[PATCH v4 4/6] f2fs: compress: fix to avoid inconsistence bewteen i_blocks and dnode

From: Chao Yu
Date: Thu Jan 11 2024 - 01:43:08 EST


In reserve_compress_blocks(), we update blkaddrs of dnode in prior to
inc_valid_block_count(), it may cause inconsistent status bewteen
i_blocks and blkaddrs once inc_valid_block_count() fails.

To fix this issue, it needs to reverse their invoking order.

Fixes: c75488fb4d82 ("f2fs: introduce F2FS_IOC_RESERVE_COMPRESS_BLOCKS")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
fs/f2fs/data.c | 5 +++--
fs/f2fs/f2fs.h | 7 ++++++-
fs/f2fs/file.c | 26 ++++++++++++++------------
fs/f2fs/segment.c | 2 +-
4 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b171a9980f6a..8d2ace723310 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1219,7 +1219,8 @@ int f2fs_reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)

if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
return -EPERM;
- if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
+ err = inc_valid_block_count(sbi, dn->inode, &count, true);
+ if (unlikely(err))
return err;

trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
@@ -1476,7 +1477,7 @@ static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)

dn->data_blkaddr = f2fs_data_blkaddr(dn);
if (dn->data_blkaddr == NULL_ADDR) {
- err = inc_valid_block_count(sbi, dn->inode, &count);
+ err = inc_valid_block_count(sbi, dn->inode, &count, true);
if (unlikely(err))
return err;
}
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 50f3d546ded8..69e71460a950 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2252,7 +2252,7 @@ static inline bool __allow_reserved_blocks(struct f2fs_sb_info *sbi,

static inline void f2fs_i_blocks_write(struct inode *, block_t, bool, bool);
static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
- struct inode *inode, blkcnt_t *count)
+ struct inode *inode, blkcnt_t *count, bool partial)
{
blkcnt_t diff = 0, release = 0;
block_t avail_user_block_count;
@@ -2292,6 +2292,11 @@ static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
avail_user_block_count = 0;
}
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
+ if (!partial) {
+ spin_unlock(&sbi->stat_lock);
+ goto enospc;
+ }
+
diff = sbi->total_valid_block_count - avail_user_block_count;
if (diff > *count)
diff = *count;
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 80d9c4c096f0..53c495651789 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3614,14 +3614,16 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
blkcnt_t reserved;
int ret;

- for (i = 0; i < cluster_size; i++, dn->ofs_in_node++) {
- blkaddr = f2fs_data_blkaddr(dn);
+ for (i = 0; i < cluster_size; i++) {
+ blkaddr = data_blkaddr(dn->inode, dn->node_page,
+ dn->ofs_in_node + i);

if (i == 0) {
- if (blkaddr == COMPRESS_ADDR)
- continue;
- dn->ofs_in_node += cluster_size;
- goto next;
+ if (blkaddr != COMPRESS_ADDR) {
+ dn->ofs_in_node += cluster_size;
+ goto next;
+ }
+ continue;
}

/*
@@ -3634,20 +3636,20 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
compr_blocks++;
continue;
}
-
- f2fs_set_data_blkaddr(dn, NEW_ADDR);
}

reserved = cluster_size - compr_blocks;
if (!reserved)
goto next;

- ret = inc_valid_block_count(sbi, dn->inode, &reserved);
- if (ret)
+ ret = inc_valid_block_count(sbi, dn->inode, &reserved, false);
+ if (unlikely(ret))
return ret;

- if (reserved != cluster_size - compr_blocks)
- return -ENOSPC;
+ for (i = 0; i < cluster_size; i++, dn->ofs_in_node++) {
+ if (f2fs_data_blkaddr(dn) == NULL_ADDR)
+ f2fs_set_data_blkaddr(dn, NEW_ADDR);
+ }

f2fs_i_compr_blocks_update(dn->inode, compr_blocks, true);

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 4c8836ded90f..ef5b3848426b 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -248,7 +248,7 @@ static int __replace_atomic_write_block(struct inode *inode, pgoff_t index,
} else {
blkcnt_t count = 1;

- err = inc_valid_block_count(sbi, inode, &count);
+ err = inc_valid_block_count(sbi, inode, &count, true);
if (err) {
f2fs_put_dnode(&dn);
return err;
--
2.40.1