From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: From: Amir Goldstein Subject: [PATCH v2 2/5] ovl: simplify ovl_same_sb() helper Date: Sun, 22 Dec 2019 10:07:56 +0200 Message-Id: <20191222080759.32035-3-amir73il@gmail.com> In-Reply-To: <20191222080759.32035-1-amir73il@gmail.com> References: <20191222080759.32035-1-amir73il@gmail.com> To: Miklos Szeredi Cc: linux-unionfs@vger.kernel.org List-ID: No code uses the sb returned from this helper, so make it retrun a boolean and rename it to ovl_same_fs(). The xino mode is irrelevant when all layers are on same fs, so instead of describing samefs with mode OVL_XINO_OFF, use a new mode OVL_XINO_SAME_FS, which is different than the case of non-samefs with xino=off. Create a new helper ovl_same_dev(), to use instead of the common check for (ovl_same_fs() || xinobits). Signed-off-by: Amir Goldstein --- fs/overlayfs/inode.c | 8 ++++---- fs/overlayfs/overlayfs.h | 21 ++++++++++++++++++++- fs/overlayfs/ovl_entry.h | 5 +++++ fs/overlayfs/readdir.c | 4 ++-- fs/overlayfs/super.c | 13 +++++-------- fs/overlayfs/util.c | 12 ------------ 6 files changed, 36 insertions(+), 27 deletions(-) diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 35712f54fdf9..b510e8408be3 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -78,7 +78,7 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr) static int ovl_map_dev_ino(struct dentry *dentry, struct kstat *stat, struct ovl_layer *lower_layer) { - bool samefs = ovl_same_sb(dentry->d_sb); + bool samefs = ovl_same_fs(dentry->d_sb); unsigned int xinobits = ovl_xino_bits(dentry->d_sb); if (samefs) { @@ -146,7 +146,7 @@ int ovl_getattr(const struct path *path, struct kstat *stat, struct path realpath; const struct cred *old_cred; bool is_dir = S_ISDIR(dentry->d_inode->i_mode); - bool samefs = ovl_same_sb(dentry->d_sb); + bool samefs = ovl_same_fs(dentry->d_sb); struct ovl_layer *lower_layer = NULL; int err; bool metacopy_blocks = false; @@ -168,7 +168,7 @@ int ovl_getattr(const struct path *path, struct kstat *stat, * If lower filesystem supports NFS file handles, this also guaranties * persistent st_ino across mount cycle. */ - if (!is_dir || samefs || ovl_xino_bits(dentry->d_sb)) { + if (!is_dir || ovl_same_dev(dentry->d_sb)) { if (!OVL_TYPE_UPPER(type)) { lower_layer = ovl_dentry_layer(dentry); } else if (OVL_TYPE_ORIGIN(type)) { @@ -586,7 +586,7 @@ static void ovl_fill_inode(struct inode *inode, umode_t mode, dev_t rdev, * ovl_new_inode(), ino arg is 0, so i_ino will be updated to real * upper inode i_ino on ovl_inode_init() or ovl_inode_update(). */ - if (ovl_same_sb(inode->i_sb) || xinobits) { + if (ovl_same_dev(inode->i_sb)) { inode->i_ino = ino; if (xinobits && fsid && !(ino >> (64 - xinobits))) inode->i_ino |= (unsigned long)fsid << (64 - xinobits); diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 50d41a314308..f7d01c06cdaf 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -45,6 +45,14 @@ enum ovl_entry_flag { OVL_E_CONNECTED, }; +enum { + OVL_XINO_OFF, + OVL_XINO_AUTO, + OVL_XINO_ON, + /* With samefs, xino is irrelevant */ + OVL_XINO_SAME_FS, +}; + /* * The tuple (fh,uuid) is a universal unique identifier for a copy up origin, * where: @@ -221,7 +229,6 @@ int ovl_want_write(struct dentry *dentry); void ovl_drop_write(struct dentry *dentry); struct dentry *ovl_workdir(struct dentry *dentry); const struct cred *ovl_override_creds(struct super_block *sb); -struct super_block *ovl_same_sb(struct super_block *sb); int ovl_can_decode_fh(struct super_block *sb); struct dentry *ovl_indexdir(struct super_block *sb); bool ovl_index_all(struct super_block *sb); @@ -306,6 +313,18 @@ static inline unsigned int