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-rw-r--r--fs/debugfs/file.c299
-rw-r--r--fs/debugfs/inode.c368
2 files changed, 505 insertions, 162 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 89d394d8fe2..63146295153 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -15,9 +15,13 @@
#include <linux/module.h>
#include <linux/fs.h>
+#include <linux/seq_file.h>
#include <linux/pagemap.h>
#include <linux/namei.h>
#include <linux/debugfs.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/atomic.h>
static ssize_t default_read_file(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
@@ -31,18 +35,10 @@ static ssize_t default_write_file(struct file *file, const char __user *buf,
return count;
}
-static int default_open(struct inode *inode, struct file *file)
-{
- if (inode->i_private)
- file->private_data = inode->i_private;
-
- return 0;
-}
-
const struct file_operations debugfs_file_operations = {
.read = default_read_file,
.write = default_write_file,
- .open = default_open,
+ .open = simple_open,
.llseek = noop_llseek,
};
@@ -95,7 +91,7 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_u8(const char *name, mode_t mode,
+struct dentry *debugfs_create_u8(const char *name, umode_t mode,
struct dentry *parent, u8 *value)
{
/* if there are no write bits set, make read only */
@@ -147,7 +143,7 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_u16(const char *name, mode_t mode,
+struct dentry *debugfs_create_u16(const char *name, umode_t mode,
struct dentry *parent, u16 *value)
{
/* if there are no write bits set, make read only */
@@ -199,7 +195,7 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_u32(const char *name, mode_t mode,
+struct dentry *debugfs_create_u32(const char *name, umode_t mode,
struct dentry *parent, u32 *value)
{
/* if there are no write bits set, make read only */
@@ -252,7 +248,7 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_u64(const char *name, mode_t mode,
+struct dentry *debugfs_create_u64(const char *name, umode_t mode,
struct dentry *parent, u64 *value)
{
/* if there are no write bits set, make read only */
@@ -298,7 +294,7 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n
* @value: a pointer to the variable that the file should read to and write
* from.
*/
-struct dentry *debugfs_create_x8(const char *name, mode_t mode,
+struct dentry *debugfs_create_x8(const char *name, umode_t mode,
struct dentry *parent, u8 *value)
{
/* if there are no write bits set, make read only */
@@ -322,7 +318,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_x8);
* @value: a pointer to the variable that the file should read to and write
* from.
*/
-struct dentry *debugfs_create_x16(const char *name, mode_t mode,
+struct dentry *debugfs_create_x16(const char *name, umode_t mode,
struct dentry *parent, u16 *value)
{
/* if there are no write bits set, make read only */
@@ -346,7 +342,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_x16);
* @value: a pointer to the variable that the file should read to and write
* from.
*/
-struct dentry *debugfs_create_x32(const char *name, mode_t mode,
+struct dentry *debugfs_create_x32(const char *name, umode_t mode,
struct dentry *parent, u32 *value)
{
/* if there are no write bits set, make read only */
@@ -370,7 +366,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_x32);
* @value: a pointer to the variable that the file should read to and write
* from.
*/
-struct dentry *debugfs_create_x64(const char *name, mode_t mode,
+struct dentry *debugfs_create_x64(const char *name, umode_t mode,
struct dentry *parent, u64 *value)
{
return debugfs_create_file(name, mode, parent, value, &fops_x64);
@@ -401,13 +397,54 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
* @value: a pointer to the variable that the file should read to and write
* from.
*/
-struct dentry *debugfs_create_size_t(const char *name, mode_t mode,
+struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
struct dentry *parent, size_t *value)
{
return debugfs_create_file(name, mode, parent, value, &fops_size_t);
}
EXPORT_SYMBOL_GPL(debugfs_create_size_t);
+static int debugfs_atomic_t_set(void *data, u64 val)
+{
+ atomic_set((atomic_t *)data, val);
+ return 0;
+}
+static int debugfs_atomic_t_get(void *data, u64 *val)
+{
+ *val = atomic_read((atomic_t *)data);
+ return 0;
+}
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
+ debugfs_atomic_t_set, "%lld\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_ro, debugfs_atomic_t_get, NULL, "%lld\n");
+DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, "%lld\n");
+
+/**
+ * debugfs_create_atomic_t - create a debugfs file that is used to read and
+ * write an atomic_t value
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @value: a pointer to the variable that the file should read to and write
+ * from.
