summaryrefslogtreecommitdiff
path: root/fs/debugfs/inode.c
diff options
context:
space:
mode:
authorJiri Kosina <jkosina@suse.com>2025-03-26 13:42:07 +0100
committerJiri Kosina <jkosina@suse.com>2025-03-26 13:42:07 +0100
commitb3cc7428a32202936904b5b07cf9f135025bafd6 (patch)
treed4a1a6180ac5939fccd92acd6f8d7d1388575c4a /fs/debugfs/inode.c
parentdb52926fb0be40e1d588a346df73f5ea3a34a4c6 (diff)
parent01601fdd40ecf4467c8ae4d215dbb7d2a0599a2c (diff)
Merge branch 'for-6.15/amd_sfh' into for-linus
From: Mario Limonciello <mario.limonciello@amd.com> Some platforms include a human presence detection (HPD) sensor. When enabled and a user is detected a wake event will be emitted from the sensor fusion hub that software can react to. Example use cases are "wake from suspend on approach" or to "lock when leaving". This is currently enabled by default on supported systems, but users can't control it. This essentially means that wake on approach is enabled which is a really surprising behavior to users that don't expect it. Instead of defaulting to enabled add a sysfs knob that users can use to enable the feature if desirable and set it to disabled by default.
Diffstat (limited to 'fs/debugfs/inode.c')
-rw-r--r--fs/debugfs/inode.c208
1 files changed, 104 insertions, 104 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index e752009de9292..75715d8877eed 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -208,16 +208,34 @@ static int debugfs_show_options(struct seq_file *m, struct dentry *root)
return 0;
}
+static struct kmem_cache *debugfs_inode_cachep __ro_after_init;
+
+static void init_once(void *foo)
+{
+ struct debugfs_inode_info *info = foo;
+ inode_init_once(&info->vfs_inode);
+}
+
+static struct inode *debugfs_alloc_inode(struct super_block *sb)
+{
+ struct debugfs_inode_info *info;
+ info = alloc_inode_sb(sb, debugfs_inode_cachep, GFP_KERNEL);
+ if (!info)
+ return NULL;
+ return &info->vfs_inode;
+}
+
static void debugfs_free_inode(struct inode *inode)
{
if (S_ISLNK(inode->i_mode))
kfree(inode->i_link);
- free_inode_nonrcu(inode);
+ kmem_cache_free(debugfs_inode_cachep, DEBUGFS_I(inode));
}
static const struct super_operations debugfs_super_operations = {
.statfs = simple_statfs,
.show_options = debugfs_show_options,
+ .alloc_inode = debugfs_alloc_inode,
.free_inode = debugfs_free_inode,
};
@@ -225,23 +243,18 @@ static void debugfs_release_dentry(struct dentry *dentry)
{
struct debugfs_fsdata *fsd = dentry->d_fsdata;
- if ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT)
- return;
-
- /* check it wasn't a dir (no fsdata) or automount (no real_fops) */
- if (fsd && (fsd->real_fops || fsd->short_fops)) {
+ if (fsd) {
WARN_ON(!list_empty(&fsd->cancellations));
mutex_destroy(&fsd->cancellations_mtx);
}
-
kfree(fsd);
}
static struct vfsmount *debugfs_automount(struct path *path)
{
- struct debugfs_fsdata *fsd = path->dentry->d_fsdata;
+ struct inode *inode = path->dentry->d_inode;
- return fsd->automount(path->dentry, d_inode(path->dentry)->i_private);
+ return DEBUGFS_I(inode)->automount(path->dentry, inode->i_private);
}
static const struct dentry_operations debugfs_dops = {
@@ -411,6 +424,7 @@ static struct dentry *end_creating(struct dentry *dentry)
static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
struct dentry *parent, void *data,
+ const void *aux,
const struct file_operations *proxy_fops,
const void *real_fops)
{
@@ -441,9 +455,11 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
inode->i_private = data;
inode->i_op = &debugfs_file_inode_operations;
+ if (!real_fops)
+ proxy_fops = &debugfs_noop_file_operations;
inode->i_fop = proxy_fops;
- dentry->d_fsdata = (void *)((unsigned long)real_fops |
- DEBUGFS_FSDATA_IS_REAL_FOPS_BIT);
+ DEBUGFS_I(inode)->raw = real_fops;
+ DEBUGFS_I(inode)->aux = aux;
d_instantiate(dentry, inode);
fsnotify_create(d_inode(dentry->d_parent), dentry);
@@ -452,30 +468,22 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode,
