Btrfs: split up super.c
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason
David Woodhouse
parent
5276aedab0
commit
39279cc3d2
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@ -4,7 +4,7 @@ ifneq ($(KERNELRELEASE),)
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obj-m := btrfs.o
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btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
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hash.o file-item.o inode-item.o inode-map.o disk-io.o \
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transaction.o bit-radix.o
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transaction.o bit-radix.o inode.o file.o
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#btrfs-y := ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \
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# root-tree.o dir-item.o hash.o file-item.o inode-item.o \
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@ -16,7 +16,7 @@ else
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KERNELDIR := /lib/modules/`uname -r`/build
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all::
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$(MAKE) C=1 -C $(KERNELDIR) M=`pwd` modules
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$(MAKE) -C $(KERNELDIR) M=`pwd` modules
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clean::
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rm *.o btrfs.ko
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endif
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@ -1,3 +1,4 @@
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* fix printk warnings
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* cleanup, add more error checking, get rid of BUG_ONs
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* Fix ENOSPC handling
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* Make allocator smarter
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@ -1123,5 +1123,28 @@ struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
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int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct btrfs_path *path,
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u64 isize);
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/* super.c */
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/* inode.c */
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void btrfs_delete_inode(struct inode *inode);
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void btrfs_read_locked_inode(struct inode *inode);
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int btrfs_write_inode(struct inode *inode, int wait);
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void btrfs_dirty_inode(struct inode *inode);
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struct inode *btrfs_alloc_inode(struct super_block *sb);
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void btrfs_destroy_inode(struct inode *inode);
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int btrfs_init_cachep(void);
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void btrfs_destroy_cachep(void);
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int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
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unsigned long arg);
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long btrfs_compat_ioctl(struct file *file, unsigned int cmd,
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unsigned long arg);
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struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
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struct btrfs_root *root);
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int btrfs_commit_write(struct file *file, struct page *page,
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unsigned from, unsigned to);
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int btrfs_get_block(struct inode *inode, sector_t iblock,
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struct buffer_head *result, int create);
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/* file.c */
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extern struct file_operations btrfs_file_operations;
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int btrfs_drop_extents(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct inode *inode,
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u64 start, u64 end, u64 *hint_block);
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#endif
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@ -22,7 +22,7 @@ static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
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if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) {
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printk(KERN_CRIT "bh_blocknr(buf) is %Lu, header is %Lu\n",
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bh_blocknr(buf), btrfs_header_blocknr(&node->header));
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BUG();
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return 1;
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}
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return 0;
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}
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@ -253,7 +253,7 @@ uptodate:
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set_buffer_checked(bh);
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}
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if (check_tree_block(root, bh))
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BUG();
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goto fail;
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return bh;
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fail:
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brelse(bh);
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@ -398,8 +398,13 @@ struct btrfs_root *open_ctree(struct super_block *sb)
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struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
