2024-03-22 17:50:01

by Daeho Jeong

[permalink] [raw]
Subject: [PATCH v4] f2fs: prevent writing without fallocate() for pinned files

From: Daeho Jeong <[email protected]>

In a case writing without fallocate(), we can't guarantee it's allocated
in the conventional area for zoned stroage.

Signed-off-by: Daeho Jeong <[email protected]>
---
v2: covered the direct io case
v3: covered the mkwrite case
v4: moved pin file check position in prepare_write_begin()
---
fs/f2fs/data.c | 20 ++++++++++++++++----
fs/f2fs/file.c | 16 ++++++++--------
2 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index c21b92f18463..88896989bb28 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1584,8 +1584,11 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag)

/* use out-place-update for direct IO under LFS mode */
if (map->m_may_create &&
- (is_hole || (f2fs_lfs_mode(sbi) && flag == F2FS_GET_BLOCK_DIO))) {
- if (unlikely(f2fs_cp_error(sbi))) {
+ (is_hole || (f2fs_lfs_mode(sbi) && flag == F2FS_GET_BLOCK_DIO &&
+ !f2fs_is_pinned_file(inode)))) {
+ if (unlikely(f2fs_cp_error(sbi)) ||
+ (f2fs_is_pinned_file(inode) && is_hole &&
+ flag != F2FS_GET_BLOCK_PRE_DIO)) {
err = -EIO;
goto sync_out;
}
@@ -3378,6 +3381,8 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,
f2fs_map_lock(sbi, flag);
locked = true;
} else if ((pos & PAGE_MASK) >= i_size_read(inode)) {
+ if (f2fs_is_pinned_file(inode))
+ return -EIO;
f2fs_map_lock(sbi, flag);
locked = true;
}
@@ -3414,8 +3419,15 @@ static int prepare_write_begin(struct f2fs_sb_info *sbi,

/* hole case */
err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
- if (!err && dn.data_blkaddr != NULL_ADDR)
- goto out;
+ if (!err) {
+ if (dn.data_blkaddr != NULL_ADDR) {
+ goto out;
+ } else if (f2fs_is_pinned_file(inode)) {
+ err = -EIO;
+ goto out;
+ }
+ }
+
f2fs_put_dnode(&dn);
f2fs_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO);
WARN_ON(flag != F2FS_GET_BLOCK_PRE_AIO);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 82277e95c88f..4db3b21c804b 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -57,7 +57,7 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
struct inode *inode = file_inode(vmf->vma->vm_file);
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
struct dnode_of_data dn;
- bool need_alloc = true;
+ bool need_alloc = !f2fs_is_pinned_file(inode);
int err = 0;
vm_fault_t ret;

@@ -114,19 +114,15 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault *vmf)
goto out_sem;
}

+ set_new_dnode(&dn, inode, NULL, NULL, 0);
if (need_alloc) {
/* block allocation */
- set_new_dnode(&dn, inode, NULL, NULL, 0);
err = f2fs_get_block_locked(&dn, page->index);
- }
-
-#ifdef CONFIG_F2FS_FS_COMPRESSION
- if (!need_alloc) {
- set_new_dnode(&dn, inode, NULL, NULL, 0);
+ } else {
err = f2fs_get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
f2fs_put_dnode(&dn);
}
-#endif
+
if (err) {
unlock_page(page);
goto out_sem;
@@ -4611,6 +4607,10 @@ static int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *iter,
return ret;
}

+ /* For pinned files, it should be fallocate()-ed in advance. */
+ if (f2fs_is_pinned_file(inode))
+ return 0;
+
/* Do not preallocate blocks that will be written partially in 4KB. */
map.m_lblk = F2FS_BLK_ALIGN(pos);
map.m_len = F2FS_BYTES_TO_BLK(pos + count);
--
2.44.0.396.g6e790dbe36-goog