struct dentry *debugfs_create_file_full(const char *name, umode_t mode,
struct dentry *parent, void *data,
+ const void *aux,
const struct file_operations *fops)
{
- if (WARN_ON((unsigned long)fops &
- DEBUGFS_FSDATA_IS_REAL_FOPS_BIT))
- return ERR_PTR(-EINVAL);
-
- return __debugfs_create_file(name, mode, parent, data,
- fops ? &debugfs_full_proxy_file_operations :
- &debugfs_noop_file_operations,
+ return __debugfs_create_file(name, mode, parent, data, aux,
+ &debugfs_full_proxy_file_operations,
fops);
}
EXPORT_SYMBOL_GPL(debugfs_create_file_full);
struct dentry *debugfs_create_file_short(const char *name, umode_t mode,
- struct dentry *parent, void *data,
- const struct debugfs_short_fops *fops)
+ struct dentry *parent, void *data,
+ const void *aux,
+ const struct debugfs_short_fops *fops)
{
- if (WARN_ON((unsigned long)fops &
- DEBUGFS_FSDATA_IS_REAL_FOPS_BIT))
- return ERR_PTR(-EINVAL);
-
- return __debugfs_create_file(name, mode, parent, data,
- fops ? &debugfs_full_short_proxy_file_operations :
- &debugfs_noop_file_operations,
+ return __debugfs_create_file(name, mode, parent, data, aux,
+ &debugfs_full_short_proxy_file_operations,
fops);
}
EXPORT_SYMBOL_GPL(debugfs_create_file_short);
@@ -512,9 +520,8 @@ struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
const struct file_operations *fops)
{
- return __debugfs_create_file(name, mode, parent, data,
- fops ? &debugfs_open_proxy_file_operations :
- &debugfs_noop_file_operations,
+ return __debugfs_create_file(name, mode, parent, data, NULL,
+ &debugfs_open_proxy_file_operations,
fops);
}
EXPORT_SYMBOL_GPL(debugfs_create_file_unsafe);
@@ -624,23 +631,13 @@ struct dentry *debugfs_create_automount(const char *name,
void *data)
{
struct dentry *dentry = start_creating(name, parent);
- struct debugfs_fsdata *fsd;
struct inode *inode;
if (IS_ERR(dentry))
return dentry;
- fsd = kzalloc(sizeof(*fsd), GFP_KERNEL);
- if (!fsd) {
- failed_creating(dentry);
- return ERR_PTR(-ENOMEM);
- }
-
- fsd->automount = f;
-
if (!(debugfs_allow & DEBUGFS_ALLOW_API)) {
failed_creating(dentry);
- kfree(fsd);
return ERR_PTR(-EPERM);
}
@@ -648,14 +645,13 @@ struct dentry *debugfs_create_automount(const char *name,
if (unlikely(!inode)) {
pr_err("out of free dentries, can not create automount '%s'\n",
name);
- kfree(fsd);
return failed_creating(dentry);
}
make_empty_dir_inode(inode);
inode->i_flags |= S_AUTOMOUNT;
inode->i_private = data;
- dentry->d_fsdata = fsd;
+ DEBUGFS_I(inode)->automount = f;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
d_instantiate(dentry, inode);
@@ -730,7 +726,7 @@ static void __debugfs_file_removed(struct dentry *dentry)
*/
smp_mb();
fsd = READ_ONCE(dentry->d_fsdata);
- if ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT)
+ if (!fsd)
return;
/* if this was the last reference, we're done */
@@ -834,76 +830,70 @@ void debugfs_lookup_and_remove(const char *name, struct dentry *parent)
EXPORT_SYMBOL_GPL(debugfs_lookup_and_remove);
/**
- * debugfs_rename - rename a file/directory in the debugfs filesystem
- * @old_dir: a pointer to the parent dentry for the renamed object. This
- * should be a directory dentry.
- * @old_dentry: dentry of an object to be renamed.
- * @new_dir: a pointer to the parent dentry where the object should be
- * moved. This should be a directory dentry.
- * @new_name: a pointer to a string containing the target name.
+ * debugfs_change_name - rename a file/directory in the debugfs filesystem
+ * @dentry: dentry of an object to be renamed.
+ * @fmt: format for new name
*
* This function renames a file/directory in debugfs. The target must not
* exist for rename to succeed.
*
- * This function will return a pointer to old_dentry (which is updated to
- * reflect renaming) if it succeeds. If an error occurs, ERR_PTR(-ERROR)
- * will be returned.
+ * This function will return 0 on success and -E... on failure.
*
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned.
