(!bh))
|
|
return -ENOMEM;
|
|
if (!buffer_uptodate(bh)) {
|
|
lock_buffer(bh);
|
|
|
|
/*
|
|
* If the buffer has the write error flag, we have failed
|
|
* to write out another inode in the same block. In this
|
|
* case, we don't have to read the block because we may
|
|
* read the old inode data successfully.
|
|
*/
|
|
if (buffer_write_io_error(bh) && !buffer_uptodate(bh))
|
|
set_buffer_uptodate(bh);
|
|
|
|
if (buffer_uptodate(bh)) {
|
|
/* someone brought it uptodate while we waited */
|
|
unlock_buffer(bh);
|
|
goto has_buffer;
|
|
}
|
|
|
|
/*
|
|
* If we have all information of the inode in memory and this
|
|
* is the only valid inode in the block, we need not read the
|
|
* block.
|
|
*/
|
|
if (in_mem) {
|
|
struct buffer_head *bitmap_bh;
|
|
int i, start;
|
|
|
|
start = inode_offset & ~(inodes_per_block - 1);
|
|
|
|
/* Is the inode bitmap in cache? */
|
|
bitmap_bh = sb_getblk(sb, ext4_inode_bitmap(sb, gdp));
|
|
if (unlikely(!bitmap_bh))
|
|
goto make_io;
|
|
|
|
/*
|
|
* If the inode bitmap isn't in cache then the
|
|
* optimisation may end up performing two reads instead
|
|
* of one, so skip it.
|
|
*/
|
|
if (!buffer_uptodate(bitmap_bh)) {
|
|
brelse(bitmap_bh);
|
|
goto make_io;
|
|
}
|
|
for (i = start; i < start + inodes_per_block; i++) {
|
|
if (i == inode_offset)
|
|
continue;
|
|
if (ext4_test_bit(i, bitmap_bh->b_data))
|
|
break;
|
|
}
|
|
brelse(bitmap_bh);
|
|
if (i == start + inodes_per_block) {
|
|
/* all other inodes are free, so skip I/O */
|
|
memset(bh->b_data, 0, bh->b_size);
|
|
set_buffer_uptodate(bh);
|
|
unlock_buffer(bh);
|
|
goto has_buffer;
|
|
}
|
|
}
|
|
|
|
make_io:
|
|
/*
|
|
* If we need to do any I/O, try to pre-readahead extra
|
|
* blocks from the inode table.
|
|
*/
|
|
if (EXT4_SB(sb)->s_inode_readahead_blks) {
|
|
ext4_fsblk_t b, end, table;
|
|
unsigned num;
|
|
__u32 ra_blks = EXT4_SB(sb)->s_inode_readahead_blks;
|
|
|
|
table = ext4_inode_table(sb, gdp);
|
|
/* s_inode_readahead_blks is always a power of 2 */
|
|
b = block & ~((ext4_fsblk_t) ra_blks - 1);
|
|
if (table > b)
|
|
b = table;
|
|
end = b + ra_blks;
|
|
num = EXT4_INODES_PER_GROUP(sb);
|
|
if (ext4_has_group_desc_csum(sb))
|
|
num -= ext4_itable_unused_count(sb, gdp);
|
|
table += num / inodes_per_block;
|
|
if (end > table)
|
|
end = table;
|
|
while (b <= end)
|
|
sb_breadahead(sb, b++);
|
|
}
|
|
|
|
/*
|
|
* There are other valid inodes in the buffer, this inode
|
|
* has in-inode xattrs, or we don't have this inode in memory.
|
|
* Read the block from disk.
|
|
*/
|
|
trace_ext4_load_inode(inode);
|
|
get_bh(bh);
|
|
bh->b_end_io = end_buffer_read_sync;
|
|
submit_bh(READ | REQ_META | REQ_PRIO, bh);
|
|
wait_on_buffer(bh);
|
|
if (!buffer_uptodate(bh)) {
|
|
EXT4_ERROR_INODE_BLOCK(inode, block,
|
|
"unable to read itable block");
|
|
brelse(bh);
|
|
return -EIO;
|
|
}
|
|
}
|
|
has_buffer:
|
|
iloc->bh = bh;
|
|
return 0;
|
|
}
|
|
|
|
int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
|
|
{
|
|
/* We have all inode data except xattrs in memory here. */
|
|
return __ext4_get_inode_loc(inode, iloc,
|
|
!ext4_test_inode_state(inode, EXT4_STATE_XATTR));
|
|
}
|
|
|
|
void ext4_set_inode_flags(struct inode *inode)
|
|
{
|
|
unsigned int flags = EXT4_I(inode)->i_flags;
|
|
unsigned int new_fl = 0;
|
|
|
|
if (flags & EXT4_SYNC_FL)
|
|
new_fl |= S_SYNC;
|
|
if (flags & EXT4_APPEND_FL)
|
|
new_fl |= S_APPEND;
|
|
if (flags & EXT4_IMMUTABLE_FL)
|
|
new_fl |= S_IMMUTABLE;
|
|
if (flags & EXT4_NOATIME_FL)
|
|
new_fl |= S_NOATIME;
|
|
if (flags & EXT4_DIRSYNC_FL)
|
|
new_fl |= S_DIRSYNC;
|
|
set_mask_bits(&inode->i_flags,
|
|
S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC, new_fl);
|
|
}
|
|
|
|
/* Propagate flags from i_flags to EXT4_I(inode)->i_flags */
|
|
void ext4_get_inode_flags(struct ext4_inode_info *ei)
|
|
{
|
|
unsigned int vfs_fl;
|
|
unsigned long old_fl, new_fl;
|
|
|
|
do {
|
|
vfs_fl = ei->vfs_inode.i_flags;
|
|
old_fl = ei->i_flags;
|
|
new_fl = old_fl & ~(EXT4_SYNC_FL|EXT4_APPEND_FL|
|
|
EXT4_IMMUTABLE_FL|EXT4_NOATIME_FL|
|
|
EXT4_DIRSYNC_FL);
|
|
if (vfs_fl & S_SYNC)
|
|
new_fl |= EXT4_SYNC_FL;
|
|
if (vfs_fl & S_APPEND)
|
|
new_fl |= EXT4_APPEND_FL;
|
|
if (vfs_fl & S_IMMUTABLE)
|
|
new_fl |= EXT4_IMMUTABLE_FL;
|
|
if (vfs_fl & S_NOATIME)
|
|
new_fl |= EXT4_NOATIME_FL;
|
|
if (vfs_fl & S_DIRSYNC)
|
|
new_fl |= EXT4_DIRSYNC_FL;
|
|
} while (cmpxchg(&ei->i_flags, old_fl, new_fl) != old_fl);
|
|
}
|
|
|
|
static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
blkcnt_t i_blocks ;
|
|
struct inode *inode = &(ei->vfs_inode);
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
|
|
/* we are using combined 48 bit field */
|
|
i_blocks = ((u64)le16_to_cpu(raw_inode->i_blocks_high)) << 32 |
|
|
le32_to_cpu(raw_inode->i_blocks_lo);
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_HUGE_FILE)) {