+ */
+struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
+ struct dentry *parent, atomic_t *value)
+{
+ /* if there are no write bits set, make read only */
+ if (!(mode & S_IWUGO))
+ return debugfs_create_file(name, mode, parent, value,
+ &fops_atomic_t_ro);
+ /* if there are no read bits set, make write only */
+ if (!(mode & S_IRUGO))
+ return debugfs_create_file(name, mode, parent, value,
+ &fops_atomic_t_wo);
+
+ return debugfs_create_file(name, mode, parent, value, &fops_atomic_t);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_atomic_t);
static ssize_t read_file_bool(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
@@ -428,33 +465,25 @@ static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
char buf[32];
- int buf_size;
+ size_t buf_size;
+ bool bv;
u32 *val = file->private_data;
buf_size = min(count, (sizeof(buf)-1));
if (copy_from_user(buf, user_buf, buf_size))
return -EFAULT;
- switch (buf[0]) {
- case 'y':
- case 'Y':
- case '1':
- *val = 1;
- break;
- case 'n':
- case 'N':
- case '0':
- *val = 0;
- break;
- }
-
+ buf[buf_size] = '\0';
+ if (strtobool(buf, &bv) == 0)
+ *val = bv;
+
return count;
}
static const struct file_operations fops_bool = {
.read = read_file_bool,
.write = write_file_bool,
- .open = default_open,
+ .open = simple_open,
.llseek = default_llseek,
};
@@ -482,7 +511,7 @@ static const struct file_operations fops_bool = {
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_bool(const char *name, mode_t mode,
+struct dentry *debugfs_create_bool(const char *name, umode_t mode,
struct dentry *parent, u32 *value)
{
return debugfs_create_file(name, mode, parent, value, &fops_bool);
@@ -499,7 +528,7 @@ static ssize_t read_file_blob(struct file *file, char __user *user_buf,
static const struct file_operations fops_blob = {
.read = read_file_blob,
- .open = default_open,
+ .open = simple_open,
.llseek = default_llseek,
};
@@ -527,10 +556,208 @@ static const struct file_operations fops_blob = {
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
* code.
*/
-struct dentry *debugfs_create_blob(const char *name, mode_t mode,
+struct dentry *debugfs_create_blob(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_blob_wrapper *blob)
{
return debugfs_create_file(name, mode, parent, blob, &fops_blob);
}
EXPORT_SYMBOL_GPL(debugfs_create_blob);
+
+struct array_data {
+ void *array;
+ u32 elements;
+};
+
+static size_t u32_format_array(char *buf, size_t bufsize,
+ u32 *array, int array_size)
+{
+ size_t ret = 0;
+
+ while (--array_size >= 0) {
+ size_t len;
+ char term = array_size ? ' ' : '\n';
+
+ len = snprintf(buf, bufsize, "%u%c", *array++, term);
+ ret += len;
+
+ buf += len;
+ bufsize -= len;
+ }
+ return ret;
+}
+
+static int u32_array_open(struct inode *inode, struct file *file)
+{
+ struct array_data *data = inode->i_private;
+ int size, elements = data->elements;
+ char *buf;
+
+ /*
+ * Max size:
+ * - 10 digits + ' '/'\n' = 11 bytes per number
+ * - terminating NUL character
+ */
+ size = elements*11;
+ buf = kmalloc(size+1, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ buf[size] = 0;
+
+ file->private_data = buf;
+ u32_format_array(buf, size, data->array, data->elements);
+
+ return nonseekable_open(inode, file);
+}
+
+static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
+ loff_t *ppos)
+{
+ size_t size = strlen(file->private_data);
+
+ return simple_read_from_buffer(buf, len, ppos,
+ file->private_data, size);
+}
+
+static int u32_array_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+
+ return 0;
+}
+
+static const struct file_operations u32_array_fops = {
+ .owner = THIS_MODULE,
+ .open = u32_array_open,
+ .release = u32_array_release,
+ .read = u32_array_read,
+ .llseek = no_llseek,
+};
+
+/**
+ * debugfs_create_u32_array - create a debugfs file that is used to read u32
+ * array.