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GFP_NOFS);
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int ret;
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int err = -EIO;
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struct btrfs_super_block *disk_super;
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if (!extent_root || !tree_root || !fs_info) {
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err = -ENOMEM;
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goto fail;
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}
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init_bit_radix(&fs_info->pinned_radix);
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init_bit_radix(&fs_info->pending_del_radix);
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init_bit_radix(&fs_info->extent_map_radix);
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@ -431,9 +436,11 @@ struct btrfs_root *open_ctree(struct super_block *sb)
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mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
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fs_info->hash_tfm = crypto_alloc_hash("crc32c", 0, CRYPTO_ALG_ASYNC);
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spin_lock_init(&fs_info->hash_lock);
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if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) {
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printk("failed to allocate digest hash\n");
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return NULL;
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printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
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err = -ENOMEM;
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goto fail_iput;
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}
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mutex_init(&fs_info->trans_mutex);
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mutex_init(&fs_info->fs_mutex);
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@ -446,30 +453,53 @@ struct btrfs_root *open_ctree(struct super_block *sb)
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sb->s_blocksize);
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if (!fs_info->sb_buffer)
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return NULL;
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goto fail_iput;
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disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
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if (!btrfs_super_root(disk_super))
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return NULL;
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goto fail_sb_buffer;
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i_size_write(fs_info->btree_inode,
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btrfs_super_total_blocks(disk_super) <<
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fs_info->btree_inode->i_blkbits);
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fs_info->disk_super = disk_super;
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if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
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sizeof(disk_super->magic))) {
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printk("btrfs: valid FS not found on %s\n", sb->s_id);
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goto fail_sb_buffer;
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}
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tree_root->node = read_tree_block(tree_root,
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btrfs_super_root(disk_super));
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BUG_ON(!tree_root->node);
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if (!tree_root->node)
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goto fail_sb_buffer;
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mutex_lock(&fs_info->fs_mutex);
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ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
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BTRFS_EXTENT_TREE_OBJECTID, extent_root);
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BUG_ON(ret);
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if (ret) {
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mutex_unlock(&fs_info->fs_mutex);
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goto fail_tree_root;
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}
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btrfs_read_block_groups(extent_root);
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fs_info->generation = btrfs_super_generation(disk_super) + 1;
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mutex_unlock(&fs_info->fs_mutex);
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return tree_root;
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fail_tree_root:
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btrfs_block_release(tree_root, tree_root->node);
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fail_sb_buffer:
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btrfs_block_release(tree_root, fs_info->sb_buffer);
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fail_iput:
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iput(fs_info->btree_inode);
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fail:
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kfree(extent_root);
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kfree(tree_root);
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kfree(fs_info);
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return ERR_PTR(err);
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}
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int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
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@ -0,0 +1,783 @@
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#include <linux/module.h>