|
|
/* i_blocks represent file system block size */
|
|
return i_blocks << (inode->i_blkbits - 9);
|
|
} else {
|
|
return i_blocks;
|
|
}
|
|
} else {
|
|
return le32_to_cpu(raw_inode->i_blocks_lo);
|
|
}
|
|
}
|
|
|
|
static inline void ext4_iget_extra_inode(struct inode *inode,
|
|
struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
__le32 *magic = (void *)raw_inode +
|
|
EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize;
|
|
if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC)) {
|
|
ext4_set_inode_state(inode, EXT4_STATE_XATTR);
|
|
ext4_find_inline_data_nolock(inode);
|
|
} else
|
|
EXT4_I(inode)->i_inline_off = 0;
|
|
}
|
|
|
|
struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
struct ext4_inode *raw_inode;
|
|
struct ext4_inode_info *ei;
|
|
struct inode *inode;
|
|
journal_t *journal = EXT4_SB(sb)->s_journal;
|
|
long ret;
|
|
int block;
|
|
uid_t i_uid;
|
|
gid_t i_gid;
|
|
|
|
inode = iget_locked(sb, ino);
|
|
if (!inode)
|
|
return ERR_PTR(-ENOMEM);
|
|
if (!(inode->i_state & I_NEW))
|
|
return inode;
|
|
|
|
ei = EXT4_I(inode);
|
|
iloc.bh = NULL;
|
|
|
|
ret = __ext4_get_inode_loc(inode, &iloc, 0);
|
|
if (ret < 0)
|
|
goto bad_inode;
|
|
raw_inode = ext4_raw_inode(&iloc);
|
|
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
|
|
if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
|
|
EXT4_INODE_SIZE(inode->i_sb)) {
|
|
EXT4_ERROR_INODE(inode, "bad extra_isize (%u != %u)",
|
|
EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize,
|
|
EXT4_INODE_SIZE(inode->i_sb));
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
}
|
|
} else
|
|
ei->i_extra_isize = 0;
|
|
|
|
/* Precompute checksum seed for inode metadata */
|
|
if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
__u32 csum;
|
|
__le32 inum = cpu_to_le32(inode->i_ino);
|
|
__le32 gen = raw_inode->i_generation;
|
|
csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&inum,
|
|
sizeof(inum));
|
|
ei->i_csum_seed = ext4_chksum(sbi, csum, (__u8 *)&gen,
|
|
sizeof(gen));
|
|
}
|
|
|
|
if (!ext4_inode_csum_verify(inode, raw_inode, ei)) {
|
|
EXT4_ERROR_INODE(inode, "checksum invalid");
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
}
|
|
|
|
inode->i_mode = le16_to_cpu(raw_inode->i_mode);
|
|
i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
|
|
i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
|
|
if (!(test_opt(inode->i_sb, NO_UID32))) {
|
|
i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
|
|
i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
|
|
}
|
|
i_uid_write(inode, i_uid);
|
|
i_gid_write(inode, i_gid);
|
|
set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
|
|
|
|
ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */
|
|
ei->i_inline_off = 0;
|
|
ei->i_dir_start_lookup = 0;
|
|
ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
|
|
/* We now have enough fields to check if the inode was active or not.
|
|
* This is needed because nfsd might try to access dead inodes
|
|
* the test is that same one that e2fsck uses
|
|
* NeilBrown 1999oct15
|
|
*/
|
|
if (inode->i_nlink == 0) {
|
|
if ((inode->i_mode == 0 ||
|
|
!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) &&
|
|
ino != EXT4_BOOT_LOADER_INO) {
|
|
/* this inode is deleted */
|
|
ret = -ESTALE;
|
|
goto bad_inode;
|
|
}
|
|
/* The only unlinked inodes we let through here have
|
|
* valid i_mode and are being read by the orphan
|
|
* recovery code: that's fine, we're about to complete
|
|
* the process of deleting those.
|
|
* OR it is the EXT4_BOOT_LOADER_INO which is
|
|
* not initialized on a new filesystem. */
|
|
}
|
|
ei->i_flags = le32_to_cpu(raw_inode->i_flags);
|
|
inode->i_blocks = ext4_inode_blocks(raw_inode, ei);
|
|
ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl_lo);
|
|
if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT))
|
|
ei->i_file_acl |=
|
|
((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
|
|
inode->i_size = ext4_isize(raw_inode);
|
|
ei->i_disksize = inode->i_size;
|
|
#ifdef CONFIG_QUOTA
|
|
ei->i_reserved_quota = 0;
|
|
#endif
|
|
inode->i_generation = le32_to_cpu(raw_inode->i_generation);
|
|
ei->i_block_group = iloc.block_group;
|
|
ei->i_last_alloc_group = ~0;
|
|
/*
|
|
* NOTE! The in-memory inode i_data array is in little-endian order
|
|
* even on big-endian machines: we do NOT byteswap the block numbers!
|
|
*/
|
|
for (block = 0; block < EXT4_N_BLOCKS; block++)
|
|
ei->i_data[block] = raw_inode->i_block[block];
|
|
INIT_LIST_HEAD(&ei->i_orphan);
|
|
|
|
/*
|
|
* Set transaction id's of transactions that have to be committed
|
|
* to finish f[data]sync. We set them to currently running transaction
|
|
* as we cannot be sure that the inode or some of its metadata isn't
|
|
* part of the transaction - the inode could have been reclaimed and
|
|
* now it is reread from disk.