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have.
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @array: u32 array that provides data.
+ * @elements: total number of elements in the array.
+ *
+ * This function creates a file in debugfs with the given name that exports
+ * @array as data. If the @mode variable is so set it can be read from.
+ * Writing is not supported. Seek within the file is also not supported.
+ * Once array is created its size can not be changed.
+ *
+ * The function returns a pointer to dentry on success. If debugfs is not
+ * enabled in the kernel, the value -%ENODEV will be returned.
+ */
+struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *array, u32 elements)
+{
+ struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
+
+ if (data == NULL)
+ return NULL;
+
+ data->array = array;
+ data->elements = elements;
+
+ return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
+
+#ifdef CONFIG_HAS_IOMEM
+
+/*
+ * The regset32 stuff is used to print 32-bit registers using the
+ * seq_file utilities. We offer printing a register set in an already-opened
+ * sequential file or create a debugfs file that only prints a regset32.
+ */
+
+/**
+ * debugfs_print_regs32 - use seq_print to describe a set of registers
+ * @s: the seq_file structure being used to generate output
+ * @regs: an array if struct debugfs_reg32 structures
+ * @nregs: the length of the above array
+ * @base: the base address to be used in reading the registers
+ * @prefix: a string to be prefixed to every output line
+ *
+ * This function outputs a text block describing the current values of
+ * some 32-bit hardware registers. It is meant to be used within debugfs
+ * files based on seq_file that need to show registers, intermixed with other
+ * information. The prefix argument may be used to specify a leading string,
+ * because some peripherals have several blocks of identical registers,
+ * for example configuration of dma channels
+ */
+int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+ int nregs, void __iomem *base, char *prefix)
+{
+ int i, ret = 0;
+
+ for (i = 0; i < nregs; i++, regs++) {
+ if (prefix)
+ ret += seq_printf(s, "%s", prefix);
+ ret += seq_printf(s, "%s = 0x%08x\n", regs->name,
+ readl(base + regs->offset));
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(debugfs_print_regs32);
+
+static int debugfs_show_regset32(struct seq_file *s, void *data)
+{
+ struct debugfs_regset32 *regset = s->private;
+
+ debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "");
+ return 0;
+}
+
+static int debugfs_open_regset32(struct inode *inode, struct file *file)
+{
+ return single_open(file, debugfs_show_regset32, inode->i_private);
+}
+
+static const struct file_operations fops_regset32 = {
+ .open = debugfs_open_regset32,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+/**
+ * debugfs_create_regset32 - create a debugfs file that returns register values
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
+ * to an array of register definitions, the array size and the base
+ * address where the register bank is to be found.
+ *
+ * This function creates a file in debugfs with the given name that reports
+ * the names and values of a set of 32-bit registers. If the @mode variable
+ * is so set it can be read from. Writing is not supported.
+ *
+ * This function will return a pointer to a dentry if it succeeds. This
+ * pointer must be passed to the debugfs_remove() function when the file is
+ * to be removed (no automatic cleanup happens if your module is unloaded,
+ * you are responsible here.) If an error occurs, %NULL will be returned.
+ *
+ * If debugfs is not enabled in the kernel, the value -%ENODEV will be
+ * returned. It is not wise to check for this value, but rather, check for
+ * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
+ * code.
+ */
+struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
+ struct dentry *parent,
+ struct debugfs_regset32 *regset)
+{
+ return debugfs_create_file(name, mode, parent, regset, &fops_regset32);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_regset32);
+
+#endif /* CONFIG_HAS_IOMEM */
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 37a8ca7c122..8c41b52da35 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -1,5 +1,5 @@
/*
- * file.c - part of debugfs, a tiny little debug file system
+ * inode.c - part of debugfs, a tiny little debug file system
*
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2004 IBM Inc.