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#include <linux/buffer_head.h>
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/smp_lock.h>
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#include <linux/backing-dev.h>
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#include <linux/mpage.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "ioctl.h"
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#include "print-tree.h"
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static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
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struct page **prepared_pages,
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const char __user * buf)
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{
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long page_fault = 0;
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int i;
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int offset = pos & (PAGE_CACHE_SIZE - 1);
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for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
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size_t count = min_t(size_t,
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PAGE_CACHE_SIZE - offset, write_bytes);
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struct page *page = prepared_pages[i];
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fault_in_pages_readable(buf, count);
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/* Copy data from userspace to the current page */
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kmap(page);
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page_fault = __copy_from_user(page_address(page) + offset,
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buf, count);
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/* Flush processor's dcache for this page */
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flush_dcache_page(page);
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kunmap(page);
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buf += count;
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write_bytes -= count;
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if (page_fault)
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break;
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}
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return page_fault ? -EFAULT : 0;
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}
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static void btrfs_drop_pages(struct page **pages, size_t num_pages)
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{
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size_t i;
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for (i = 0; i < num_pages; i++) {
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if (!pages[i])
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break;
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unlock_page(pages[i]);
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mark_page_accessed(pages[i]);
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page_cache_release(pages[i]);
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}
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}
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static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct file *file,
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struct page **pages,
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size_t num_pages,
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loff_t pos,
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size_t write_bytes)
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{
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int i;
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int offset;
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int err = 0;
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int ret;
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int this_write;
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struct inode *inode = file->f_path.dentry->d_inode;
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struct buffer_head *bh;
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struct btrfs_file_extent_item *ei;
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for (i = 0; i < num_pages; i++) {
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offset = pos & (PAGE_CACHE_SIZE -1);
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this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
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/* FIXME, one block at a time */
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mutex_lock(&root->fs_info->fs_mutex);
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trans = btrfs_start_transaction(root, 1);
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btrfs_set_trans_block_group(trans, inode);
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bh = page_buffers(pages[i]);
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if (buffer_mapped(bh) && bh->b_blocknr == 0) {
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struct btrfs_key key;
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struct btrfs_path *path;
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char *ptr;
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u32 datasize;
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/* create an inline extent, and copy the data in */
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path = btrfs_alloc_path();
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BUG_ON(!path);
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key.objectid = inode->i_ino;
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key.offset = pages[i]->index << PAGE_CACHE_SHIFT;
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key.flags = 0;
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btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
