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-rw-r--r--fs/kernfs/dir.c1
-rw-r--r--fs/kernfs/file.c58
-rw-r--r--fs/kernfs/kernfs-internal.h5
-rw-r--r--fs/kernfs/mount.c22
4 files changed, 68 insertions, 18 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index ac127cd008bf..a693f5b01ae6 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -714,6 +714,7 @@ struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
return ERR_PTR(-ENOMEM);
ida_init(&root->ino_ida);
+ INIT_LIST_HEAD(&root->supers);
kn = __kernfs_new_node(root, "", S_IFDIR | S_IRUGO | S_IXUGO,
KERNFS_DIR);
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index e01ea4a14a01..e3d37f607f97 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -14,6 +14,7 @@
#include <linux/poll.h>
#include <linux/pagemap.h>
#include <linux/sched.h>
+#include <linux/fsnotify.h>
#include "kernfs-internal.h"
@@ -610,6 +611,7 @@ static void kernfs_put_open_node(struct kernfs_node *kn,
static int kernfs_fop_open(struct inode *inode, struct file *file)
{
struct kernfs_node *kn = file->f_path.dentry->d_fsdata;
+ struct kernfs_root *root = kernfs_root(kn);
const struct kernfs_ops *ops;
struct kernfs_open_file *of;
bool has_read, has_write, has_mmap;
@@ -624,14 +626,16 @@ static int kernfs_fop_open(struct inode *inode, struct file *file)
has_write = ops->write || ops->mmap;
has_mmap = ops->mmap;
- /* check perms and supported operations */
- if ((file->f_mode & FMODE_WRITE) &&
- (!(inode->i_mode & S_IWUGO) || !has_write))
- goto err_out;
+ /* see the flag definition for details */
+ if (root->flags & KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK) {
+ if ((file->f_mode & FMODE_WRITE) &&
+ (!(inode->i_mode & S_IWUGO) || !has_write))
+ goto err_out;
- if ((file->f_mode & FMODE_READ) &&
- (!(inode->i_mode & S_IRUGO) || !has_read))
- goto err_out;
+ if ((file->f_mode & FMODE_READ) &&
+ (!(inode->i_mode & S_IRUGO) || !has_read))
+ goto err_out;
+ }
/* allocate a kernfs_open_file for the file */
error = -ENOMEM;
@@ -787,20 +791,48 @@ static unsigned int kernfs_fop_poll(struct file *filp, poll_table *wait)
*/
void kernfs_notify(struct kernfs_node *kn)
{
+ struct kernfs_root *root = kernfs_root(kn);
struct kernfs_open_node *on;
+ struct kernfs_super_info *info;
unsigned long flags;
+ if (WARN_ON(kernfs_type(kn) != KERNFS_FILE))
+ return;
+
+ /* kick poll */
spin_lock_irqsave(&kernfs_open_node_lock, flags);
- if (!WARN_ON(kernfs_type(kn) != KERNFS_FILE)) {
- on = kn->attr.open;
- if (on) {
- atomic_inc(&on->event);
- wake_up_interruptible(&on->poll);
- }
+ on = kn->attr.open;
+ if (on) {
+ atomic_inc(&on->event);
+ wake_up_interruptible(&on->poll);
}
spin_unlock_irqrestore(&kernfs_open_node_lock, flags);
+
+ /* kick fsnotify */
+ mutex_lock(&kernfs_mutex);
+
+ list_for_each_entry(info, &root->supers, node) {
+ struct inode *inode;
+ struct dentry *dentry;
+
+ inode = ilookup(info->sb, kn->ino);
+ if (!inode)
+ continue;
+
+ dentry = d_find_any_alias(inode);
+ if (dentry) {
+ fsnotify_parent(NULL, dentry, FS_MODIFY);
+ fsnotify(inode, FS_MODIFY, inode, FSNOTIFY_EVENT_INODE,
+ NULL, 0);
+ dput(dentry);
+ }
+
+ iput(inode);
+ }
+
+ mutex_unlock(&kernfs_mutex);
}
EXPORT_SYMBOL_GPL(kernfs_notify);
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 8be13b2a079b..dc84a3ef9ca2 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -49,6 +49,8 @@ static inline struct kernfs_root *kernfs_root(struct kernfs_node *kn)
* mount.c
*/
struct kernfs_super_info {
+ struct super_block *sb;
+
/*
* The root associated with this super_block. Each super_block is
* identified by the root and ns it's associated with.
@@ -62,6 +64,9 @@ struct kernfs_super_info {
* an array and compare kernfs_node tag against every entry.
*/
const void *ns;
+
+ /* anchored at kernfs_root->supers, protected by kernfs_mutex */
+ struct list_head node;
};
#define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info))
diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
index 6a5f04ac8704..d171b98a6cdd 100644
--- a/fs/kernfs/mount.c
+++ b/fs/kernfs/mount.c
@@ -62,15 +62,16 @@ struct kernfs_root *kernfs_root_from_sb(struct super_block *sb)
return NULL;
}
-static int kernfs_fill_super(struct super_block *sb)
+static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
{
struct kernfs_super_info *info = kernfs_info(sb);
struct inode *inode;
struct dentry *root;
+ info->sb = sb;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
- sb->s_magic = SYSFS_MAGIC;
+ sb->s_magic = magic;
sb->s_op = &kernfs_sops;
sb->s_time_gran = 1;
@@ -131,6 +132,7 @@ const void *kernfs_super_ns(struct super_block *sb)
* @fs_type: file_system_type of the fs being mounted
* @flags: mount flags specified for the mount
* @root: kernfs_root of the hierarchy being mounted
+ * @magic: file system specific magic number
* @new_sb_created: tell the caller if we allocated a new superblock
* @ns: optional namespace tag of the mount
*
@@ -142,8 +144,8 @@ const void *kernfs_super_ns(struct super_block *sb)
* The return value can be passed to the vfs layer verbatim.
*/
struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, bool *new_sb_created,
- const void *ns)
+ struct kernfs_root *root, unsigned long magic,
+ bool *new_sb_created, const void *ns)
{
struct super_block *sb;
struct kernfs_super_info *info;
@@ -166,12 +168,18 @@ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
*new_sb_created = !sb->s_root;
if (!sb->s_root) {
- error = kernfs_fill_super(sb);
+ struct kernfs_super_info *info = kernfs_info(sb);
+
+ error = kernfs_fill_super(sb, magic);
if (error) {
deactivate_locked_super(sb);
return ERR_PTR(error);
}
sb->s_flags |= MS_ACTIVE;
+
+ mutex_lock(&kernfs_mutex);
+ list_add(&info->node, &root->supers);
+ mutex_unlock(&kernfs_mutex);
}
return dget(sb->s_root);
@@ -190,6 +198,10 @@ void kernfs_kill_sb(struct super_block *sb)
struct kernfs_super_info *info = kernfs_info(sb);
struct kernfs_node *root_kn = sb->s_root->d_fsdata;
+ mutex_lock(&kernfs_mutex);
+ list_del(&info->node);
+ mutex_unlock(&kernfs_mutex);
+
/*
* Remove the superblock from fs_supers/s_instances
* so we can't find it, before freeing kernfs_super_info.
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 04:01:48 +0100