|
|
*/
|
|
if (journal) {
|
|
transaction_t *transaction;
|
|
tid_t tid;
|
|
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_running_transaction)
|
|
transaction = journal->j_running_transaction;
|
|
else
|
|
transaction = journal->j_committing_transaction;
|
|
if (transaction)
|
|
tid = transaction->t_tid;
|
|
else
|
|
tid = journal->j_commit_sequence;
|
|
read_unlock(&journal->j_state_lock);
|
|
ei->i_sync_tid = tid;
|
|
ei->i_datasync_tid = tid;
|
|
}
|
|
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
if (ei->i_extra_isize == 0) {
|
|
/* The extra space is currently unused. Use it. */
|
|
ei->i_extra_isize = sizeof(struct ext4_inode) -
|
|
EXT4_GOOD_OLD_INODE_SIZE;
|
|
} else {
|
|
ext4_iget_extra_inode(inode, raw_inode, ei);
|
|
}
|
|
}
|
|
|
|
EXT4_INODE_GET_XTIME(i_ctime, inode, raw_inode);
|
|
EXT4_INODE_GET_XTIME(i_mtime, inode, raw_inode);
|
|
EXT4_INODE_GET_XTIME(i_atime, inode, raw_inode);
|
|
EXT4_EINODE_GET_XTIME(i_crtime, ei, raw_inode);
|
|
|
|
inode->i_version = le32_to_cpu(raw_inode->i_disk_version);
|
|
if (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
|
|
if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
|
|
inode->i_version |=
|
|
(__u64)(le32_to_cpu(raw_inode->i_version_hi)) << 32;
|
|
}
|
|
|
|
ret = 0;
|
|
if (ei->i_file_acl &&
|
|
!ext4_data_block_valid(EXT4_SB(sb), ei->i_file_acl, 1)) {
|
|
EXT4_ERROR_INODE(inode, "bad extended attribute block %llu",
|
|
ei->i_file_acl);
|
|
ret = -EIO;
|
|
goto bad_inode;
|
|
} else if (!ext4_has_inline_data(inode)) {
|
|
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) {
|
|
if ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
(S_ISLNK(inode->i_mode) &&
|
|
!ext4_inode_is_fast_symlink(inode))))
|
|
/* Validate extent which is part of inode */
|
|
ret = ext4_ext_check_inode(inode);
|
|
} else if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
|
|
(S_ISLNK(inode->i_mode) &&
|
|
!ext4_inode_is_fast_symlink(inode))) {
|
|
/* Validate block references which are part of inode */
|
|
ret = ext4_ind_check_inode(inode);
|
|
}
|
|
}
|
|
if (ret)
|
|
goto bad_inode;
|
|
|
|
if (S_ISREG(inode->i_mode)) {
|
|
inode->i_op = &ext4_file_inode_operations;
|
|
inode->i_fop = &ext4_file_operations;
|
|
ext4_set_aops(inode);
|
|
} else if (S_ISDIR(inode->i_mode)) {
|
|
inode->i_op = &ext4_dir_inode_operations;
|
|
inode->i_fop = &ext4_dir_operations;
|
|
} else if (S_ISLNK(inode->i_mode)) {
|
|
if (ext4_inode_is_fast_symlink(inode)) {
|
|
inode->i_op = &ext4_fast_symlink_inode_operations;
|
|
nd_terminate_link(ei->i_data, inode->i_size,
|
|
sizeof(ei->i_data) - 1);
|
|
} else {
|
|
inode->i_op = &ext4_symlink_inode_operations;
|
|
ext4_set_aops(inode);
|
|
}
|
|
} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
|
|
S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
|
|
inode->i_op = &ext4_special_inode_operations;
|
|
if (raw_inode->i_block[0])
|
|
init_special_inode(inode, inode->i_mode,
|
|
old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
|
|
else
|
|
init_special_inode(inode, inode->i_mode,
|
|
new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
|
|
} else if (ino == EXT4_BOOT_LOADER_INO) {
|
|
make_bad_inode(inode);
|
|
} else {
|
|
ret = -EIO;
|
|
EXT4_ERROR_INODE(inode, "bogus i_mode (%o)", inode->i_mode);
|
|
goto bad_inode;
|
|
}
|
|
brelse(iloc.bh);
|
|
ext4_set_inode_flags(inode);
|
|
unlock_new_inode(inode);
|
|
return inode;
|
|
|
|
bad_inode:
|
|
brelse(iloc.bh);
|
|
iget_failed(inode);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
static int ext4_inode_blocks_set(handle_t *handle,
|
|
struct ext4_inode *raw_inode,
|
|
struct ext4_inode_info *ei)
|
|
{
|
|
struct inode *inode = &(ei->vfs_inode);
|
|
u64 i_blocks = inode->i_blocks;
|
|
struct super_block *sb = inode->i_sb;
|
|
|
|
if (i_blocks <= ~0U) {
|
|
/*
|
|
* i_blocks can be represented in a 32 bit variable
|
|
* as multiple of 512 bytes
|
|
*/
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = 0;
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
return 0;
|
|
}
|
|
if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE))
|
|
return -EFBIG;
|
|
|
|
if (i_blocks <= 0xffffffffffffULL) {
|
|
/*
|
|
* i_blocks can be represented in a 48 bit variable
|
|
* as multiple of 512 bytes
|
|
*/
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
} else {
|
|
ext4_set_inode_flag(inode, EXT4_INODE_HUGE_FILE);
|
|
/* i_block is stored in file system block size */
|
|
i_blocks = i_blocks >> (inode->i_blkbits - 9);
|
|
raw_inode->i_blocks_lo = cpu_to_le32(i_blocks);
|
|
raw_inode->i_blocks_high = cpu_to_le16(i_blocks >> 32);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Post the struct inode info into an on-disk inode location in the
|
|
* buffer-cache. This gobbles the caller's reference to the
|
|
* buffer_head in the inode location struct.
|
|
*
|
|
* The caller must have write access to iloc->bh.