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BUG_ON(write_bytes >= PAGE_CACHE_SIZE);
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datasize = offset +
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btrfs_file_extent_calc_inline_size(write_bytes);
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ret = btrfs_insert_empty_item(trans, root, path, &key,
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datasize);
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BUG_ON(ret);
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ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
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path->slots[0], struct btrfs_file_extent_item);
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btrfs_set_file_extent_generation(ei, trans->transid);
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btrfs_set_file_extent_type(ei,
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BTRFS_FILE_EXTENT_INLINE);
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ptr = btrfs_file_extent_inline_start(ei);
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btrfs_memcpy(root, path->nodes[0]->b_data,
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ptr, bh->b_data, offset + write_bytes);
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mark_buffer_dirty(path->nodes[0]);
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btrfs_free_path(path);
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} else if (buffer_mapped(bh)) {
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/* csum the file data */
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btrfs_csum_file_block(trans, root, inode->i_ino,
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pages[i]->index << PAGE_CACHE_SHIFT,
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kmap(pages[i]), PAGE_CACHE_SIZE);
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kunmap(pages[i]);
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}
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SetPageChecked(pages[i]);
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ret = btrfs_end_transaction(trans, root);
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BUG_ON(ret);
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mutex_unlock(&root->fs_info->fs_mutex);
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ret = btrfs_commit_write(file, pages[i], offset,
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offset + this_write);
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pos += this_write;
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if (ret) {
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err = ret;
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goto failed;
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}
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WARN_ON(this_write > write_bytes);
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write_bytes -= this_write;
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}
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failed:
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return err;
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}
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/*
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* this is very complex, but the basic idea is to drop all extents
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* in the range start - end. hint_block is filled in with a block number
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* that would be a good hint to the block allocator for this file.
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*
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* If an extent intersects the range but is not entirely inside the range
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* it is either truncated or split. Anything entirely inside the range
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* is deleted from the tree.
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*/
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int btrfs_drop_extents(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct inode *inode,
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u64 start, u64 end, u64 *hint_block)
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{
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int ret;
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struct btrfs_key key;
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struct btrfs_leaf *leaf;
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int slot;
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struct btrfs_file_extent_item *extent;
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u64 extent_end = 0;
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int keep;
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struct btrfs_file_extent_item old;
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struct btrfs_path *path;
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u64 search_start = start;
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int bookend;
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int found_type;
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int found_extent;
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int found_inline;
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path = btrfs_alloc_path();
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if (!path)
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return -ENOMEM;
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while(1) {
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btrfs_release_path(root, path);
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ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
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search_start, -1);
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if (ret < 0)
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goto out;
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if (ret > 0) {
