summaryrefslogtreecommitdiff
path: root/fs/overlayfs/super.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/overlayfs/super.c')
-rw-r--r--fs/overlayfs/super.c58
1 files changed, 44 insertions, 14 deletions
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index f42c9407f..619ad4b01 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -16,6 +16,7 @@
#include <linux/slab.h>
#include <linux/parser.h>
#include <linux/module.h>
+#include <linux/pagemap.h>
#include <linux/sched.h>
#include <linux/statfs.h>
#include <linux/seq_file.h>
@@ -25,12 +26,11 @@ MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
MODULE_DESCRIPTION("Overlay filesystem");
MODULE_LICENSE("GPL");
-#define OVERLAYFS_SUPER_MAGIC 0x794c7630
-
struct ovl_config {
char *lowerdir;
char *upperdir;
char *workdir;
+ bool default_permissions;
};
/* private information held for overlayfs's superblock */
@@ -76,12 +76,14 @@ enum ovl_path_type ovl_path_type(struct dentry *dentry)
if (oe->__upperdentry) {
type = __OVL_PATH_UPPER;
- if (oe->numlower) {
- if (S_ISDIR(dentry->d_inode->i_mode))
- type |= __OVL_PATH_MERGE;
- } else if (!oe->opaque) {
+ /*
+ * Non-dir dentry can hold lower dentry from previous
+ * location. Its purity depends only on opaque flag.
+ */
+ if (oe->numlower && S_ISDIR(dentry->d_inode->i_mode))
+ type |= __OVL_PATH_MERGE;
+ else if (!oe->opaque)
type |= __OVL_PATH_PURE;
- }
} else {
if (oe->numlower > 1)
type |= __OVL_PATH_MERGE;
@@ -155,6 +157,18 @@ struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper)
return realdentry;
}
+struct vfsmount *ovl_entry_mnt_real(struct ovl_entry *oe, struct inode *inode,
+ bool is_upper)
+{
+ if (is_upper) {
+ struct ovl_fs *ofs = inode->i_sb->s_fs_info;
+
+ return ofs->upper_mnt;
+ } else {
+ return oe->numlower ? oe->lowerstack[0].mnt : NULL;
+ }
+}
+
struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
@@ -162,6 +176,13 @@ struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry)
return oe->cache;
}
+bool ovl_is_default_permissions(struct inode *inode)
+{
+ struct ovl_fs *ofs = inode->i_sb->s_fs_info;
+
+ return ofs->config.default_permissions;
+}
+
void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache)
{
struct ovl_entry *oe = dentry->d_fsdata;
@@ -210,7 +231,7 @@ void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
- WARN_ON(!mutex_is_locked(&upperdentry->d_parent->d_inode->i_mutex));
+ WARN_ON(!inode_is_locked(upperdentry->d_parent->d_inode));
WARN_ON(oe->__upperdentry);
BUG_ON(!upperdentry->d_inode);
/*
@@ -225,7 +246,7 @@ void ovl_dentry_version_inc(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
- WARN_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
+ WARN_ON(!inode_is_locked(dentry->d_inode));
oe->version++;
}
@@ -233,7 +254,7 @@ u64 ovl_dentry_version_get(struct dentry *dentry)
{
struct ovl_entry *oe = dentry->d_fsdata;
- WARN_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
+ WARN_ON(!inode_is_locked(dentry->d_inode));
return oe->version;
}
@@ -322,6 +343,7 @@ static const struct dentry_operations ovl_dentry_operations = {
static const struct dentry_operations ovl_reval_dentry_operations = {
.d_release = ovl_dentry_release,
+ .d_select_inode = ovl_d_select_inode,
.d_revalidate = ovl_dentry_revalidate,
.d_weak_revalidate = ovl_dentry_weak_revalidate,
};
@@ -356,9 +378,9 @@ static inline struct dentry *ovl_lookup_real(struct dentry *dir,
{
struct dentry *dentry;
- mutex_lock(&dir->d_inode->i_mutex);
+ inode_lock(dir->d_inode);
dentry = lookup_one_len(name->name, dir, name->len);
- mutex_unlock(&dir->d_inode->i_mutex);
+ inode_unlock(dir->d_inode);
if (IS_ERR(dentry)) {
if (PTR_ERR(dentry) == -ENOENT)
@@ -595,6 +617,8 @@ static int ovl_show_options(struct seq_file *m, struct dentry *dentry)
seq_show_option(m, "upperdir", ufs->config.upperdir);
seq_show_option(m, "workdir", ufs->config.workdir);
}
+ if (ufs->config.default_permissions)
+ seq_puts(m, ",default_permissions");
return 0;
}
@@ -619,6 +643,7 @@ enum {
OPT_LOWERDIR,
OPT_UPPERDIR,
OPT_WORKDIR,
+ OPT_DEFAULT_PERMISSIONS,
OPT_ERR,
};
@@ -626,6 +651,7 @@ static const match_table_t ovl_tokens = {
{OPT_LOWERDIR, "lowerdir=%s"},
{OPT_UPPERDIR, "upperdir=%s"},
{OPT_WORKDIR, "workdir=%s"},
+ {OPT_DEFAULT_PERMISSIONS, "default_permissions"},
{OPT_ERR, NULL}
};
@@ -686,6 +712,10 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config)
return -ENOMEM;
break;
+ case OPT_DEFAULT_PERMISSIONS:
+ config->default_permissions = true;
+ break;
+
default:
pr_err("overlayfs: unrecognized mount option \"%s\" or missing value\n", p);
return -EINVAL;
@@ -717,7 +747,7 @@ static struct dentry *ovl_workdir_create(struct vfsmount *mnt,
if (err)
return ERR_PTR(err);
- mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
+ inode_lock_nested(dir, I_MUTEX_PARENT);
retry:
work = lookup_one_len(OVL_WORKDIR_NAME, dentry,
strlen(OVL_WORKDIR_NAME));
@@ -743,7 +773,7 @@ retry:
goto out_dput;
}
out_unlock:
- mutex_unlock(&dir->i_mutex);
+ inode_unlock(dir);
mnt_drop_write(mnt);
return work;