@@ -13,9 +13,6 @@
*
*/
-/* uncomment to get debug messages from the debug filesystem, ah the irony. */
-/* #define DEBUG */
-
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/mount.h>
@@ -26,14 +23,18 @@
#include <linux/debugfs.h>
#include <linux/fsnotify.h>
#include <linux/string.h>
+#include <linux/seq_file.h>
+#include <linux/parser.h>
#include <linux/magic.h>
#include <linux/slab.h>
+#define DEBUGFS_DEFAULT_MODE 0700
+
static struct vfsmount *debugfs_mount;
static int debugfs_mount_count;
static bool debugfs_registered;
-static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t dev,
+static struct inode *debugfs_get_inode(struct super_block *sb, umode_t mode, dev_t dev,
void *data, const struct file_operations *fops)
{
@@ -53,13 +54,11 @@ static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t d
break;
case S_IFLNK:
inode->i_op = &debugfs_link_operations;
- inode->i_fop = fops;
inode->i_private = data;
break;
case S_IFDIR:
inode->i_op = &simple_dir_inode_operations;
- inode->i_fop = fops ? fops : &simple_dir_operations;
- inode->i_private = data;
+ inode->i_fop = &simple_dir_operations;
/* directory inodes start off with i_nlink == 2
* (for "." entry) */
@@ -72,7 +71,7 @@ static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t d
/* SMP-safe */
static int debugfs_mknod(struct inode *dir, struct dentry *dentry,
- int mode, dev_t dev, void *data,
+ umode_t mode, dev_t dev, void *data,
const struct file_operations *fops)
{
struct inode *inode;
@@ -90,13 +89,12 @@ static int debugfs_mknod(struct inode *dir, struct dentry *dentry,
return error;
}
-static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, int mode,
- void *data, const struct file_operations *fops)
+static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
int res;
mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR;
- res = debugfs_mknod(dir, dentry, mode, 0, data, fops);
+ res = debugfs_mknod(dir, dentry, mode, 0, NULL, NULL);
if (!res) {
inc_nlink(dir);
fsnotify_mkdir(dir, dentry);
@@ -104,14 +102,14 @@ static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, int mode,
return res;
}
-static int debugfs_link(struct inode *dir, struct dentry *dentry, int mode,
- void *data, const struct file_operations *fops)
+static int debugfs_link(struct inode *dir, struct dentry *dentry, umode_t mode,
+ void *data)
{
mode = (mode & S_IALLUGO) | S_IFLNK;
- return debugfs_mknod(dir, dentry, mode, 0, data, fops);
+ return debugfs_mknod(dir, dentry, mode, 0, data, NULL);
}
-static int debugfs_create(struct inode *dir, struct dentry *dentry, int mode,
+static int debugfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
void *data, const struct file_operations *fops)
{
int res;
@@ -128,11 +126,165 @@ static inline int debugfs_positive(struct dentry *dentry)
return dentry->d_inode && !d_unhashed(dentry);
}
+struct debugfs_mount_opts {
+ kuid_t uid;
+ kgid_t gid;
+ umode_t mode;
+};
+
+enum {
+ Opt_uid,
+ Opt_gid,
+ Opt_mode,
+ Opt_err
+};
+
+static const match_table_t tokens = {
+ {Opt_uid, "uid=%u"},
+ {Opt_gid, "gid=%u"},
+ {Opt_mode, "mode=%o"},
+ {Opt_err, NULL}
+};
+
+struct debugfs_fs_info {
+ struct debugfs_mount_opts mount_opts;
+};
+
+static int debugfs_parse_options(char *data, struct debugfs_mount_opts *opts)
+{
+ substring_t args[MAX_OPT_ARGS];
+ int option;
+ int token;
+ kuid_t uid;
+ kgid_t gid;
+ char *p;
+
+ opts->mode = DEBUGFS_DEFAULT_MODE;
+
+ while ((p = strsep(&data, ",")) != NULL) {
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_uid:
+ if (match_int(&args[0], &option))