|
|
*/
|
|
static int ext4_do_update_inode(handle_t *handle,
|
|
struct inode *inode,
|
|
struct ext4_iloc *iloc)
|
|
{
|
|
struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
|
|
struct ext4_inode_info *ei = EXT4_I(inode);
|
|
struct buffer_head *bh = iloc->bh;
|
|
int err = 0, rc, block;
|
|
int need_datasync = 0;
|
|
uid_t i_uid;
|
|
gid_t i_gid;
|
|
|
|
/* For fields not not tracking in the in-memory inode,
|
|
* initialise them to zero for new inodes. */
|
|
if (ext4_test_inode_state(inode, EXT4_STATE_NEW))
|
|
memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
|
|
|
|
ext4_get_inode_flags(ei);
|
|
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
|
|
i_uid = i_uid_read(inode);
|
|
i_gid = i_gid_read(inode);
|
|
if (!(test_opt(inode->i_sb, NO_UID32))) {
|
|
raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
|
|
/*
|
|
* Fix up interoperability with old kernels. Otherwise, old inodes get
|
|
* re-used with the upper 16 bits of the uid/gid intact
|
|
*/
|
|
if (!ei->i_dtime) {
|
|
raw_inode->i_uid_high =
|
|
cpu_to_le16(high_16_bits(i_uid));
|
|
raw_inode->i_gid_high =
|
|
cpu_to_le16(high_16_bits(i_gid));
|
|
} else {
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
} else {
|
|
raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(i_uid));
|
|
raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(i_gid));
|
|
raw_inode->i_uid_high = 0;
|
|
raw_inode->i_gid_high = 0;
|
|
}
|
|
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
|
|
|
|
EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode);
|
|
EXT4_INODE_SET_XTIME(i_mtime, inode, raw_inode);
|
|
EXT4_INODE_SET_XTIME(i_atime, inode, raw_inode);
|
|
EXT4_EINODE_SET_XTIME(i_crtime, ei, raw_inode);
|
|
|
|
if (ext4_inode_blocks_set(handle, raw_inode, ei))
|
|
goto out_brelse;
|
|
raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
|
|
raw_inode->i_flags = cpu_to_le32(ei->i_flags & 0xFFFFFFFF);
|
|
if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
|
|
cpu_to_le32(EXT4_OS_HURD))
|
|
raw_inode->i_file_acl_high =
|
|
cpu_to_le16(ei->i_file_acl >> 32);
|
|
raw_inode->i_file_acl_lo = cpu_to_le32(ei->i_file_acl);
|
|
if (ei->i_disksize != ext4_isize(raw_inode)) {
|
|
ext4_isize_set(raw_inode, ei->i_disksize);
|
|
need_datasync = 1;
|
|
}
|
|
if (ei->i_disksize > 0x7fffffffULL) {
|
|
struct super_block *sb = inode->i_sb;
|
|
if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_LARGE_FILE) ||
|
|
EXT4_SB(sb)->s_es->s_rev_level ==
|
|
cpu_to_le32(EXT4_GOOD_OLD_REV)) {
|
|
/* If this is the first large file
|
|
* created, add a flag to the superblock.
|
|
*/
|
|
err = ext4_journal_get_write_access(handle,
|
|
EXT4_SB(sb)->s_sbh);
|
|
if (err)
|
|
goto out_brelse;
|
|
ext4_update_dynamic_rev(sb);
|
|
EXT4_SET_RO_COMPAT_FEATURE(sb,
|
|
EXT4_FEATURE_RO_COMPAT_LARGE_FILE);
|
|
ext4_handle_sync(handle);
|
|
err = ext4_handle_dirty_super(handle, sb);
|
|
}
|
|
}
|
|
raw_inode->i_generation = cpu_to_le32(inode->i_generation);
|
|
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
|
|
if (old_valid_dev(inode->i_rdev)) {
|
|
raw_inode->i_block[0] =
|
|
cpu_to_le32(old_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[1] = 0;
|
|
} else {
|
|
raw_inode->i_block[0] = 0;
|
|
raw_inode->i_block[1] =
|
|
cpu_to_le32(new_encode_dev(inode->i_rdev));
|
|
raw_inode->i_block[2] = 0;
|
|
}
|
|
} else if (!ext4_has_inline_data(inode)) {
|
|
for (block = 0; block < EXT4_N_BLOCKS; block++)
|
|
raw_inode->i_block[block] = ei->i_data[block];
|
|
}
|
|
|
|
raw_inode->i_disk_version = cpu_to_le32(inode->i_version);
|
|
if (ei->i_extra_isize) {
|
|
if (EXT4_FITS_IN_INODE(raw_inode, ei, i_version_hi))
|
|
raw_inode->i_version_hi =
|
|
cpu_to_le32(inode->i_version >> 32);
|
|
raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
|
|
}
|
|
|
|
ext4_inode_csum_set(inode, raw_inode, ei);
|
|
|
|
BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
|
|
rc = ext4_handle_dirty_metadata(handle, NULL, bh);
|
|
if (!err)
|
|
err = rc;
|
|
ext4_clear_inode_state(inode, EXT4_STATE_NEW);
|
|
|
|
ext4_update_inode_fsync_trans(handle, inode, need_datasync);
|
|
out_brelse:
|
|
brelse(bh);
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_write_inode()
|
|
*
|
|
* We are called from a few places:
|
|
*
|
|
* - Within generic_file_write() for O_SYNC files.
|
|
* Here, there will be no transaction running. We wait for any running
|
|
* transaction to commit.
|
|
*
|
|
* - Within sys_sync(), kupdate and such.
|
|
* We wait on commit, if tol to.
|
|
*
|
|
* - Within prune_icache() (PF_MEMALLOC == true)
|
|
* Here we simply return. We can't afford to block kswapd on the
|
|
* journal commit.
|
|
*
|
|
* In all cases it is actually safe for us to return without doing anything,
|
|
* because the inode has been copied into a raw inode buffer in
|
|
* ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
|
|
* knfsd.
|
|
*
|
|
* Note that we are absolutely dependent upon all inode dirtiers doing the
|
|
* right thing: they *must* call mark_inode_dirty() after dirtying info in
|
|
* which we are interested.
|
|
*
|
|
* It would be a bug for them to not do this. The code:
|
|
*
|
|
* mark_inode_dirty(inode)
|
|
* stuff();
|
|
* inode->i_size = expr;
|
|
*
|
|
* is in error because a kswapd-driven write_inode() could occur while
|
|
* `stuff()' is running, and the new i_size will be lost. Plus the inode
|
|
* will no longer be on the superblock's dirty inode list.
|
|
*/
|
|
int ext4_write_inode(struct inode *inode, struct writeback_control *wbc)
|
|
{
|
|
int err;
|
|
|
|
if (current->flags & PF_MEMALLOC)
|
|
return 0;
|
|
|
|
if (EXT4_SB(inode->i_sb)->s_journal) {
|
|
if (ext4_journal_current_handle()) {
|
|
jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n");
|
|
dump_stack();
|
|
return -EIO;
|
|
}
|
|
|
|
if (wbc->sync_mode != WB_SYNC_ALL)
|
|
return 0;
|
|
|
|
err = ext4_force_commit(inode->i_sb);
|
|
} else {
|
|
struct ext4_iloc iloc;
|
|
|
|
err = __ext4_get_inode_loc(inode, &iloc, 0);
|
|
if (err)
|
|
return err;
|
|
if (wbc->sync_mode == WB_SYNC_ALL)
|
|
sync_dirty_buffer(iloc.bh);
|
|
if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
|
|
EXT4_ERROR_INODE_BLOCK(inode, iloc.bh->b_blocknr,
|
|
"IO error syncing inode");
|
|
err = -EIO;
|
|
}
|
|
brelse(iloc.bh);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* In data=journal mode ext4_journalled_invalidatepage() may fail to invalidate
|
|
* buffers that are attached to a page stradding i_size and are undergoing
|
|
* commit. In that case we have to wait for commit to finish and try again.