*/
-struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
- struct dentry *new_dir, const char *new_name)
+int __printf(2, 3) debugfs_change_name(struct dentry *dentry, const char *fmt, ...)
{
- int error;
- struct dentry *dentry = NULL, *trap;
+ int error = 0;
+ const char *new_name;
struct name_snapshot old_name;
+ struct dentry *parent, *target;
+ struct inode *dir;
+ va_list ap;
- if (IS_ERR(old_dir))
- return old_dir;
- if (IS_ERR(new_dir))
- return new_dir;
- if (IS_ERR_OR_NULL(old_dentry))
- return old_dentry;
-
- trap = lock_rename(new_dir, old_dir);
- /* Source or destination directories don't exist? */
- if (d_really_is_negative(old_dir) || d_really_is_negative(new_dir))
- goto exit;
- /* Source does not exist, cyclic rename, or mountpoint? */
- if (d_really_is_negative(old_dentry) || old_dentry == trap ||
- d_mountpoint(old_dentry))
- goto exit;
- dentry = lookup_one_len(new_name, new_dir, strlen(new_name));
- /* Lookup failed, cyclic rename or target exists? */
- if (IS_ERR(dentry) || dentry == trap || d_really_is_positive(dentry))
- goto exit;
-
- take_dentry_name_snapshot(&old_name, old_dentry);
-
- error = simple_rename(&nop_mnt_idmap, d_inode(old_dir), old_dentry,
- d_inode(new_dir), dentry, 0);
- if (error) {
- release_dentry_name_snapshot(&old_name);
- goto exit;
+ if (IS_ERR_OR_NULL(dentry))
+ return 0;
+
+ va_start(ap, fmt);
+ new_name = kvasprintf_const(GFP_KERNEL, fmt, ap);
+ va_end(ap);
+ if (!new_name)
+ return -ENOMEM;
+
+ parent = dget_parent(dentry);
+ dir = d_inode(parent);
+ inode_lock(dir);
+
+ take_dentry_name_snapshot(&old_name, dentry);
+
+ if (WARN_ON_ONCE(dentry->d_parent != parent)) {
+ error = -EINVAL;
+ goto out;
}
- d_move(old_dentry, dentry);
- fsnotify_move(d_inode(old_dir), d_inode(new_dir), &old_name.name,
- d_is_dir(old_dentry),
- NULL, old_dentry);
+ if (strcmp(old_name.name.name, new_name) == 0)
+ goto out;
+ target = lookup_one_len(new_name, parent, strlen(new_name));
+ if (IS_ERR(target)) {
+ error = PTR_ERR(target);
+ goto out;
+ }
+ if (d_really_is_positive(target)) {
+ dput(target);
+ error = -EINVAL;
+ goto out;
+ }
+ simple_rename_timestamp(dir, dentry, dir, target);
+ d_move(dentry, target);
+ dput(target);
+ fsnotify_move(dir, dir, &old_name.name, d_is_dir(dentry), NULL, dentry);
+out:
release_dentry_name_snapshot(&old_name);
- unlock_rename(new_dir, old_dir);
- dput(dentry);
- return old_dentry;
-exit:
- if (dentry && !IS_ERR(dentry))
- dput(dentry);
- unlock_rename(new_dir, old_dir);
- if (IS_ERR(dentry))
- return dentry;
- return ERR_PTR(-EINVAL);
+ inode_unlock(dir);
+ dput(parent);
+ kfree_const(new_name);
+ return error;
}
-EXPORT_SYMBOL_GPL(debugfs_rename);
+EXPORT_SYMBOL_GPL(debugfs_change_name);
/**
* debugfs_initialized - Tells whether debugfs has been registered
@@ -939,12 +929,22 @@ static int __init debugfs_init(void)
if (retval)
return retval;
- retval = register_filesystem(&debug_fs_type);
- if (retval)
+ debugfs_inode_cachep = kmem_cache_create("debugfs_inode_cache",
+ sizeof(struct debugfs_inode_info), 0,
+ SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
+ init_once);
+ if (debugfs_inode_cachep == NULL) {
sysfs_remove_mount_point(kernel_kobj, "debug");
- else
- debugfs_registered = true;
+ return -ENOMEM;
+ }
- return retval;
+ retval = register_filesystem(&debug_fs_type);
+ if (retval) { // Really not going to happen
+ sysfs_remove_mount_point(kernel_kobj, "debug");
+ kmem_cache_destroy(debugfs_inode_cachep);
+ return retval;
+ }
+ debugfs_registered = true;
+ return 0;
}
core_initcall(debugfs_init);