335 lines
8.1 KiB
C
335 lines
8.1 KiB
C
/*
|
|
* Copyright (c) 2014 Christoph Hellwig.
|
|
*/
|
|
#include "xfs.h"
|
|
#include "xfs_format.h"
|
|
#include "xfs_log_format.h"
|
|
#include "xfs_trans_resv.h"
|
|
#include "xfs_sb.h"
|
|
#include "xfs_mount.h"
|
|
#include "xfs_inode.h"
|
|
#include "xfs_trans.h"
|
|
#include "xfs_log.h"
|
|
#include "xfs_bmap.h"
|
|
#include "xfs_bmap_util.h"
|
|
#include "xfs_error.h"
|
|
#include "xfs_iomap.h"
|
|
#include "xfs_shared.h"
|
|
#include "xfs_bit.h"
|
|
#include "xfs_pnfs.h"
|
|
|
|
/*
|
|
* Ensure that we do not have any outstanding pNFS layouts that can be used by
|
|
* clients to directly read from or write to this inode. This must be called
|
|
* before every operation that can remove blocks from the extent map.
|
|
* Additionally we call it during the write operation, where aren't concerned
|
|
* about exposing unallocated blocks but just want to provide basic
|
|
* synchronization between a local writer and pNFS clients. mmap writes would
|
|
* also benefit from this sort of synchronization, but due to the tricky locking
|
|
* rules in the page fault path we don't bother.
|
|
*/
|
|
int
|
|
xfs_break_layouts(
|
|
struct inode *inode,
|
|
uint *iolock,
|
|
bool with_imutex)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
int error;
|
|
|
|
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL));
|
|
|
|
while ((error = break_layout(inode, false) == -EWOULDBLOCK)) {
|
|
xfs_iunlock(ip, *iolock);
|
|
if (with_imutex && (*iolock & XFS_IOLOCK_EXCL))
|
|
inode_unlock(inode);
|
|
error = break_layout(inode, true);
|
|
*iolock = XFS_IOLOCK_EXCL;
|
|
if (with_imutex)
|
|
inode_lock(inode);
|
|
xfs_ilock(ip, *iolock);
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Get a unique ID including its location so that the client can identify
|
|
* the exported device.
|
|
*/
|
|
int
|
|
xfs_fs_get_uuid(
|
|
struct super_block *sb,
|
|
u8 *buf,
|
|
u32 *len,
|
|
u64 *offset)
|
|
{
|
|
struct xfs_mount *mp = XFS_M(sb);
|
|
|
|
printk_once(KERN_NOTICE
|
|
"XFS (%s): using experimental pNFS feature, use at your own risk!\n",
|
|
mp->m_fsname);
|
|
|
|
if (*len < sizeof(uuid_t))
|
|
return -EINVAL;
|
|
|
|
memcpy(buf, &mp->m_sb.sb_uuid, sizeof(uuid_t));
|
|
*len = sizeof(uuid_t);
|
|
*offset = offsetof(struct xfs_dsb, sb_uuid);
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
xfs_bmbt_to_iomap(
|
|
struct xfs_inode *ip,
|
|
struct iomap *iomap,
|
|
struct xfs_bmbt_irec *imap)
|
|
{
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
|
|
if (imap->br_startblock == HOLESTARTBLOCK) {
|
|
iomap->blkno = IOMAP_NULL_BLOCK;
|
|
iomap->type = IOMAP_HOLE;
|
|
} else if (imap->br_startblock == DELAYSTARTBLOCK) {
|
|
iomap->blkno = IOMAP_NULL_BLOCK;
|
|
iomap->type = IOMAP_DELALLOC;
|
|
} else {
|
|
iomap->blkno =
|
|
XFS_FSB_TO_DADDR(ip->i_mount, imap->br_startblock);
|
|
if (imap->br_state == XFS_EXT_UNWRITTEN)
|
|
iomap->type = IOMAP_UNWRITTEN;
|
|
else
|
|
iomap->type = IOMAP_MAPPED;
|
|
}
|
|
iomap->offset = XFS_FSB_TO_B(mp, imap->br_startoff);
|
|
iomap->length = XFS_FSB_TO_B(mp, imap->br_blockcount);
|
|
}
|
|
|
|
/*
|
|
* Get a layout for the pNFS client.
