On Wed, 18 Sep 2013 16:00:17 -0700
Jim McDonough <jmcd@xxxxxxxxx> wrote:
> One more try . Trying to not trust non-unix servers when they are
> reporting zero without delete pending, or in the directory case, on
> querypathinfo, and never on readdir. But only faking it on inode
> instantiation.
>
> Also, this is finally for a recent kernel...
>
>
> --
> fs/cifs/cifsglob.h | 1 +
> fs/cifs/inode.c | 41 +++++++++++++++++++++++++++++++++++------
> fs/cifs/readdir.c | 3 +++
> 3 files changed, 39 insertions(+), 6 deletions(-)
>
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 52ca861..750dbfa 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -1253,6 +1253,7 @@ struct dfs_info3_param {
> #define CIFS_FATTR_DELETE_PENDING 0x2
> #define CIFS_FATTR_NEED_REVAL 0x4
> #define CIFS_FATTR_INO_COLLISION 0x8
> +#define CIFS_FATTR_UNKNOWN_NLINK 0x10
>
> struct cifs_fattr {
> u32 cf_flags;
> diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
> index 449b6cf..1d7bbb9 100644
> --- a/fs/cifs/inode.c
> +++ b/fs/cifs/inode.c
> @@ -120,6 +120,30 @@ cifs_revalidate_cache(struct inode *inode, struct
> cifs_fattr *fattr)
> cifs_i->invalid_mapping = true;
> }
>
> +/* copy nlink to the inode, unless it wasn't provided. Provide
> + sane values if we don't have an existing one and none was provided */
> +static void
> +cifs_nlink_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
> +{
> + /* if we're in a situation where we can't trust what we
> + got from the server (readdir, some non-unix cases)
> + fake reasonable values
> + */
Nit: best to use kernel-style comments. Also, this patch appears to be
whitespace-damaged.
> + if (fattr->cf_flags & CIFS_FATTR_UNKNOWN_NLINK) {
> + /* only provide fake values on a new inode */
> + if (inode->i_state & I_NEW) {
> + if (fattr->cf_cifsattrs & ATTR_DIRECTORY)
> + set_nlink(inode, 2);
> + else
> + set_nlink(inode, 1);
> + }
> + return;
> + }
> +
> + /* we trust the server, so update it */
> + set_nlink(inode, fattr->cf_nlink);
> +}
> +
> /* populate an inode with info from a cifs_fattr struct */
> void
> cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
> @@ -134,7 +158,7 @@ cifs_fattr_to_inode(struct inode *inode, struct
> cifs_fattr *fattr)
> inode->i_mtime = fattr->cf_mtime;
> inode->i_ctime = fattr->cf_ctime;
> inode->i_rdev = fattr->cf_rdev;
> - set_nlink(inode, fattr->cf_nlink);
> + cifs_nlink_fattr_to_inode(inode, fattr);
> inode->i_uid = fattr->cf_uid;
> inode->i_gid = fattr->cf_gid;
>
> @@ -541,6 +565,7 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr,
> FILE_ALL_INFO *info,
> fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
> fattr->cf_createtime = le64_to_cpu(info->CreationTime);
>
> + fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
> if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
> fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
> fattr->cf_dtype = DT_DIR;
> @@ -548,7 +573,8 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr,
> FILE_ALL_INFO *info,
> * Server can return wrong NumberOfLinks value for directories
> * when Unix extensions are disabled - fake it.
> */
> - fattr->cf_nlink = 2;
> + if (!tcon->unix_ext)
> + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
> } else {
> fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
> fattr->cf_dtype = DT_REG;
> @@ -557,11 +583,14 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr,
> FILE_ALL_INFO *info,
> if (fattr->cf_cifsattrs & ATTR_READONLY)
> fattr->cf_mode &= ~(S_IWUGO);
>
> - fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
> - if (fattr->cf_nlink < 1) {
> - cifs_dbg(1, "replacing bogus file nlink value %u\n",
> + /* Don't accept zero nlink from non-unix servers unless
> + delete is pending. Instead mark it as unknown.
> + */
> + if ((fattr->cf_nlink < 1) && (!tcon->unix_ext) &&
> + (!info->DeletePending)) {
Probably don't need all of the extra parens in the above conditional,
and the indentation below looks funny. Some of that might be the
tabs-to-spaces conversion that seems to have occured here though.
> + cifs_dbg(1, "bogus file nlink value %u\n",
> fattr->cf_nlink);
> - fattr->cf_nlink = 1;
> + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
> }
> }
>
> diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
> index 69d2c82..b1f67dc 100644
> --- a/fs/cifs/readdir.c
> +++ b/fs/cifs/readdir.c
> @@ -177,6 +177,9 @@ cifs_fill_common_info(struct cifs_fattr *fattr,
> struct cifs_sb_info *cifs_sb)
> fattr->cf_dtype = DT_REG;
> }
>
> + /* non-unix readdir doesn't provide nlink */
> + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
> +
> if (fattr->cf_cifsattrs & ATTR_READONLY)
> fattr->cf_mode &= ~S_IWUGO;
>
Nice work! The logic looks correct. It just needs a little bit of style
cleanup and to be sent in a way that hasn't converted tabs to spaces.
You can add this to the final patch:
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
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