set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
&BTRFS_I(inode)->runtime_flags);
+ /*
+ * We don't persist the id of the transaction where an unlink operation
+ * against the inode was last made. So here we assume the inode might
+ * have been evicted, and therefore the exact value of last_unlink_trans
+ * lost, and set it to last_trans to avoid metadata inconsistencies
+ * between the inode and its parent if the inode is fsync'ed and the log
+ * replayed. For example, in the scenario:
+ *
+ * touch mydir/foo
+ * ln mydir/foo mydir/bar
+ * sync
+ * unlink mydir/bar
+ * echo 2 > /proc/sys/vm/drop_caches # evicts inode
+ * xfs_io -c fsync mydir/foo
+ * <power failure>
+ * mount fs, triggers fsync log replay
+ *
+ * We must make sure that when we fsync our inode foo we also log its
+ * parent inode, otherwise after log replay the parent still has the
+ * dentry with the "bar" name but our inode foo has a link count of 1
+ * and doesn't have an inode ref with the name "bar" anymore.
+ *
+ * Setting last_unlink_trans to last_trans is a pessimistic approach,
+ * but it guarantees correctness at the expense of ocassional full
+ * transaction commits on fsync if our inode is a directory, or if our
+ * inode is not a directory, logging its parent unnecessarily.
+ */
+ BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans;
+
path->slots[0]++;
if (inode->i_nlink != 1 ||
path->slots[0] >= btrfs_header_nritems(leaf))
goto no_delete;
}
/* do we really want it for ->i_nlink > 0 and zero btrfs_root_refs? */
- btrfs_wait_ordered_range(inode, 0, (u64)-1);
+ if (!special_file(inode->i_mode))
+ btrfs_wait_ordered_range(inode, 0, (u64)-1);
btrfs_free_io_failure_record(inode, 0, (u64)-1);
trace_btrfs_get_extent(root, em);
- if (path)
- btrfs_free_path(path);
+ btrfs_free_path(path);
if (trans) {
ret = btrfs_end_transaction(trans, root);
if (!err)
return em;
}
+struct btrfs_dio_data {
+ u64 outstanding_extents;
+ u64 reserve;
+};
static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create)
struct extent_map *em;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct extent_state *cached_state = NULL;
+ struct btrfs_dio_data *dio_data = NULL;
u64 start = iblock << inode->i_blkbits;
u64 lockstart, lockend;
u64 len = bh_result->b_size;
- u64 *outstanding_extents = NULL;
int unlock_bits = EXTENT_LOCKED;
int ret = 0;
* that anything that needs to check if there's a transction doesn't get
* confused.
*/
- outstanding_extents = current->journal_info;
+ dio_data = current->journal_info;
current->journal_info = NULL;
}
* within our reservation, otherwise we need to adjust our inode
* counter appropriately.
*/
- if (*outstanding_extents) {
- (*outstanding_extents)--;
+ if (dio_data->outstanding_extents) {
+ (dio_data->outstanding_extents)--;
} else {
spin_lock(&BTRFS_I(inode)->lock);
BTRFS_I(inode)->outstanding_extents++;
spin_unlock(&BTRFS_I(inode)->lock);
}
- current->journal_info = outstanding_extents;
btrfs_free_reserved_data_space(inode, len);
- set_bit(BTRFS_INODE_DIO_READY, &BTRFS_I(inode)->runtime_flags);
+ WARN_ON(dio_data->reserve < len);
+ dio_data->reserve -= len;
+ current->journal_info = dio_data;
}
/*
unlock_err:
clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
unlock_bits, 1, 0, &cached_state, GFP_NOFS);
- if (outstanding_extents)
- current->journal_info = outstanding_extents;
+ if (dio_data)
+ current->journal_info = dio_data;
return ret;
}
static struct bio *btrfs_dio_bio_alloc(struct block_device *bdev,
u64 first_sector, gfp_t gfp_flags)
{
- return btrfs_bio_alloc(bdev, first_sector, BIO_MAX_PAGES, gfp_flags);
+ struct bio *bio;
+ bio = btrfs_bio_alloc(bdev, first_sector, BIO_MAX_PAGES, gfp_flags);
+ if (bio)
+ bio_associate_current(bio);
+ return bio;
}
static inline int btrfs_lookup_and_bind_dio_csum(struct btrfs_root *root,
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
- u64 outstanding_extents = 0;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_dio_data dio_data = { 0 };
size_t count = 0;
int flags = 0;
bool wakeup = true;
ret = btrfs_delalloc_reserve_space(inode, count);
if (ret)
goto out;
- outstanding_extents = div64_u64(count +
+ dio_data.outstanding_extents = div64_u64(count +
BTRFS_MAX_EXTENT_SIZE - 1,
BTRFS_MAX_EXTENT_SIZE);
* do the accounting properly if we go over the number we
* originally calculated. Abuse current->journal_info for this.
*/
- current->journal_info = &outstanding_extents;
+ dio_data.reserve = round_up(count, root->sectorsize);
+ current->journal_info = &dio_data;
} else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
&BTRFS_I(inode)->runtime_flags)) {
inode_dio_end(inode);
if (iov_iter_rw(iter) == WRITE) {
current->journal_info = NULL;
if (ret < 0 && ret != -EIOCBQUEUED) {
- /*
- * If the error comes from submitting stage,
- * btrfs_get_blocsk_direct() has free'd data space,
- * and metadata space will be handled by
- * finish_ordered_fn, don't do that again to make
- * sure bytes_may_use is correct.
- */
- if (!test_and_clear_bit(BTRFS_INODE_DIO_READY,
- &BTRFS_I(inode)->runtime_flags))
- btrfs_delalloc_release_space(inode, count);
+ if (dio_data.reserve)
+ btrfs_delalloc_release_space(inode,
+ dio_data.reserve);
} else if (ret >= 0 && (size_t)ret < count)
btrfs_delalloc_release_space(inode,
count - (size_t)ret);
projects / firefly-linux-kernel-4.4.55.git / blobdiff