|
|
*/
|
|
int
|
|
xfs_fs_map_blocks(
|
|
struct inode *inode,
|
|
loff_t offset,
|
|
u64 length,
|
|
struct iomap *iomap,
|
|
bool write,
|
|
u32 *device_generation)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
struct xfs_bmbt_irec imap;
|
|
xfs_fileoff_t offset_fsb, end_fsb;
|
|
loff_t limit;
|
|
int bmapi_flags = XFS_BMAPI_ENTIRE;
|
|
int nimaps = 1;
|
|
uint lock_flags;
|
|
int error = 0;
|
|
|
|
if (XFS_FORCED_SHUTDOWN(mp))
|
|
return -EIO;
|
|
|
|
/*
|
|
* We can't export inodes residing on the realtime device. The realtime
|
|
* device doesn't have a UUID to identify it, so the client has no way
|
|
* to find it.
|
|
*/
|
|
if (XFS_IS_REALTIME_INODE(ip))
|
|
return -ENXIO;
|
|
|
|
/*
|
|
* Lock out any other I/O before we flush and invalidate the pagecache,
|
|
* and then hand out a layout to the remote system. This is very
|
|
* similar to direct I/O, except that the synchronization is much more
|
|
* complicated. See the comment near xfs_break_layouts for a detailed
|
|
* explanation.
|
|
*/
|
|
xfs_ilock(ip, XFS_IOLOCK_EXCL);
|
|
|
|
error = -EINVAL;
|
|
limit = mp->m_super->s_maxbytes;
|
|
if (!write)
|
|
limit = max(limit, round_up(i_size_read(inode),
|
|
inode->i_sb->s_blocksize));
|
|
if (offset > limit)
|
|
goto out_unlock;
|
|
if (offset > limit - length)
|
|
length = limit - offset;
|
|
|
|
error = filemap_write_and_wait(inode->i_mapping);
|
|
if (error)
|
|
goto out_unlock;
|
|
error = invalidate_inode_pages2(inode->i_mapping);
|
|
if (WARN_ON_ONCE(error))
|
|
return error;
|
|
|
|
end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + length);
|
|
offset_fsb = XFS_B_TO_FSBT(mp, offset);
|
|
|
|
lock_flags = xfs_ilock_data_map_shared(ip);
|
|
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb,
|
|
&imap, &nimaps, bmapi_flags);
|
|
xfs_iunlock(ip, lock_flags);
|
|
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
if (write) {
|
|
enum xfs_prealloc_flags flags = 0;
|
|
|
|
ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
|
|
|
|
if (!nimaps || imap.br_startblock == HOLESTARTBLOCK) {
|
|
/*
|
|
* xfs_iomap_write_direct() expects to take ownership of
|
|
* the shared ilock.
|
|
*/
|
|
xfs_ilock(ip, XFS_ILOCK_SHARED);
|
|
error = xfs_iomap_write_direct(ip, offset, length,
|
|
&imap, nimaps);
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
/*
|
|
* Ensure the next transaction is committed
|
|
* synchronously so that the blocks allocated and
|
|
* handed out to the client are guaranteed to be
|
|
* present even after a server crash.
|
|
*/
|
|
flags |= XFS_PREALLOC_SET | XFS_PREALLOC_SYNC;
|
|
}
|
|
|
|
error = xfs_update_prealloc_flags(ip, flags);
|
|
if (error)
|
|
goto out_unlock;
|
|
}
|
|
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
|
|
|
|
xfs_bmbt_to_iomap(ip, iomap, &imap);
|
|
*device_generation = mp->m_generation;
|
|
return error;
|
|
out_unlock:
|
|
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Ensure the size update falls into a valid allocated block.
