Applications that create and extend and write to a file do not
expect to see 0 allocation size. When file is extended,
set its allocation size to a plausible value until we have a
chance to query the server for it. When the file is cached
this will prevent showing an impossible number of allocated
blocks (like 0). This fixes e.g. xfstests 614 which does
1) create a file and set its size to 64K
2) mmap write 64K to the file
3) stat -c %b for the file (to query the number of allocated blocks)
It was failing because we returned 0 blocks. Even though we would
return the correct cached file size, we returned an impossible
allocation size.
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
CC: <stable@xxxxxxxxxxxxxxx>
---
fs/cifs/inode.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 7c61bc9573c0..17a2c87b811c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -2395,7 +2395,7 @@ int cifs_getattr(struct user_namespace
*mnt_userns, const struct path *path,
* We need to be sure that all dirty pages are written and the server
* has actual ctime, mtime and file length.
*/
- if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_SIZE)) &&
+ if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_SIZE |
STATX_BLOCKS)) &&
!CIFS_CACHE_READ(CIFS_I(inode)) &&
inode->i_mapping && inode->i_mapping->nrpages != 0) {
rc = filemap_fdatawait(inode->i_mapping);
@@ -2585,6 +2585,14 @@ cifs_set_file_size(struct inode *inode, struct
iattr *attrs,
if (rc == 0) {
cifsInode->server_eof = attrs->ia_size;
cifs_setsize(inode, attrs->ia_size);
+ /*
+ * i_blocks is not related to (i_size / i_blksize),
+ * but instead 512 byte (2**9) size is required for
+ * calculating num blocks. Until we can query the
+ * server for actual allocation size, this is best estimate
+ * we have for the blocks allocated for this file
+ */
+ inode->i_blocks = (512 - 1 + attrs->ia_size) >> 9;
/*
* The man page of truncate says if the size changed,
@@ -2912,7 +2920,7 @@ cifs_setattr_nounix(struct dentry *direntry,
struct iattr *attrs)
sys_utimes in which case we ought to fail the call back to
the user when the server rejects the call */
if ((rc) && (attrs->ia_valid &
- (ATTR_MODE | ATTR_GID | ATTR_UID | ATTR_SIZE)))
+ (ATTR_MODE | ATTR_GID | ATTR_UID | ATTR_SIZE)))
rc = 0;
}
--
--
Thanks,
Steve
From 2ea7f44e54c7d3c4e8236e82950efb6aedda2486 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@xxxxxxxxxxxxx>
Date: Fri, 19 Mar 2021 00:05:48 -0500
Subject: [PATCH] cifs: fix allocation size on newly created files
Applications that create and extend and write to a file do not
expect to see 0 allocation size. When file is extended,
set its allocation size to a plausible value until we have a
chance to query the server for it. When the file is cached
this will prevent showing an impossible number of allocated
blocks (like 0). This fixes e.g. xfstests 614 which does
1) create a file and set its size to 64K
2) mmap write 64K to the file
3) stat -c %b for the file (to query the number of allocated blocks)
It was failing because we returned 0 blocks. Even though we would
return the correct cached file size, we returned an impossible
allocation size.
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
CC: <stable@xxxxxxxxxxxxxxx>
---
fs/cifs/inode.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 7c61bc9573c0..17a2c87b811c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -2395,7 +2395,7 @@ int cifs_getattr(struct user_namespace *mnt_userns, const struct path *path,
* We need to be sure that all dirty pages are written and the server
* has actual ctime, mtime and file length.
*/
- if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_SIZE)) &&
+ if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_SIZE | STATX_BLOCKS)) &&
!CIFS_CACHE_READ(CIFS_I(inode)) &&
inode->i_mapping && inode->i_mapping->nrpages != 0) {
rc = filemap_fdatawait(inode->i_mapping);
@@ -2585,6 +2585,14 @@ cifs_set_file_size(struct inode *inode, struct iattr *attrs,
if (rc == 0) {
cifsInode->server_eof = attrs->ia_size;
cifs_setsize(inode, attrs->ia_size);
+ /*
+ * i_blocks is not related to (i_size / i_blksize),
+ * but instead 512 byte (2**9) size is required for
+ * calculating num blocks. Until we can query the
+ * server for actual allocation size, this is best estimate
+ * we have for the blocks allocated for this file
+ */
+ inode->i_blocks = (512 - 1 + attrs->ia_size) >> 9;
/*
* The man page of truncate says if the size changed,
@@ -2912,7 +2920,7 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs)
sys_utimes in which case we ought to fail the call back to
the user when the server rejects the call */
if ((rc) && (attrs->ia_valid &
- (ATTR_MODE | ATTR_GID | ATTR_UID | ATTR_SIZE)))
+ (ATTR_MODE | ATTR_GID | ATTR_UID | ATTR_SIZE)))
rc = 0;
}
--
2.27.0