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if (path->slots[0] == 0) {
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ret = 0;
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goto out;
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}
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path->slots[0]--;
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}
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keep = 0;
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bookend = 0;
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found_extent = 0;
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found_inline = 0;
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extent = NULL;
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leaf = btrfs_buffer_leaf(path->nodes[0]);
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slot = path->slots[0];
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btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
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if (key.offset >= end || key.objectid != inode->i_ino) {
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ret = 0;
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goto out;
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}
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if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) {
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ret = 0;
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goto out;
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}
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extent = btrfs_item_ptr(leaf, slot,
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struct btrfs_file_extent_item);
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found_type = btrfs_file_extent_type(extent);
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if (found_type == BTRFS_FILE_EXTENT_REG) {
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extent_end = key.offset +
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(btrfs_file_extent_num_blocks(extent) <<
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inode->i_blkbits);
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found_extent = 1;
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} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
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found_inline = 1;
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extent_end = key.offset +
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btrfs_file_extent_inline_len(leaf->items + slot);
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}
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/* we found nothing we can drop */
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if (!found_extent && !found_inline) {
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ret = 0;
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goto out;
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}
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/* we found nothing inside the range */
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if (search_start >= extent_end) {
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ret = 0;
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goto out;
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}
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/* FIXME, there's only one inline extent allowed right now */
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if (found_inline) {
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u64 mask = root->blocksize - 1;
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search_start = (extent_end + mask) & ~mask;
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} else
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search_start = extent_end;
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if (end < extent_end && end >= key.offset) {
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if (found_extent) {
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u64 disk_blocknr =
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btrfs_file_extent_disk_blocknr(extent);
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u64 disk_num_blocks =
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btrfs_file_extent_disk_num_blocks(extent);
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memcpy(&old, extent, sizeof(old));
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if (disk_blocknr != 0) {
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ret = btrfs_inc_extent_ref(trans, root,
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disk_blocknr, disk_num_blocks);
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BUG_ON(ret);
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}
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}
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WARN_ON(found_inline);
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bookend = 1;
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}
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/* truncate existing extent */
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if (start > key.offset) {
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u64 new_num;
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u64 old_num;
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keep = 1;
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WARN_ON(start & (root->blocksize - 1));
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if (found_extent) {
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new_num = (start - key.offset) >>
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inode->i_blkbits;
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old_num = btrfs_file_extent_num_blocks(extent);
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*hint_block =
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btrfs_file_extent_disk_blocknr(extent);
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if (btrfs_file_extent_disk_blocknr(extent)) {