|
|
*/
|
|
static int
|
|
xfs_pnfs_validate_isize(
|
|
struct xfs_inode *ip,
|
|
xfs_off_t isize)
|
|
{
|
|
struct xfs_bmbt_irec imap;
|
|
int nimaps = 1;
|
|
int error = 0;
|
|
|
|
xfs_ilock(ip, XFS_ILOCK_SHARED);
|
|
error = xfs_bmapi_read(ip, XFS_B_TO_FSBT(ip->i_mount, isize - 1), 1,
|
|
&imap, &nimaps, 0);
|
|
xfs_iunlock(ip, XFS_ILOCK_SHARED);
|
|
if (error)
|
|
return error;
|
|
|
|
if (imap.br_startblock == HOLESTARTBLOCK ||
|
|
imap.br_startblock == DELAYSTARTBLOCK ||
|
|
imap.br_state == XFS_EXT_UNWRITTEN)
|
|
return -EIO;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Make sure the blocks described by maps are stable on disk. This includes
|
|
* converting any unwritten extents, flushing the disk cache and updating the
|
|
* time stamps.
|
|
*
|
|
* Note that we rely on the caller to always send us a timestamp update so that
|
|
* we always commit a transaction here. If that stops being true we will have
|
|
* to manually flush the cache here similar to what the fsync code path does
|
|
* for datasyncs on files that have no dirty metadata.
|
|
*/
|
|
int
|
|
xfs_fs_commit_blocks(
|
|
struct inode *inode,
|
|
struct iomap *maps,
|
|
int nr_maps,
|
|
struct iattr *iattr)
|
|
{
|
|
struct xfs_inode *ip = XFS_I(inode);
|
|
struct xfs_mount *mp = ip->i_mount;
|
|
struct xfs_trans *tp;
|
|
bool update_isize = false;
|
|
int error, i;
|
|
loff_t size;
|
|
|
|
ASSERT(iattr->ia_valid & (ATTR_ATIME|ATTR_CTIME|ATTR_MTIME));
|
|
|
|
xfs_ilock(ip, XFS_IOLOCK_EXCL);
|
|
|
|
size = i_size_read(inode);
|
|
if ((iattr->ia_valid & ATTR_SIZE) && iattr->ia_size > size) {
|
|
update_isize = true;
|
|
size = iattr->ia_size;
|
|
}
|
|
|
|
for (i = 0; i < nr_maps; i++) {
|
|
u64 start, length, end;
|
|
|
|
start = maps[i].offset;
|
|
if (start > size)
|
|
continue;
|
|
|
|
end = start + maps[i].length;
|
|
if (end > size)
|
|
end = size;
|
|
|
|
length = end - start;
|
|
if (!length)
|
|
continue;
|
|
|
|
/*
|
|
* Make sure reads through the pagecache see the new data.
|
|
*/
|
|
error = invalidate_inode_pages2_range(inode->i_mapping,
|
|
start >> PAGE_SHIFT,
|
|
(end - 1) >> PAGE_SHIFT);
|
|
WARN_ON_ONCE(error);
|
|
|
|
error = xfs_iomap_write_unwritten(ip, start, length);
|
|
if (error)
|
|
goto out_drop_iolock;
|
|
}
|
|
|
|
if (update_isize) {
|
|
error = xfs_pnfs_validate_isize(ip, size);
|
|
if (error)
|
|
goto out_drop_iolock;
|
|
}
|
|
|
|
tp = xfs_trans_alloc(mp, XFS_TRANS_SETATTR_NOT_SIZE);
|
|
error = xfs_trans_reserve(tp, &M_RES(mp)->tr_ichange, 0, 0);
|
|
if (error) {
|
|
xfs_trans_cancel(tp);
|
|
goto out_drop_iolock;
|
|
}
|
|
|
|
xfs_ilock(ip, XFS_ILOCK_EXCL);
|
|
xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
|
|
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
|
|
|
|
xfs_setattr_time(ip, iattr);
|
|
if (update_isize) {
|
|
i_size_write(inode, iattr->ia_size);
|
|
ip->i_d.di_size = iattr->ia_size;
|
|
}
|
|
|
|
xfs_trans_set_sync(tp);
|
|
error = xfs_trans_commit(tp);
|
|
|
|
out_drop_iolock:
|
|
xfs_iunlock(ip, XFS_IOLOCK_EXCL);
|
|
return error;
|
|
}
|