From 046aca3c25fd28da591f59a2dc1a01848e81e0b2 Mon Sep 17 00:00:00 2001 From: "Paulo Alcantara (SUSE)" Date: Wed, 18 Dec 2019 18:11:37 -0300 Subject: [PATCH] cifs: Optimize readdir on reparse points When listing a directory with thounsands of files and most of them are reparse points, we simply marked all those dentries for revalidation and then sending additional (compounded) create/getinfo/close requests for each of them. Instead, upon receiving a response from an SMB2_QUERY_DIRECTORY (FileIdFullDirectoryInformation) command, the directory entries that have a file attribute of FILE_ATTRIBUTE_REPARSE_POINT will contain an EaSize field with a reparse tag in it, so we parse it and mark the dentry for revalidation only if it is a DFS or a symlink. Signed-off-by: Paulo Alcantara (SUSE) Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/cifsglob.h | 1 + fs/cifs/readdir.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 55 insertions(+), 9 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index ce9bac7..40705e8 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1693,6 +1693,7 @@ struct cifs_fattr { struct timespec64 cf_atime; struct timespec64 cf_mtime; struct timespec64 cf_ctime; + u32 cf_cifstag; }; static inline void free_dfs_info_param(struct dfs_info3_param *param) diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c index 3925a7b..d17587c 100644 --- a/fs/cifs/readdir.c +++ b/fs/cifs/readdir.c @@ -139,6 +139,28 @@ retry: dput(dentry); } +static bool reparse_file_needs_reval(const struct cifs_fattr *fattr) +{ + if (!(fattr->cf_cifsattrs & ATTR_REPARSE)) + return false; + /* + * The DFS tags should be only intepreted by server side as per + * MS-FSCC 2.1.2.1, but let's include them anyway. + * + * Besides, if cf_cifstag is unset (0), then we still need it to be + * revalidated to know exactly what reparse point it is. + */ + switch (fattr->cf_cifstag) { + case IO_REPARSE_TAG_DFS: + case IO_REPARSE_TAG_DFSR: + case IO_REPARSE_TAG_SYMLINK: + case IO_REPARSE_TAG_NFS: + case 0: + return true; + } + return false; +} + static void cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) { @@ -158,7 +180,7 @@ cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) * is a symbolic link, DFS referral or a reparse point with a direct * access like junctions, deduplicated files, NFS symlinks. */ - if (fattr->cf_cifsattrs & ATTR_REPARSE) + if (reparse_file_needs_reval(fattr)) fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; /* non-unix readdir doesn't provide nlink */ @@ -194,19 +216,37 @@ cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) } } +static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info) +{ + const FILE_DIRECTORY_INFO *fi = info; + + memset(fattr, 0, sizeof(*fattr)); + fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes); + fattr->cf_eof = le64_to_cpu(fi->EndOfFile); + fattr->cf_bytes = le64_to_cpu(fi->AllocationSize); + fattr->cf_createtime = le64_to_cpu(fi->CreationTime); + fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime); + fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime); + fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime); +} + void cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info, struct cifs_sb_info *cifs_sb) { - memset(fattr, 0, sizeof(*fattr)); - fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes); - fattr->cf_eof = le64_to_cpu(info->EndOfFile); - fattr->cf_bytes = le64_to_cpu(info->AllocationSize); - fattr->cf_createtime = le64_to_cpu(info->CreationTime); - fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime); - fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime); - fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime); + __dir_info_to_fattr(fattr, info); + cifs_fill_common_info(fattr, cifs_sb); +} +static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr, + SEARCH_ID_FULL_DIR_INFO *info, + struct cifs_sb_info *cifs_sb) +{ + __dir_info_to_fattr(fattr, info); + + /* See MS-FSCC 2.4.18 FileIdFullDirectoryInformation */ + if (fattr->cf_cifsattrs & ATTR_REPARSE) + fattr->cf_cifstag = le32_to_cpu(info->EaSize); cifs_fill_common_info(fattr, cifs_sb); } @@ -755,6 +795,11 @@ static int cifs_filldir(char *find_entry, struct file *file, (FIND_FILE_STANDARD_INFO *)find_entry, cifs_sb); break; + case SMB_FIND_FILE_ID_FULL_DIR_INFO: + cifs_fulldir_info_to_fattr(&fattr, + (SEARCH_ID_FULL_DIR_INFO *)find_entry, + cifs_sb); + break; default: cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)find_entry, -- 2.7.4