|
|
*/
|
|
static void ext4_wait_for_tail_page_commit(struct inode *inode)
|
|
{
|
|
struct page *page;
|
|
unsigned offset;
|
|
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
|
|
tid_t commit_tid = 0;
|
|
int ret;
|
|
|
|
offset = inode->i_size & (PAGE_CACHE_SIZE - 1);
|
|
/*
|
|
* All buffers in the last page remain valid? Then there's nothing to
|
|
* do. We do the check mainly to optimize the common PAGE_CACHE_SIZE ==
|
|
* blocksize case
|
|
*/
|
|
if (offset > PAGE_CACHE_SIZE - (1 << inode->i_blkbits))
|
|
return;
|
|
while (1) {
|
|
page = find_lock_page(inode->i_mapping,
|
|
inode->i_size >> PAGE_CACHE_SHIFT);
|
|
if (!page)
|
|
return;
|
|
ret = __ext4_journalled_invalidatepage(page, offset,
|
|
PAGE_CACHE_SIZE - offset);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
if (ret != -EBUSY)
|
|
return;
|
|
commit_tid = 0;
|
|
read_lock(&journal->j_state_lock);
|
|
if (journal->j_committing_transaction)
|
|
commit_tid = journal->j_committing_transaction->t_tid;
|
|
read_unlock(&journal->j_state_lock);
|
|
if (commit_tid)
|
|
jbd2_log_wait_commit(journal, commit_tid);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* ext4_setattr()
|
|
*
|
|
* Called from notify_change.
|
|
*
|
|
* We want to trap VFS attempts to truncate the file as soon as
|
|
* possible. In particular, we want to make sure that when the VFS
|
|
* shrinks i_size, we put the inode on the orphan list and modify
|
|
* i_disksize immediately, so that during the subsequent flushing of
|
|
* dirty pages and freeing of disk blocks, we can guarantee that any
|
|
* commit will leave the blocks being flushed in an unused state on
|
|
* disk. (On recovery, the inode will get truncated and the blocks will
|
|
* be freed, so we have a strong guarantee that no future commit will
|
|
* leave these blocks visible to the user.)
|
|
*
|
|
* Another thing we have to assure is that if we are in ordered mode
|
|
* and inode is still attached to the committing transaction, we must
|
|
* we start writeout of all the dirty pages which are being truncated.
|
|
* This way we are sure that all the data written in the previous
|
|
* transaction are already on disk (truncate waits for pages under
|
|
* writeback).
|
|
*
|
|
* Called with inode->i_mutex down.
|
|
*/
|
|
int ext4_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
int error, rc = 0;
|
|
int orphan = 0;
|
|
const unsigned int ia_valid = attr->ia_valid;
|
|
|
|
error = inode_change_ok(inode, attr);
|
|
if (error)
|
|
return error;
|
|
|
|
if (is_quota_modification(inode, attr))
|
|
dquot_initialize(inode);
|
|
if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
|
|
(ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
|
|
handle_t *handle;
|
|
|
|
/* (user+group)*(old+new) structure, inode write (sb,
|
|
* inode block, ? - but truncate inode update has it) */
|
|
handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
|
|
(EXT4_MAXQUOTAS_INIT_BLOCKS(inode->i_sb) +
|
|
EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)) + 3);
|
|
if (IS_ERR(handle)) {
|
|
error = PTR_ERR(handle);
|
|
goto err_out;
|
|
}
|
|
error = dquot_transfer(inode, attr);
|
|
if (error) {
|
|
ext4_journal_stop(handle);
|
|
return error;
|
|
}
|
|
/* Update corresponding info in inode so that everything is in
|
|
* one transaction */
|
|
if (attr->ia_valid & ATTR_UID)
|
|
inode->i_uid = attr->ia_uid;
|
|
if (attr->ia_valid & ATTR_GID)
|
|
inode->i_gid = attr->ia_gid;
|
|
error = ext4_mark_inode_dirty(handle, inode);
|
|
ext4_journal_stop(handle);
|
|
}
|
|
|
|
if (attr->ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
|
|
handle_t *handle;
|
|
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
|
|
if (attr->ia_size > sbi->s_bitmap_maxbytes)
|
|
return -EFBIG;
|
|
}
|
|
|
|
if (IS_I_VERSION(inode) && attr->ia_size != inode->i_size)
|
|
inode_inc_iversion(inode);
|
|
|
|
if (S_ISREG(inode->i_mode) &&
|
|
(attr->ia_size < inode->i_size)) {
|
|
if (ext4_should_order_data(inode)) {
|
|
error = ext4_begin_ordered_truncate(inode,
|
|
attr->ia_size);
|
|
if (error)
|
|
goto err_out;
|
|
}
|
|
handle = ext4_journal_start(inode, EXT4_HT_INODE, 3);
|
|
if (IS_ERR(handle)) {
|
|
error = PTR_ERR(handle);
|
|
goto err_out;
|
|
}
|
|
if (ext4_handle_valid(handle)) {
|
|
error = ext4_orphan_add(handle, inode);
|
|
orphan = 1;
|
|
}
|
|
down_write(&EXT4_I(inode)->i_data_sem);
|
|
EXT4_I(inode)->i_disksize = attr->ia_size;
|
|
rc = ext4_mark_inode_dirty(handle, inode);
|
|
if (!error)
|
|
error = rc;
|
|
/*
|
|
* We have to update i_size under i_data_sem together
|
|
* with i_disksize to avoid races with writeback code
|
|
* running ext4_wb_update_i_disksize().
|
|
*/
|
|
if (!error)
|
|
i_size_write(inode, attr->ia_size);
|
|
up_write(&EXT4_I(inode)->i_data_sem);
|
|
ext4_journal_stop(handle);
|
|
if (error) {
|
|
ext4_orphan_del(NULL, inode);
|
|
goto err_out;
|
|
}
|
|
} else
|
|
i_size_write(inode, attr->ia_size);
|
|
|
|
/*
|
|
* Blocks are going to be removed from the inode. Wait
|
|
* for dio in flight. Temporarily disable
|
|
* dioread_nolock to prevent livelock.
