We report the block size properly (typically much larger) - but the kernel API returns allocation size in 512 byte units no matter what the block size is. Number of blocks returned for the kernel API inode->i_blocks is unrelated to the block size (simply allocation_size/512 rounded up by 1). On Fri, Mar 19, 2021 at 12:38 PM Tom Talpey <tom@xxxxxxxxxx> wrote: > > On 3/19/2021 1:25 AM, Steve French wrote: > > 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; > > I don't think 512 is a very robust choice, no server uses anything > so small any more. MS-FSA requires the allocation quantum to be the > volume cluster size. Is that value available locally? > > Tom. > > > /* > > * 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