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inode->i_blocks -=
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(old_num - new_num) << 3;
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}
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btrfs_set_file_extent_num_blocks(extent,
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new_num);
|
||||
mark_buffer_dirty(path->nodes[0]);
|
||||
} else {
|
||||
WARN_ON(1);
|
||||
}
|
||||
}
|
||||
/* delete the entire extent */
|
||||
if (!keep) {
|
||||
u64 disk_blocknr = 0;
|
||||
u64 disk_num_blocks = 0;
|
||||
u64 extent_num_blocks = 0;
|
||||
if (found_extent) {
|
||||
disk_blocknr =
|
||||
btrfs_file_extent_disk_blocknr(extent);
|
||||
disk_num_blocks =
|
||||
btrfs_file_extent_disk_num_blocks(extent);
|
||||
extent_num_blocks =
|
||||
btrfs_file_extent_num_blocks(extent);
|
||||
*hint_block =
|
||||
btrfs_file_extent_disk_blocknr(extent);
|
||||
}
|
||||
ret = btrfs_del_item(trans, root, path);
|
||||
BUG_ON(ret);
|
||||
btrfs_release_path(root, path);
|
||||
extent = NULL;
|
||||
if (found_extent && disk_blocknr != 0) {
|
||||
inode->i_blocks -= extent_num_blocks << 3;
|
||||
ret = btrfs_free_extent(trans, root,
|
||||
disk_blocknr,
|
||||
disk_num_blocks, 0);
|
||||
}
|
||||
|
||||
BUG_ON(ret);
|
||||
if (!bookend && search_start >= end) {
|
||||
ret = 0;
|
||||
goto out;
|
||||
}
|
||||
if (!bookend)
|
||||
continue;
|
||||
}
|
||||
/* create bookend, splitting the extent in two */
|
||||
if (bookend && found_extent) {
|
||||
struct btrfs_key ins;
|
||||
ins.objectid = inode->i_ino;
|
||||
ins.offset = end;
|
||||
ins.flags = 0;
|
||||
btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
|
||||
|
||||
btrfs_release_path(root, path);
|
||||
ret = btrfs_insert_empty_item(trans, root, path, &ins,
|
||||
sizeof(*extent));
|
||||
BUG_ON(ret);
|
||||
extent = btrfs_item_ptr(
|
||||
btrfs_buffer_leaf(path->nodes[0]),
|
||||
path->slots[0],
|
||||
struct btrfs_file_extent_item);
|
||||
btrfs_set_file_extent_disk_blocknr(extent,
|
||||
btrfs_file_extent_disk_blocknr(&old));
|
||||
btrfs_set_file_extent_disk_num_blocks(extent,
|
||||
btrfs_file_extent_disk_num_blocks(&old));
|
||||
|
||||
btrfs_set_file_extent_offset(extent,
|
||||
btrfs_file_extent_offset(&old) +
|
||||
((end - key.offset) >> inode->i_blkbits));
|
||||
WARN_ON(btrfs_file_extent_num_blocks(&old) <
|
||||
(extent_end - end) >> inode->i_blkbits);
|
||||
btrfs_set_file_extent_num_blocks(extent,
|
||||
(extent_end - end) >> inode->i_blkbits);
|
||||
|
||||
btrfs_set_file_extent_type(extent,
|
||||
BTRFS_FILE_EXTENT_REG);
|
||||
btrfs_set_file_extent_generation(extent,
|
||||
btrfs_file_extent_generation(&old));
|
||||
btrfs_mark_buffer_dirty(path->nodes[0]);
|
||||
if (btrfs_file_extent_disk_blocknr(&old) != 0) {
|
||||
inode->i_blocks +=
|
||||
btrfs_file_extent_num_blocks(extent) << 3;
|
||||
}
|
||||
ret = 0;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
out:
|
||||
btrfs_free_path(path);
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* this gets pages into the page cache and locks them down
|
||||
*/
|
||||
static int prepare_pages(struct btrfs_root *root,
|
||||
struct file *file,
|
||||
struct page **pages,
|
||||
size_t num_pages,
|
||||
loff_t pos,
|
||||
unsigned long first_index,
|
||||
unsigned long last_index,
|
||||
size_t write_bytes,
|
||||
u64 alloc_extent_start)
|
||||
{
|
||||
int i;
|
||||
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
||||
struct inode *inode = file->f_path.dentry->d_inode;
|
||||
int offset;
|
||||
int err = 0;
|
||||
int this_write;
|
||||
struct buffer_head *bh;
|
||||
struct buffer_head *head;
|
||||
loff_t isize = i_size_read(inode);
|
||||
|
||||
memset(pages, 0, num_pages * sizeof(struct page *));
|
||||
|
||||
for (i = 0; i < num_pages; i++) {
|
||||
pages[i] = grab_cache_page(inode->i_mapping, index + i);
|
||||
if (!pages[i]) {
|
||||
err = -ENOMEM;
|
||||
goto failed_release;
|
||||
}
|
||||
cancel_dirty_page(pages[i], PAGE_CACHE_SIZE);
|
||||
wait_on_page_writeback(pages[i]);
|
||||
offset = pos & (PAGE_CACHE_SIZE -1);
|
||||
this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
|
||||
if (!page_has_buffers(pages[i])) {
|
||||
create_empty_buffers(pages[i],
|
||||
root->fs_info->sb->s_blocksize,
|
||||
(1 << BH_Uptodate));
|
||||
}
|
||||
head = page_buffers(pages[i]);
|
||||
bh = head;
|
||||
do {
|
||||
err = btrfs_map_bh_to_logical(root, bh,
|
||||
alloc_extent_start);
|
||||
BUG_ON(err);
|
||||
if (err)
|
||||
goto failed_truncate;
|
||||
bh = bh->b_this_page;
|
||||
if (alloc_extent_start)
|
||||
alloc_extent_start++;
|
||||
} while (bh != head);
|
||||
pos += this_write;
|
||||
WARN_ON(this_write > write_bytes);
|
||||
write_bytes -= this_write;
|
||||
}
|
||||
return 0;
|
||||
|
||||
failed_release:
|
||||
btrfs_drop_pages(pages, num_pages);
|
||||
return err;
|
||||
|
||||
failed_truncate:
|
||||
btrfs_drop_pages(pages, num_pages);
|
||||
if (pos > isize)
|
||||
vmtruncate(inode, isize);
|
||||
return err;
|
||||
}
|
||||
|
||||
static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
|
||||
size_t count, loff_t *ppos)
|
||||
{
|
||||
loff_t pos;
|
||||
size_t num_written = 0;
|
||||
int err = 0;
|
||||
int ret = 0;
|
||||
struct inode *inode = file->f_path.dentry->d_inode;
|
||||
struct btrfs_root *root = BTRFS_I(inode)->root;
|
||||
struct page *pages[8];
|
||||
struct page *pinned[2];
|
||||
unsigned long first_index;
|
||||
unsigned long last_index;
|
||||
u64 start_pos;
|
||||
u64 num_blocks;
|
||||
u64 alloc_extent_start;
|
||||
u64 hint_block;
|
||||
struct btrfs_trans_handle *trans;
|
||||
struct btrfs_key ins;
|
||||
pinned[0] = NULL;
|
||||
pinned[1] = NULL;
|
||||
if (file->f_flags & O_DIRECT)
|
||||
return -EINVAL;
|
||||
pos = *ppos;
|
||||
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
|
||||
current->backing_dev_info = inode->i_mapping->backing_dev_info;
|
||||
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
|
||||
if (err)
|
||||
goto out;
|
||||
if (count == 0)
|
||||
goto out;
|
||||
err = remove_suid(file->f_path.dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
file_update_time(file);
|
||||
|
||||
