cephfs can benefit from statx. We can have the client just request caps sufficient for the needed attributes and leave off the rest. Also, recognize when AT_STATX_DONT_SYNC is set, and just scrape the inode without doing any call in that case. Force a call to the MDS in the event that AT_STATX_FORCE_SYNC is set. Link: http://tracker.ceph.com/issues/39258 Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/ceph/inode.c | 85 +++++++++++++++++++++++++++++++++---------------- 1 file changed, 57 insertions(+), 28 deletions(-) v2: eliminate a goto, clean up comments, add Link: to changelog diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 2d61ddda9bf5..b33ba16f7ae8 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -2255,43 +2255,72 @@ int ceph_permission(struct inode *inode, int mask) return err; } +/* Craft a mask of needed caps given a set of requested statx attrs. */ +static int statx_to_caps(u32 want) +{ + int mask = 0; + + if (want & (STATX_MODE|STATX_UID|STATX_GID|STATX_CTIME)) + mask |= CEPH_CAP_AUTH_SHARED; + + if (want & (STATX_NLINK|STATX_CTIME)) + mask |= CEPH_CAP_LINK_SHARED; + + if (want & (STATX_ATIME|STATX_MTIME|STATX_CTIME|STATX_SIZE| + STATX_BLOCKS)) + mask |= CEPH_CAP_FILE_SHARED; + + if (want & (STATX_CTIME)) + mask |= CEPH_CAP_XATTR_SHARED; + + return mask; +} + /* - * Get all attributes. Hopefully somedata we'll have a statlite() - * and can limit the fields we require to be accurate. + * Get all the attributes. If we have sufficient caps for the requested attrs, + * then we can avoid talking to the MDS at all. */ int ceph_getattr(const struct path *path, struct kstat *stat, u32 request_mask, unsigned int flags) { struct inode *inode = d_inode(path->dentry); struct ceph_inode_info *ci = ceph_inode(inode); - int err; + int err = 0; - err = ceph_do_getattr(inode, CEPH_STAT_CAP_INODE_ALL, false); - if (!err) { - generic_fillattr(inode, stat); - stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino); - if (ceph_snap(inode) == CEPH_NOSNAP) - stat->dev = inode->i_sb->s_dev; + /* Skip the getattr altogether if we're asked not to sync */ + if (!(flags & AT_STATX_DONT_SYNC)) { + err = ceph_do_getattr(inode, statx_to_caps(request_mask), + flags & AT_STATX_FORCE_SYNC); + if (err) + return err; + } + + generic_fillattr(inode, stat); + stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino); + if (ceph_snap(inode) == CEPH_NOSNAP) + stat->dev = inode->i_sb->s_dev; + else + stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0; + + if (S_ISDIR(inode->i_mode)) { + if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), + RBYTES)) + stat->size = ci->i_rbytes; else - stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0; - - if (S_ISDIR(inode->i_mode)) { - if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), - RBYTES)) - stat->size = ci->i_rbytes; - else - stat->size = ci->i_files + ci->i_subdirs; - stat->blocks = 0; - stat->blksize = 65536; - /* - * Some applications rely on the number of st_nlink - * value on directories to be either 0 (if unlinked) - * or 2 + number of subdirectories. - */ - if (stat->nlink == 1) - /* '.' + '..' + subdirs */ - stat->nlink = 1 + 1 + ci->i_subdirs; - } + stat->size = ci->i_files + ci->i_subdirs; + stat->blocks = 0; + stat->blksize = 65536; + /* + * Some applications rely on the number of st_nlink + * value on directories to be either 0 (if unlinked) + * or 2 + number of subdirectories. + */ + if (stat->nlink == 1) + /* '.' + '..' + subdirs */ + stat->nlink = 1 + 1 + ci->i_subdirs; } + + /* Mask off any higher bits (e.g. btime) until we have support */ + stat->result_mask = request_mask & STATX_BASIC_STATS; return err; } -- 2.20.1