|
|
*/
|
|
if (orphan) {
|
|
if (!ext4_should_journal_data(inode)) {
|
|
ext4_inode_block_unlocked_dio(inode);
|
|
inode_dio_wait(inode);
|
|
ext4_inode_resume_unlocked_dio(inode);
|
|
} else
|
|
ext4_wait_for_tail_page_commit(inode);
|
|
}
|
|
/*
|
|
* Truncate pagecache after we've waited for commit
|
|
* in data=journal mode to make pages freeable.
|
|
*/
|
|
truncate_pagecache(inode, inode->i_size);
|
|
}
|
|
/*
|
|
* We want to call ext4_truncate() even if attr->ia_size ==
|
|
* inode->i_size for cases like truncation of fallocated space
|
|
*/
|
|
if (attr->ia_valid & ATTR_SIZE)
|
|
ext4_truncate(inode);
|
|
|
|
if (!rc) {
|
|
setattr_copy(inode, attr);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
/*
|
|
* If the call to ext4_truncate failed to get a transaction handle at
|
|
* all, we need to clean up the in-core orphan list manually.
|
|
*/
|
|
if (orphan && inode->i_nlink)
|
|
ext4_orphan_del(NULL, inode);
|
|
|
|
if (!rc && (ia_valid & ATTR_MODE))
|
|
rc = posix_acl_chmod(inode, inode->i_mode);
|
|
|
|
err_out:
|
|
ext4_std_error(inode->i_sb, error);
|
|
if (!error)
|
|
error = rc;
|
|
return error;
|
|
}
|
|
|
|
int ext4_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
|
struct kstat *stat)
|
|
{
|
|
struct inode *inode;
|
|
unsigned long long delalloc_blocks;
|
|
|
|
inode = dentry->d_inode;
|
|
generic_fillattr(inode, stat);
|
|
|
|
/*
|
|
* If there is inline data in the inode, the inode will normally not
|
|
* have data blocks allocated (it may have an external xattr block).
|
|
* Report at least one sector for such files, so tools like tar, rsync,
|
|
* others doen't incorrectly think the file is completely sparse.
|
|
*/
|
|
if (unlikely(ext4_has_inline_data(inode)))
|
|
stat->blocks += (stat->size + 511) >> 9;
|
|
|
|
/*
|
|
* We can't update i_blocks if the block allocation is delayed
|
|
* otherwise in the case of system crash before the real block
|
|
* allocation is done, we will have i_blocks inconsistent with
|
|
* on-disk file blocks.
|
|
* We always keep i_blocks updated together with real
|
|
* allocation. But to not confuse with user, stat
|
|
* will return the blocks that include the delayed allocation
|
|
* blocks for this file.
|
|
*/
|
|
delalloc_blocks = EXT4_C2B(EXT4_SB(inode->i_sb),
|
|
EXT4_I(inode)->i_reserved_data_blocks);
|
|
stat->blocks += delalloc_blocks << (inode->i_sb->s_blocksize_bits - 9);
|
|
return 0;
|
|
}
|
|
|
|
static int ext4_index_trans_blocks(struct inode *inode, int lblocks,
|
|
int pextents)
|
|
{
|
|
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
|
|
return ext4_ind_trans_blocks(inode, lblocks);
|
|
return ext4_ext_index_trans_blocks(inode, pextents);
|
|
}
|
|
|
|
/*
|
|
* Account for index blocks, block groups bitmaps and block group
|
|
* descriptor blocks if modify datablocks and index blocks
|
|
* worse case, the indexs blocks spread over different block groups
|
|
*
|
|
* If datablocks are discontiguous, they are possible to spread over
|
|
* different block groups too. If they are contiguous, with flexbg,
|
|
* they could still across block group boundary.
|
|
*
|
|
* Also account for superblock, inode, quota and xattr blocks
|
|
*/
|
|
static int ext4_meta_trans_blocks(struct inode *inode, int lblocks,
|
|
int pextents)
|
|
{
|
|
ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb);
|
|
int gdpblocks;
|
|
int idxblocks;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* How many index blocks need to touch to map @lblocks logical blocks
|
|
* to @pextents physical extents?
|
|
*/
|
|
idxblocks = ext4_index_trans_blocks(inode, lblocks, pextents);
|
|
|
|
ret = idxblocks;
|
|
|
|
/*
|
|
* Now let's see how many group bitmaps and group descriptors need
|
|
* to account
|
|
*/
|
|
groups = idxblocks + pextents;
|
|
gdpblocks = groups;
|
|
if (groups > ngroups)
|
|
groups = ngroups;
|
|
if (groups > EXT4_SB(inode->i_sb)->s_gdb_count)
|
|
gdpblocks = EXT4_SB(inode->i_sb)->s_gdb_count;
|
|
|
|
/* bitmaps and block group descriptor blocks */
|
|
ret += groups + gdpblocks;
|
|
|
|
/* Blocks for super block, inode, quota and xattr blocks */
|
|
ret += EXT4_META_TRANS_BLOCKS(inode->i_sb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Calculate the total number of credits to reserve to fit
|
|
* the modification of a single pages into a single transaction,
|
|
* which may include multiple chunks of block allocations.
|
|
*
|
|
* This could be called via ext4_write_begin()
|
|
*
|
|
* We need to consider the worse case, when
|
|
* one new block per extent.
|
|
*/
|
|
int ext4_writepage_trans_blocks(struct inode *inode)
|
|
{
|
|
int bpp = ext4_journal_blocks_per_page(inode);
|
|
int ret;
|
|
|
|
ret = ext4_meta_trans_blocks(inode, bpp, bpp);
|
|
|
|
/* Account for data blocks for journalled mode */
|
|
if (ext4_should_journal_data(inode))
|
|
ret += bpp;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Calculate the journal credits for a chunk of data modification.
|
|
*
|
|
* This is called from DIO, fallocate or whoever calling
|
|
* ext4_map_blocks() to map/allocate a chunk of contiguous disk blocks.
|
|
*
|
|
* journal buffers for data blocks are not included here, as DIO
|
|
* and fallocate do no need to journal data buffers.
|
|
*/
|
|
int ext4_chunk_trans_blocks(struct inode *inode, int nrblocks)
|
|
{
|
|
return ext4_meta_trans_blocks(inode, nrblocks, 1);
|
|
}
|
|
|
|
/*
|
|
* The caller must have previously called ext4_reserve_inode_write().