ovl_xino_bits(struct super_block *sb) return ofs->xino_bits; } +/* All layers on same fs? */ +static inline bool ovl_same_fs(struct super_block *sb) +{ + return OVL_FS(sb)->config.xino == OVL_XINO_SAME_FS; +} + +/* All overlay inodes have same st_dev? */ +static inline bool ovl_same_dev(struct super_block *sb) +{ + return OVL_FS(sb)->config.xino != OVL_XINO_OFF; +} + static inline int ovl_inode_lock(struct inode *inode) { return mutex_lock_interruptible(&OVL_I(inode)->lock); diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h index ffaf7376f4ab..ef05817d8d89 100644 --- a/fs/overlayfs/ovl_entry.h +++ b/fs/overlayfs/ovl_entry.h @@ -75,6 +75,11 @@ struct ovl_fs { unsigned int xino_bits; }; +static inline struct ovl_fs *OVL_FS(struct super_block *sb) +{ + return (struct ovl_fs *)sb->s_fs_info; +} + /* private information held for every overlayfs dentry */ struct ovl_entry { union { diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index 32a7f8a38091..56f13e9ccbe6 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -469,7 +469,7 @@ static int ovl_cache_update_ino(struct path *path, struct ovl_cache_entry *p) int xinobits = ovl_xino_bits(dir->d_sb); int err = 0; - if (!ovl_same_sb(dir->d_sb) && !xinobits) + if (!ovl_same_dev(dir->d_sb)) goto out; if (p->name[0] == '.') { @@ -737,7 +737,7 @@ static int ovl_iterate(struct file *file, struct dir_context *ctx) * entries. */ if (ovl_xino_bits(dentry->d_sb) || - (ovl_same_sb(dentry->d_sb) && + (ovl_same_fs(dentry->d_sb) && (ovl_is_impure_dir(file) || OVL_TYPE_MERGE(ovl_path_type(dentry->d_parent))))) { return ovl_iterate_real(file, ctx); diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 84f96f64bbb8..2d03ab26e202 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -316,12 +316,6 @@ static const char *ovl_redirect_mode_def(void) return ovl_redirect_dir_def ? "on" : "off"; } -enum { - OVL_XINO_OFF, - OVL_XINO_AUTO, - OVL_XINO_ON, -}; - static const char * const ovl_xino_str[] = { "off", "auto", @@ -358,7 +352,8 @@ static int ovl_show_options(struct seq_file *m, struct dentry *dentry) if (ofs->config.nfs_export != ovl_nfs_export_def) seq_printf(m, ",nfs_export=%s", ofs->config.nfs_export ? "on" : "off"); - if (ofs->config.xino != ovl_xino_def()) + if (ofs->config.xino != ovl_xino_def() && + ofs->config.xino != OVL_XINO_SAME_FS) seq_printf(m, ",xino=%s", ovl_xino_str[ofs->config.xino]); if (ofs->config.metacopy != ovl_metacopy_def) seq_printf(m, ",metacopy=%s", @@ -1393,8 +1388,10 @@ static int ovl_get_layers(struct super_block *sb, struct ovl_fs *ofs, * inode number. */ if (!ofs->numlowerfs || (ofs->numlowerfs == 1 && !ofs->upper_mnt)) { + if (ofs->config.xino == OVL_XINO_ON) + pr_info("overlayfs: \"xino=on\" is useless with all layers on same fs, ignore.\n"); ofs->xino_bits = 0; - ofs->config.xino = OVL_XINO_OFF; + ofs->config.xino = OVL_XINO_SAME_FS; } else if (ofs->config.xino == OVL_XINO_ON && !ofs->xino_bits) { /* * This is a roundup of number of bits needed for numlowerfs+1 diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index 3fa1ca8ddd48..256f166b4a17 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -40,18 +40,6 @@ const struct cred *ovl_override_creds(struct super_block *sb) return override_creds(ofs->creator_cred); } -struct super_block *ovl_same_sb(struct super_block *sb) -{ - struct ovl_fs *ofs = sb->s_fs_info; - - if (!ofs->numlowerfs) - return ofs->upper_mnt->mnt_sb; - else if (ofs->numlowerfs == 1 && !ofs->upper_mnt) - return ofs->lower_fs[0].sb; - else - return NULL; -} - /* * Check if underlying fs supports file handles and try to determine encoding * type, in order to deduce maximum inode number used by fs. -- 2.17.1