[PATCH] f2fs: fix to release compress file for F2FS_IOC_RESERVE_COMPRESS_BLOCKS when has no space

From: Yangtao Li
Date: Fri Feb 10 2023 - 05:20:52 EST


When the released file is reserving and the space is insufficient,
the fsck flag is set incorrectly, and lead to the file cannot be
reserved and released normally.

$ mount -t f2fs -o compress_extension=*,compress_mode=user /mnt/9p/f2fs.img
/mnt/f2fs/
$ dd if=/dev/zero of=/mnt/f2fs/800M bs=1M count=800
$ dd if=/dev/zero of=/mnt/f2fs/60M bs=1M count=60
$ f2fs_io compress /mnt/f2fs/60M
$ ./mnt/9p/my_f2fs_io release_cblocks /mnt/f2fs/60M
11520
$ dd if=/dev/zero of=/mnt/f2fs/30M bs=1M count=30
$ f2fs_io reserve_cblocks /mnt/f2fs/60M
[ 56.399712] F2FS-fs (loop0): f2fs_reserve_compress_blocks: partial blocks
were released i_ino=cf iblocks=76104, reserved=5220, compr_blocks=5655,
run fsck to fix.
F2FS_IOC_RESERVE_COMPRESS_BLOCKS failed: No space left on device

$ ./mnt/9p/my_f2fs_io reserve_cblocks /mnt/f2fs/60M
0
$ ./mnt/9p/my_f2fs_io release_cblocks /mnt/f2fs/60M
F2FS_IOC_RELEASE_COMPRESS_BLOCKS failed: Invalid argument

$ rm /mnt/f2fs/30M
$ ./mnt/9p/my_f2fs_io reserve_cblocks /mnt/f2fs/60M
0
$ ./mnt/9p/my_f2fs_io release_cblocks /mnt/f2fs/60M
F2FS_IOC_RELEASE_COMPRESS_BLOCKS failed: Invalid argument

In this case, let's release back the reserved part of the compressed file.

Fixes: c75488fb4d82 ("f2fs: introduce F2FS_IOC_RESERVE_COMPRESS_BLOCKS")
Signed-off-by: Qi Han <hanqi@xxxxxxxx>
Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
fs/f2fs/file.c | 97 ++++++++++++++++++++++++++++++++------------------
1 file changed, 63 insertions(+), 34 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 300eae8b5415..8f3f55ac153a 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3427,11 +3427,52 @@ static int release_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
return released_blocks;
}

+static int f2fs_do_release_compress_blocks(struct inode *inode,
+ pgoff_t page_count, unsigned int *released_blocks)
+{
+ pgoff_t page_idx = 0;
+ int ret;
+
+ while (page_idx < page_count) {
+ struct dnode_of_data dn;
+ pgoff_t end_offset, count;
+
+ set_new_dnode(&dn, inode, NULL, NULL, 0);
+ ret = f2fs_get_dnode_of_data(&dn, page_idx, LOOKUP_NODE);
+ if (ret) {
+ if (ret == -ENOENT) {
+ page_idx = f2fs_get_next_page_offset(&dn,
+ page_idx);
+ ret = 0;
+ continue;
+ }
+ break;
+ }
+
+ end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
+ count = min(end_offset - dn.ofs_in_node, page_count - page_idx);
+ count = round_up(count, F2FS_I(inode)->i_cluster_size);
+
+ ret = release_compress_blocks(&dn, count);
+
+ f2fs_put_dnode(&dn);
+
+ if (ret < 0)
+ break;
+
+ page_idx += count;
+ if (released_blocks)
+ *released_blocks += ret;
+ }
+
+ return ret;
+}
+
static int f2fs_release_compress_blocks(struct file *filp, unsigned long arg)
{
struct inode *inode = file_inode(filp);
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
- pgoff_t page_idx = 0, last_idx;
+ pgoff_t last_idx;
unsigned int released_blocks = 0;
int ret;
int writecount;
@@ -3481,36 +3522,7 @@ static int f2fs_release_compress_blocks(struct file *filp, unsigned long arg)

last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);

- while (page_idx < last_idx) {
- struct dnode_of_data dn;
- pgoff_t end_offset, count;
-
- set_new_dnode(&dn, inode, NULL, NULL, 0);
- ret = f2fs_get_dnode_of_data(&dn, page_idx, LOOKUP_NODE);
- if (ret) {
- if (ret == -ENOENT) {
- page_idx = f2fs_get_next_page_offset(&dn,
- page_idx);
- ret = 0;
- continue;
- }
- break;
- }
-
- end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
- count = min(end_offset - dn.ofs_in_node, last_idx - page_idx);
- count = round_up(count, F2FS_I(inode)->i_cluster_size);
-
- ret = release_compress_blocks(&dn, count);
-
- f2fs_put_dnode(&dn);
-
- if (ret < 0)
- break;
-
- page_idx += count;
- released_blocks += ret;
- }
+ ret = f2fs_do_release_compress_blocks(inode, last_idx, &released_blocks);

filemap_invalidate_unlock(inode->i_mapping);
f2fs_up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
@@ -3585,8 +3597,22 @@ static int reserve_compress_blocks(struct dnode_of_data *dn, pgoff_t count)
if (ret)
return ret;

- if (reserved != cluster_size - compr_blocks)
- return -ENOSPC;
+ if (reserved != cluster_size - compr_blocks) {
+ dec_valid_block_count(sbi, dn->inode, reserved);
+
+ for (i = cluster_size - 1; i > 0; i--) {
+ dn->ofs_in_node--;
+ blkaddr = f2fs_data_blkaddr(dn);
+
+ if (__is_valid_data_blkaddr(blkaddr)) {
+ dn->ofs_in_node -= i;
+ return -ENOSPC;
+ }
+
+ dn->data_blkaddr = NULL_ADDR;
+ f2fs_set_data_blkaddr(dn);
+ }
+ }

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

@@ -3604,6 +3630,7 @@ static int f2fs_reserve_compress_blocks(struct file *filp, unsigned long arg)
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
pgoff_t page_idx = 0, last_idx;
unsigned int reserved_blocks = 0;
+ struct dnode_of_data dn;
int ret;

if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))
@@ -3637,7 +3664,6 @@ static int f2fs_reserve_compress_blocks(struct file *filp, unsigned long arg)
last_idx = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);

while (page_idx < last_idx) {
- struct dnode_of_data dn;
pgoff_t end_offset, count;

set_new_dnode(&dn, inode, NULL, NULL, 0);
@@ -3667,6 +3693,9 @@ static int f2fs_reserve_compress_blocks(struct file *filp, unsigned long arg)
reserved_blocks += ret;
}

+ if (ret == -ENOSPC)
+ f2fs_do_release_compress_blocks(inode, page_idx + dn.ofs_in_node, NULL);
+
filemap_invalidate_unlock(inode->i_mapping);
f2fs_up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);

--
2.25.1