|
|
* Give this, we know that the caller already has write access to iloc->bh.
|
|
*/
|
|
int ext4_mark_iloc_dirty(handle_t *handle,
|
|
struct inode *inode, struct ext4_iloc *iloc)
|
|
{
|
|
int err = 0;
|
|
|
|
if (IS_I_VERSION(inode))
|
|
inode_inc_iversion(inode);
|
|
|
|
/* the do_update_inode consumes one bh->b_count */
|
|
get_bh(iloc->bh);
|
|
|
|
/* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
|
|
err = ext4_do_update_inode(handle, inode, iloc);
|
|
put_bh(iloc->bh);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* On success, We end up with an outstanding reference count against
|
|
* iloc->bh. This _must_ be cleaned up later.
|
|
*/
|
|
|
|
int
|
|
ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
|
|
struct ext4_iloc *iloc)
|
|
{
|
|
int err;
|
|
|
|
err = ext4_get_inode_loc(inode, iloc);
|
|
if (!err) {
|
|
BUFFER_TRACE(iloc->bh, "get_write_access");
|
|
err = ext4_journal_get_write_access(handle, iloc->bh);
|
|
if (err) {
|
|
brelse(iloc->bh);
|
|
iloc->bh = NULL;
|
|
}
|
|
}
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Expand an inode by new_extra_isize bytes.
|
|
* Returns 0 on success or negative error number on failure.
|
|
*/
|
|
static int ext4_expand_extra_isize(struct inode *inode,
|
|
unsigned int new_extra_isize,
|
|
struct ext4_iloc iloc,
|
|
handle_t *handle)
|
|
{
|
|
struct ext4_inode *raw_inode;
|
|
struct ext4_xattr_ibody_header *header;
|
|
|
|
if (EXT4_I(inode)->i_extra_isize >= new_extra_isize)
|
|
return 0;
|
|
|
|
raw_inode = ext4_raw_inode(&iloc);
|
|
|
|
header = IHDR(inode, raw_inode);
|
|
|
|
/* No extended attributes present */
|
|
if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR) ||
|
|
header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) {
|
|
memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0,
|
|
new_extra_isize);
|
|
EXT4_I(inode)->i_extra_isize = new_extra_isize;
|
|
return 0;
|
|
}
|
|
|
|
/* try to expand with EAs present */
|
|
return ext4_expand_extra_isize_ea(inode, new_extra_isize,
|
|
raw_inode, handle);
|
|
}
|
|
|
|
/*
|
|
* What we do here is to mark the in-core inode as clean with respect to inode
|
|
* dirtiness (it may still be data-dirty).
|
|
* This means that the in-core inode may be reaped by prune_icache
|
|
* without having to perform any I/O. This is a very good thing,
|
|
* because *any* task may call prune_icache - even ones which
|
|
* have a transaction open against a different journal.
|
|
*
|
|
* Is this cheating? Not really. Sure, we haven't written the
|
|
* inode out, but prune_icache isn't a user-visible syncing function.
|
|
* Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
|
|
* we start and wait on commits.
|
|
*/
|
|
int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
|
|
static unsigned int mnt_count;
|
|
int err, ret;
|
|
|
|
might_sleep();
|
|
trace_ext4_mark_inode_dirty(inode, _RET_IP_);
|
|
err = ext4_reserve_inode_write(handle, inode, &iloc);
|
|
if (ext4_handle_valid(handle) &&
|
|
EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize &&
|
|
!ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
|
|
/*
|
|
* We need extra buffer credits since we may write into EA block
|
|
* with this same handle. If journal_extend fails, then it will
|
|
* only result in a minor loss of functionality for that inode.
|
|
* If this is felt to be critical, then e2fsck should be run to
|
|
* force a large enough s_min_extra_isize.
|
|
*/
|
|
if ((jbd2_journal_extend(handle,
|
|
EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) {
|
|
ret = ext4_expand_extra_isize(inode,
|
|
sbi->s_want_extra_isize,
|
|
iloc, handle);
|
|
if (ret) {
|
|
ext4_set_inode_state(inode,
|
|
EXT4_STATE_NO_EXPAND);
|
|
if (mnt_count !=
|
|
le16_to_cpu(sbi->s_es->s_mnt_count)) {
|
|
ext4_warning(inode->i_sb,
|
|
"Unable to expand inode %lu. Delete"
|
|
" some EAs or run e2fsck.",
|
|
inode->i_ino);
|
|
mnt_count =
|
|
le16_to_cpu(sbi->s_es->s_mnt_count);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (!err)
|
|
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* ext4_dirty_inode() is called from __mark_inode_dirty()
|
|
*
|
|
* We're really interested in the case where a file is being extended.
|
|
* i_size has been changed by generic_commit_write() and we thus need
|
|
* to include the updated inode in the current transaction.
|
|
*
|
|
* Also, dquot_alloc_block() will always dirty the inode when blocks
|
|
* are allocated to the file.
|
|
*
|
|
* If the inode is marked synchronous, we don't honour that here - doing
|
|
* so would cause a commit on atime updates, which we don't bother doing.
|
|
* We handle synchronous inodes at the highest possible level.
|
|
*/
|
|
void ext4_dirty_inode(struct inode *inode, int flags)
|
|
{
|
|
handle_t *handle;
|
|
|
|
handle = ext4_journal_start(inode, EXT4_HT_INODE, 2);
|
|
if (IS_ERR(handle))
|
|
goto out;
|
|
|
|
ext4_mark_inode_dirty(handle, inode);
|
|
|
|
ext4_journal_stop(handle);
|
|
out:
|
|
return;
|
|
}
|
|
|
|
#if 0
|
|
/*
|
|
* Bind an inode's backing buffer_head into this transaction, to prevent
|
|
* it from being flushed to disk early. Unlike
|
|
* ext4_reserve_inode_write, this leaves behind no bh reference and
|
|
* returns no iloc structure, so the caller needs to repeat the iloc
|
|
* lookup to mark the inode dirty later.