+ return -EINVAL;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid))
+ return -EINVAL;
+ opts->uid = uid;
+ break;
+ case Opt_gid:
+ if (match_int(&args[0], &option))
+ return -EINVAL;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid))
+ return -EINVAL;
+ opts->gid = gid;
+ break;
+ case Opt_mode:
+ if (match_octal(&args[0], &option))
+ return -EINVAL;
+ opts->mode = option & S_IALLUGO;
+ break;
+ /*
+ * We might like to report bad mount options here;
+ * but traditionally debugfs has ignored all mount options
+ */
+ }
+ }
+
+ return 0;
+}
+
+static int debugfs_apply_options(struct super_block *sb)
+{
+ struct debugfs_fs_info *fsi = sb->s_fs_info;
+ struct inode *inode = sb->s_root->d_inode;
+ struct debugfs_mount_opts *opts = &fsi->mount_opts;
+
+ inode->i_mode &= ~S_IALLUGO;
+ inode->i_mode |= opts->mode;
+
+ inode->i_uid = opts->uid;
+ inode->i_gid = opts->gid;
+
+ return 0;
+}
+
+static int debugfs_remount(struct super_block *sb, int *flags, char *data)
+{
+ int err;
+ struct debugfs_fs_info *fsi = sb->s_fs_info;
+
+ sync_filesystem(sb);
+ err = debugfs_parse_options(data, &fsi->mount_opts);
+ if (err)
+ goto fail;
+
+ debugfs_apply_options(sb);
+
+fail:
+ return err;
+}
+
+static int debugfs_show_options(struct seq_file *m, struct dentry *root)
+{
+ struct debugfs_fs_info *fsi = root->d_sb->s_fs_info;
+ struct debugfs_mount_opts *opts = &fsi->mount_opts;
+
+ if (!uid_eq(opts->uid, GLOBAL_ROOT_UID))
+ seq_printf(m, ",uid=%u",
+ from_kuid_munged(&init_user_ns, opts->uid));
+ if (!gid_eq(opts->gid, GLOBAL_ROOT_GID))
+ seq_printf(m, ",gid=%u",
+ from_kgid_munged(&init_user_ns, opts->gid));
+ if (opts->mode != DEBUGFS_DEFAULT_MODE)
+ seq_printf(m, ",mode=%o", opts->mode);
+
+ return 0;
+}
+
+static const struct super_operations debugfs_super_operations = {
+ .statfs = simple_statfs,
+ .remount_fs = debugfs_remount,
+ .show_options = debugfs_show_options,
+};
+
static int debug_fill_super(struct super_block *sb, void *data, int silent)
{
static struct tree_descr debug_files[] = {{""}};
+ struct debugfs_fs_info *fsi;
+ int err;
- return simple_fill_super(sb, DEBUGFS_MAGIC, debug_files);
+ save_mount_options(sb, data);
+
+ fsi = kzalloc(sizeof(struct debugfs_fs_info), GFP_KERNEL);
+ sb->s_fs_info = fsi;
+ if (!fsi) {
+ err = -ENOMEM;
+ goto fail;
+ }
+
+ err = debugfs_parse_options(data, &fsi->mount_opts);
+ if (err)
+ goto fail;
+
+ err = simple_fill_super(sb, DEBUGFS_MAGIC, debug_files);
+ if (err)
+ goto fail;
+
+ sb->s_op = &debugfs_super_operations;
+
+ debugfs_apply_options(sb);
+
+ return 0;
+
+fail:
+ kfree(fsi);
+ sb->s_fs_info = NULL;
+ return err;
}
static struct dentry *debug_mount(struct file_system_type *fs_type,
@@ -148,14 +300,21 @@ static struct file_system_type debug_fs_type = {
.mount = debug_mount,
.kill_sb = kill_litter_super,
};
+MODULE_ALIAS_FS("debugfs");
-static int debugfs_create_by_name(const char *name, mode_t mode,
- struct dentry *parent,
- struct dentry **dentry,
- void *data,
- const struct file_operations *fops)
+static struct dentry *__create_file(const char *name, umode_t mode,
+ struct dentry *parent, void *data,
+ const struct file_operations *fops)
{
- int error = 0;
+ struct dentry *dentry = NULL;
+ int error;
+
+ pr_debug("debugfs: creating file '%s'\n",name);
+
+ error = simple_pin_fs(&debug_fs_type, &debugfs_mount,
+ &debugfs_mount_count);
+ if (error)
+ goto exit;
/* If the parent is not specified, we create it in the root.
* We need the root dentry to do this, which is in the super
@@ -163,32 +322,36 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
* have around.