start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
|
||||
num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
|
||||
inode->i_blkbits;
|
||||
|
||||
mutex_lock(&inode->i_mutex);
|
||||
first_index = pos >> PAGE_CACHE_SHIFT;
|
||||
last_index = (pos + count) >> PAGE_CACHE_SHIFT;
|
||||
|
||||
/*
|
||||
* there are lots of better ways to do this, but this code
|
||||
* makes sure the first and last page in the file range are
|
||||
* up to date and ready for cow
|
||||
*/
|
||||
if ((pos & (PAGE_CACHE_SIZE - 1))) {
|
||||
pinned[0] = grab_cache_page(inode->i_mapping, first_index);
|
||||
if (!PageUptodate(pinned[0])) {
|
||||
ret = mpage_readpage(pinned[0], btrfs_get_block);
|
||||
BUG_ON(ret);
|
||||
wait_on_page_locked(pinned[0]);
|
||||
} else {
|
||||
unlock_page(pinned[0]);
|
||||
}
|
||||
}
|
||||
if ((pos + count) & (PAGE_CACHE_SIZE - 1)) {
|
||||
pinned[1] = grab_cache_page(inode->i_mapping, last_index);
|
||||
if (!PageUptodate(pinned[1])) {
|
||||
ret = mpage_readpage(pinned[1], btrfs_get_block);
|
||||
BUG_ON(ret);
|
||||
wait_on_page_locked(pinned[1]);
|
||||
} else {
|
||||
unlock_page(pinned[1]);
|
||||
}
|
||||
}
|
||||
|
||||
mutex_lock(&root->fs_info->fs_mutex);
|
||||
trans = btrfs_start_transaction(root, 1);
|
||||
if (!trans) {
|
||||
err = -ENOMEM;
|
||||
mutex_unlock(&root->fs_info->fs_mutex);
|
||||
goto out_unlock;
|
||||
}
|
||||
btrfs_set_trans_block_group(trans, inode);
|
||||
/* FIXME blocksize != 4096 */
|
||||
inode->i_blocks += num_blocks << 3;
|
||||
hint_block = 0;
|
||||
|
||||
/* FIXME...EIEIO, ENOSPC and more */
|
||||
|
||||
/* step one, delete the existing extents in this range */
|
||||
if (start_pos < inode->i_size) {
|
||||
/* FIXME blocksize != pagesize */
|
||||
ret = btrfs_drop_extents(trans, root, inode,
|
||||
start_pos,
|
||||
(pos + count + root->blocksize -1) &
|
||||
~((u64)root->blocksize - 1),
|
||||
&hint_block);
|
||||
BUG_ON(ret);
|
||||
}
|
||||
|
||||
/* insert any holes we need to create */
|
||||
if (inode->i_size < start_pos) {
|
||||
u64 last_pos_in_file;
|
||||
u64 hole_size;
|
||||
u64 mask = root->blocksize - 1;
|
||||
last_pos_in_file = (inode->i_size + mask) & ~mask;
|
||||
hole_size = (start_pos - last_pos_in_file + mask) & ~mask;
|
||||
hole_size >>= inode->i_blkbits;
|
||||
if (last_pos_in_file < start_pos) {
|
||||
ret = btrfs_insert_file_extent(trans, root,
|
||||
inode->i_ino,
|
||||
last_pos_in_file,
|
||||
0, 0, hole_size);
|
||||
}
|
||||
BUG_ON(ret);
|
||||
}
|
||||
|
||||
/*
|
||||
* either allocate an extent for the new bytes or setup the key
|
||||
* to show we are doing inline data in the extent
|
||||
*/
|
||||
if (inode->i_size >= PAGE_CACHE_SIZE || pos + count < inode->i_size ||
|
||||
pos + count - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
|
||||
ret = btrfs_alloc_extent(trans, root, inode->i_ino,
|
||||
num_blocks, hint_block, (u64)-1,
|
||||
&ins, 1);
|
||||
BUG_ON(ret);
|
||||
ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
|
||||
start_pos, ins.objectid, ins.offset,
|
||||
ins.offset);
|
||||
BUG_ON(ret);
|
||||
} else {
|
||||
ins.offset = 0;
|
||||
ins.objectid = 0;
|
||||
}
|
||||
BUG_ON(ret);
|
||||
alloc_extent_start = ins.objectid;
|
||||
ret = btrfs_end_transaction(trans, root);
|
||||
mutex_unlock(&root->fs_info->fs_mutex);
|
||||
|
||||
while(count > 0) {
|
||||
size_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
||||
size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
|
||||
size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
|
||||
PAGE_CACHE_SHIFT;
|
||||
|
||||
memset(pages, 0, sizeof(pages));
|
||||
ret = prepare_pages(root, file, pages, num_pages,
|
||||
pos, first_index, last_index,
|
||||
write_bytes, alloc_extent_start);
|
||||
BUG_ON(ret);
|
||||
|
||||
/* FIXME blocks != pagesize */
|
||||
if (alloc_extent_start)
|
||||
alloc_extent_start += num_pages;
|
||||
ret = btrfs_copy_from_user(pos, num_pages,
|
||||
write_bytes, pages, buf);
|
||||
BUG_ON(ret);
|
||||
|
||||
ret = dirty_and_release_pages(NULL, root, file, pages,
|
||||
num_pages, pos, write_bytes);
|
||||
BUG_ON(ret);
|
||||
btrfs_drop_pages(pages, num_pages);
|
||||
|
||||
buf += write_bytes;
|
||||
count -= write_bytes;
|
||||
pos += write_bytes;
|
||||
num_written += write_bytes;
|
||||
|
||||
balance_dirty_pages_ratelimited(inode->i_mapping);
|
||||
btrfs_btree_balance_dirty(root);
|
||||
cond_resched();
|
||||
}
|
||||
out_unlock:
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
out:
|
||||
if (pinned[0])
|
||||
page_cache_release(pinned[0]);
|
||||
if (pinned[1])
|
||||
page_cache_release(pinned[1]);
|
||||
*ppos = pos;
|
||||
current->backing_dev_info = NULL;
|
||||
mark_inode_dirty(inode);
|
||||
return num_written ? num_written : err;
|
||||
}
|
||||
|
||||
/*
|
||||
* FIXME, do this by stuffing the csum we want in the info hanging off
|
||||
* page->private. For now, verify file csums on read
|
||||
*/
|
||||
static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
|
||||
unsigned long offset, unsigned long size)
|
||||
{
|
||||
char *kaddr;
|
||||
unsigned long left, count = desc->count;
|
||||
struct inode *inode = page->mapping->host;
|
||||
|
||||
if (size > count)
|
||||
size = count;
|
||||
|
||||
if (!PageChecked(page)) {
|
||||
/* FIXME, do it per block */
|
||||
struct btrfs_root *root = BTRFS_I(inode)->root;
|
||||
int ret;
|
||||
struct buffer_head *bh;
|
||||
|
||||
if (page_has_buffers(page)) {
|
||||
bh = page_buffers(page);
|
||||
if (!buffer_mapped(bh)) {
|
||||
SetPageChecked(page);
|
||||
goto checked;
|
||||
}
|
||||
}
|
||||
|
||||
ret = btrfs_csum_verify_file_block(root,
|
||||
page->mapping->host->i_ino,
|
||||
page->index << PAGE_CACHE_SHIFT,
|
||||
kmap(page), PAGE_CACHE_SIZE);
|
||||
if (ret) {
|
||||
if (ret != -ENOENT) {
|
||||
printk("failed to verify ino %lu page %lu ret %d\n",
|
||||
page->mapping->host->i_ino,
|
||||
page->index, ret);
|
||||
memset(page_address(page), 1, PAGE_CACHE_SIZE);
|
||||
flush_dcache_page(page);
|
||||
}
|
||||
}
|
||||
SetPageChecked(page);
|
||||
kunmap(page);
|
||||
}
|
||||
checked:
|
||||
/*
|
||||
* Faults on the destination of a read are common, so do it before
|
||||
* taking the kmap.