|
|
*/
|
|
static int ext4_pin_inode(handle_t *handle, struct inode *inode)
|
|
{
|
|
struct ext4_iloc iloc;
|
|
|
|
int err = 0;
|
|
if (handle) {
|
|
err = ext4_get_inode_loc(inode, &iloc);
|
|
if (!err) {
|
|
BUFFER_TRACE(iloc.bh, "get_write_access");
|
|
err = jbd2_journal_get_write_access(handle, iloc.bh);
|
|
if (!err)
|
|
err = ext4_handle_dirty_metadata(handle,
|
|
NULL,
|
|
iloc.bh);
|
|
brelse(iloc.bh);
|
|
}
|
|
}
|
|
ext4_std_error(inode->i_sb, err);
|
|
return err;
|
|
}
|
|
#endif
|
|
|
|
int ext4_change_inode_journal_flag(struct inode *inode, int val)
|
|
{
|
|
journal_t *journal;
|
|
handle_t *handle;
|
|
int err;
|
|
|
|
/*
|
|
* We have to be very careful here: changing a data block's
|
|
* journaling status dynamically is dangerous. If we write a
|
|
* data block to the journal, change the status and then delete
|
|
* that block, we risk forgetting to revoke the old log record
|
|
* from the journal and so a subsequent replay can corrupt data.
|
|
* So, first we make sure that the journal is empty and that
|
|
* nobody is changing anything.
|
|
*/
|
|
|
|
journal = EXT4_JOURNAL(inode);
|
|
if (!journal)
|
|
return 0;
|
|
if (is_journal_aborted(journal))
|
|
return -EROFS;
|
|
/* We have to allocate physical blocks for delalloc blocks
|
|
* before flushing journal. otherwise delalloc blocks can not
|
|
* be allocated any more. even more truncate on delalloc blocks
|
|
* could trigger BUG by flushing delalloc blocks in journal.
|
|
* There is no delalloc block in non-journal data mode.
|
|
*/
|
|
if (val && test_opt(inode->i_sb, DELALLOC)) {
|
|
err = ext4_alloc_da_blocks(inode);
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
|
|
/* Wait for all existing dio workers */
|
|
ext4_inode_block_unlocked_dio(inode);
|
|
inode_dio_wait(inode);
|
|
|
|
jbd2_journal_lock_updates(journal);
|
|
|
|
/*
|
|
* OK, there are no updates running now, and all cached data is
|
|
* synced to disk. We are now in a completely consistent state
|
|
* which doesn't have anything in the journal, and we know that
|
|
* no filesystem updates are running, so it is safe to modify
|
|
* the inode's in-core data-journaling state flag now.
|
|
*/
|
|
|
|
if (val)
|
|
ext4_set_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
|
|
else {
|
|
jbd2_journal_flush(journal);
|
|
ext4_clear_inode_flag(inode, EXT4_INODE_JOURNAL_DATA);
|
|
}
|
|
ext4_set_aops(inode);
|
|
|
|
jbd2_journal_unlock_updates(journal);
|
|
ext4_inode_resume_unlocked_dio(inode);
|
|
|
|
/* Finally we can mark the inode as dirty. */
|
|
|
|
handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
|
|
if (IS_ERR(handle))
|
|
return PTR_ERR(handle);
|
|
|
|
err = ext4_mark_inode_dirty(handle, inode);
|
|
ext4_handle_sync(handle);
|
|
ext4_journal_stop(handle);
|
|
ext4_std_error(inode->i_sb, err);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int ext4_bh_unmapped(handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
return !buffer_mapped(bh);
|
|
}
|
|
|
|
int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
|
|
{
|
|
struct page *page = vmf->page;
|
|
loff_t size;
|
|
unsigned long len;
|
|
int ret;
|
|
struct file *file = vma->vm_file;
|
|
struct inode *inode = file_inode(file);
|
|
struct address_space *mapping = inode->i_mapping;
|
|
handle_t *handle;
|
|
get_block_t *get_block;
|
|
int retries = 0;
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
file_update_time(vma->vm_file);
|
|
/* Delalloc case is easy... */
|
|
if (test_opt(inode->i_sb, DELALLOC) &&
|
|
!ext4_should_journal_data(inode) &&
|
|
!ext4_nonda_switch(inode->i_sb)) {
|
|
do {
|
|
ret = __block_page_mkwrite(vma, vmf,
|
|
ext4_da_get_block_prep);
|
|
} while (ret == -ENOSPC &&
|
|
ext4_should_retry_alloc(inode->i_sb, &retries));
|
|
goto out_ret;
|
|
}
|
|
|
|
lock_page(page);
|
|
size = i_size_read(inode);
|
|
/* Page got truncated from under us? */
|
|
if (page->mapping != mapping || page_offset(page) > size) {
|
|
unlock_page(page);
|
|
ret = VM_FAULT_NOPAGE;
|
|
goto out;
|
|
}
|
|
|
|
if (page->index == size >> PAGE_CACHE_SHIFT)
|
|
len = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
len = PAGE_CACHE_SIZE;
|
|
/*
|
|
* Return if we have all the buffers mapped. This avoids the need to do
|
|
* journal_start/journal_stop which can block and take a long time
|
|
*/
|
|
if (page_has_buffers(page)) {
|
|
if (!ext4_walk_page_buffers(NULL, page_buffers(page),
|
|
0, len, NULL,
|
|
ext4_bh_unmapped)) {
|
|
/* Wait so that we don't change page under IO */
|
|
wait_for_stable_page(page);
|
|
ret = VM_FAULT_LOCKED;
|
|
goto out;
|
|
}
|
|
}
|
|
unlock_page(page);
|
|
/* OK, we need to fill the hole... */
|
|
if (ext4_should_dioread_nolock(inode))
|
|
get_block = ext4_get_block_write;
|
|
else
|
|
get_block = ext4_get_block;
|
|
retry_alloc:
|
|
handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE,
|
|
ext4_writepage_trans_blocks(inode));
|
|
if (IS_ERR(handle)) {
|
|
ret = VM_FAULT_SIGBUS;
|
|
goto out;
|
|
}
|
|
ret = __block_page_mkwrite(vma, vmf, get_block);
|
|
if (!ret && ext4_should_journal_data(inode)) {
|
|
if (ext4_walk_page_buffers(handle, page_buffers(page), 0,
|
|
PAGE_CACHE_SIZE, NULL, do_journal_get_write_access)) {
|
|
unlock_page(page);
|
|
ret = VM_FAULT_SIGBUS;
|
|
ext4_journal_stop(handle);
|
|
goto out;
|
|
}
|
|
ext4_set_inode_state(inode, EXT4_STATE_JDATA);
|
|
}
|
|
ext4_journal_stop(handle);
|
|
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
|
|
goto retry_alloc;
|
|
out_ret:
|
|
ret = block_page_mkwrite_return(ret);
|
|
out:
|
|
sb_end_pagefault(inode->i_sb);
|
|
return ret;
|
|
}
|