*/
if (!parent)
- parent = debugfs_mount->mnt_sb->s_root;
+ parent = debugfs_mount->mnt_root;
- *dentry = NULL;
mutex_lock(&parent->d_inode->i_mutex);
- *dentry = lookup_one_len(name, parent, strlen(name));
- if (!IS_ERR(*dentry)) {
+ dentry = lookup_one_len(name, parent, strlen(name));
+ if (!IS_ERR(dentry)) {
switch (mode & S_IFMT) {
case S_IFDIR:
- error = debugfs_mkdir(parent->d_inode, *dentry, mode,
- data, fops);
+ error = debugfs_mkdir(parent->d_inode, dentry, mode);
+
break;
case S_IFLNK:
- error = debugfs_link(parent->d_inode, *dentry, mode,
- data, fops);
+ error = debugfs_link(parent->d_inode, dentry, mode,
+ data);
break;
default:
- error = debugfs_create(parent->d_inode, *dentry, mode,
+ error = debugfs_create(parent->d_inode, dentry, mode,
data, fops);
break;
}
- dput(*dentry);
+ dput(dentry);
} else
- error = PTR_ERR(*dentry);
+ error = PTR_ERR(dentry);
mutex_unlock(&parent->d_inode->i_mutex);
- return error;
+ if (error) {
+ dentry = NULL;
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ }
+exit:
+ return dentry;
}
/**
@@ -196,7 +359,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have.
* @parent: a pointer to the parent dentry for this file. This should be a
- * directory dentry if set. If this paramater is NULL, then the
+ * directory dentry if set. If this parameter is NULL, then the
* file will be created in the root of the debugfs filesystem.
* @data: a pointer to something that the caller will want to get to later
* on. The inode.i_private pointer will point to this value on
@@ -217,29 +380,19 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
* returned.
*/
-struct dentry *debugfs_create_file(const char *name, mode_t mode,
+struct dentry *debugfs_create_file(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops)
{
- struct dentry *dentry = NULL;
- int error;
-
- pr_debug("debugfs: creating file '%s'\n",name);
-
- error = simple_pin_fs(&debug_fs_type, &debugfs_mount,
- &debugfs_mount_count);
- if (error)
- goto exit;
-
- error = debugfs_create_by_name(name, mode, parent, &dentry,
- data, fops);
- if (error) {
- dentry = NULL;
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
- goto exit;
+ switch (mode & S_IFMT) {
+ case S_IFREG:
+ case 0:
+ break;
+ default:
+ BUG();
}
-exit:
- return dentry;
+
+ return __create_file(name, mode, parent, data, fops);
}
EXPORT_SYMBOL_GPL(debugfs_create_file);
@@ -248,7 +401,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_file);
* @name: a pointer to a string containing the name of the directory to
* create.
* @parent: a pointer to the parent dentry for this file. This should be a
- * directory dentry if set. If this paramater is NULL, then the
+ * directory dentry if set. If this parameter is NULL, then the
* directory will be created in the root of the debugfs filesystem.
*
* This function creates a directory in debugfs with the given name.
@@ -263,8 +416,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_file);
*/
struct dentry *debugfs_create_dir(const char *name, struct dentry *parent)
{
- return debugfs_create_file(name,
- S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
+ return __create_file(name, S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
parent, NULL, NULL);
}
EXPORT_SYMBOL_GPL(debugfs_create_dir);
@@ -274,7 +426,7 @@ EXPORT_SYMBOL_GPL(debugfs_create_dir);
* @name: a pointer to a string containing the name of the symbolic link to
* create.
* @parent: a pointer to the parent dentry for this symbolic link. This
- * should be a directory dentry if set. If this paramater is NULL,
+ * should be a directory dentry if set. If this parameter is NULL,
* then the symbolic link will be created in the root of the debugfs
* filesystem.