|
||||
*/
|
||||
if (!fault_in_pages_writeable(desc->arg.buf, size)) {
|
||||
kaddr = kmap_atomic(page, KM_USER0);
|
||||
left = __copy_to_user_inatomic(desc->arg.buf,
|
||||
kaddr + offset, size);
|
||||
kunmap_atomic(kaddr, KM_USER0);
|
||||
if (left == 0)
|
||||
goto success;
|
||||
}
|
||||
|
||||
/* Do it the slow way */
|
||||
kaddr = kmap(page);
|
||||
left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
|
||||
kunmap(page);
|
||||
|
||||
if (left) {
|
||||
size -= left;
|
||||
desc->error = -EFAULT;
|
||||
}
|
||||
success:
|
||||
desc->count = count - size;
|
||||
desc->written += size;
|
||||
desc->arg.buf += size;
|
||||
return size;
|
||||
}
|
||||
|
||||
/**
|
||||
* btrfs_file_aio_read - filesystem read routine, with a mod to csum verify
|
||||
* @iocb: kernel I/O control block
|
||||
* @iov: io vector request
|
||||
* @nr_segs: number of segments in the iovec
|
||||
* @pos: current file position
|
||||
*/
|
||||
static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
|
||||
unsigned long nr_segs, loff_t pos)
|
||||
{
|
||||
struct file *filp = iocb->ki_filp;
|
||||
ssize_t retval;
|
||||
unsigned long seg;
|
||||
size_t count;
|
||||
loff_t *ppos = &iocb->ki_pos;
|
||||
|
||||
count = 0;
|
||||
for (seg = 0; seg < nr_segs; seg++) {
|
||||
const struct iovec *iv = &iov[seg];
|
||||
|
||||
/*
|
||||
* If any segment has a negative length, or the cumulative
|
||||
* length ever wraps negative then return -EINVAL.
|
||||
*/
|
||||
count += iv->iov_len;
|
||||
if (unlikely((ssize_t)(count|iv->iov_len) < 0))
|
||||
return -EINVAL;
|
||||
if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
|
||||
continue;
|
||||
if (seg == 0)
|
||||
return -EFAULT;
|
||||
nr_segs = seg;
|
||||
count -= iv->iov_len; /* This segment is no good */
|
||||
break;
|
||||
}
|
||||
retval = 0;
|
||||
if (count) {
|
||||
for (seg = 0; seg < nr_segs; seg++) {
|
||||
read_descriptor_t desc;
|
||||
|
||||
desc.written = 0;
|
||||
desc.arg.buf = iov[seg].iov_base;
|
||||
desc.count = iov[seg].iov_len;
|
||||
if (desc.count == 0)
|
||||
continue;
|
||||
desc.error = 0;
|
||||
do_generic_file_read(filp, ppos, &desc,
|
||||
btrfs_read_actor);
|
||||
retval += desc.written;
|
||||
if (desc.error) {
|
||||
retval = retval ?: desc.error;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
return retval;
|
||||
}
|
||||
|
||||
static int btrfs_sync_file(struct file *file,
|
||||
struct dentry *dentry, int datasync)
|
||||
{
|
||||
struct inode *inode = dentry->d_inode;
|
||||
struct btrfs_root *root = BTRFS_I(inode)->root;
|
||||
int ret;
|
||||
struct btrfs_trans_handle *trans;
|
||||
|
||||
/*
|
||||
* FIXME, use inode generation number to check if we can skip the
|
||||
* commit
|
||||
*/
|
||||
mutex_lock(&root->fs_info->fs_mutex);
|
||||
trans = btrfs_start_transaction(root, 1);
|
||||
if (!trans) {
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
ret = btrfs_commit_transaction(trans, root);
|
||||
mutex_unlock(&root->fs_info->fs_mutex);
|
||||
out:
|
||||
return ret > 0 ? EIO : ret;
|
||||
}
|
||||
|
||||
struct file_operations btrfs_file_operations = {
|
||||
.llseek = generic_file_llseek,
|
||||
.read = do_sync_read,
|
||||
.aio_read = btrfs_file_aio_read,
|
||||
.write = btrfs_file_write,
|
||||
.mmap = generic_file_mmap,
|
||||
.open = generic_file_open,
|
||||
.ioctl = btrfs_ioctl,
|
||||
.fsync = btrfs_sync_file,
|
||||
#ifdef CONFIG_COMPAT
|
||||
.compat_ioctl = btrfs_compat_ioctl,
|
||||
#endif
|
||||
};
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
2879
fs/btrfs/super.c
2879
fs/btrfs/super.c
File diff suppressed because it is too large
Load Diff
Loading…
Reference in New Issue