* @target: a pointer to a string containing the path to the target of the
@@ -302,15 +454,14 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
if (!link)
return NULL;
- result = debugfs_create_file(name, S_IFLNK | S_IRWXUGO, parent, link,
- NULL);
+ result = __create_file(name, S_IFLNK | S_IRWXUGO, parent, link, NULL);
if (!result)
kfree(link);
return result;
}
EXPORT_SYMBOL_GPL(debugfs_create_symlink);
-static void __debugfs_remove(struct dentry *dentry, struct dentry *parent)
+static int __debugfs_remove(struct dentry *dentry, struct dentry *parent)
{
int ret = 0;
@@ -333,6 +484,7 @@ static void __debugfs_remove(struct dentry *dentry, struct dentry *parent)
dput(dentry);
}
}
+ return ret;
}
/**
@@ -351,8 +503,9 @@ static void __debugfs_remove(struct dentry *dentry, struct dentry *parent)
void debugfs_remove(struct dentry *dentry)
{
struct dentry *parent;
-
- if (!dentry)
+ int ret;
+
+ if (IS_ERR_OR_NULL(dentry))
return;
parent = dentry->d_parent;
@@ -360,9 +513,10 @@ void debugfs_remove(struct dentry *dentry)
return;
mutex_lock(&parent->d_inode->i_mutex);
- __debugfs_remove(dentry, parent);
+ ret = __debugfs_remove(dentry, parent);
mutex_unlock(&parent->d_inode->i_mutex);
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ if (!ret)
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
EXPORT_SYMBOL_GPL(debugfs_remove);
@@ -380,10 +534,9 @@ EXPORT_SYMBOL_GPL(debugfs_remove);
*/
void debugfs_remove_recursive(struct dentry *dentry)
{
- struct dentry *child;
- struct dentry *parent;
+ struct dentry *child, *next, *parent;
- if (!dentry)
+ if (IS_ERR_OR_NULL(dentry))
return;
parent = dentry->d_parent;
@@ -391,61 +544,36 @@ void debugfs_remove_recursive(struct dentry *dentry)
return;
parent = dentry;
+ down:
mutex_lock(&parent->d_inode->i_mutex);
+ list_for_each_entry_safe(child, next, &parent->d_subdirs, d_u.d_child) {
+ if (!debugfs_positive(child))
+ continue;
- while (1) {
- /*
- * When all dentries under "parent" has been removed,
- * walk up the tree until we reach our starting point.
- */
- if (list_empty(&parent->d_subdirs)) {
- mutex_unlock(&parent->d_inode->i_mutex);
- if (parent == dentry)
- break;
- parent = parent->d_parent;
- mutex_lock(&parent->d_inode->i_mutex);
- }
- child = list_entry(parent->d_subdirs.next, struct dentry,
- d_u.d_child);
- next_sibling:
-
- /*
- * If "child" isn't empty, walk down the tree and
- * remove all its descendants first.
- */
+ /* perhaps simple_empty(child) makes more sense */
if (!list_empty(&child->d_subdirs)) {
mutex_unlock(&parent->d_inode->i_mutex);
parent = child;
- mutex_lock(&parent->d_inode->i_mutex);
- continue;
+ goto down;
}
- __debugfs_remove(child, parent);
- if (parent->d_subdirs.next == &child->d_u.d_child) {
- /*
- * Try the next sibling.
- */
- if (child->d_u.d_child.next != &parent->d_subdirs) {
- child = list_entry(child->d_u.d_child.next,
- struct dentry,
- d_u.d_child);
- goto next_sibling;
- }
-
- /*
- * Avoid infinite loop if we fail to remove
- * one dentry.
- */
- mutex_unlock(&parent->d_inode->i_mutex);
- break;
- }
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ up:
+ if (!__debugfs_remove(child, parent))
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
- parent = dentry->d_parent;
+ mutex_unlock(&parent->d_inode->i_mutex);
+ child = parent;
+ parent = parent->d_parent;
mutex_lock(&parent->d_inode->i_mutex);
- __debugfs_remove(dentry, parent);
+
+ if (child != dentry) {
+ next = list_next_entry(child, d_u.d_child);
+ goto up;
+ }
+
+ if (!__debugfs_remove(child, parent))
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
mutex_unlock(&parent->d_inode->i_mutex);
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
}
EXPORT_SYMBOL_GPL(debugfs_remove_recursive);
@@ -540,17 +668,5 @@ static int __init debugfs_init(void)
return retval;
}
-
-static void __exit debugfs_exit(void)
-{
- debugfs_registered = false;
-
- simple_release_fs(&debugfs_mount, &debugfs_mount_count);
- unregister_filesystem(&debug_fs_type);
- kobject_put(debug_kobj);
-}
-
core_initcall(debugfs_init);
-module_exit(debugfs_exit);
-MODULE_LICENSE("GPL");