diff options
Diffstat (limited to 'fs/debugfs')
| -rw-r--r-- | fs/debugfs/file.c | 418 | ||||
| -rw-r--r-- | fs/debugfs/inode.c | 445 |
2 files changed, 714 insertions, 149 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index fddffe4851f..63146295153 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -9,15 +9,19 @@ * 2 as published by the Free Software Foundation. * * debugfs is for people to use instead of /proc or /sys. - * See Documentation/DocBook/kernel-api for more details. + * See Documentation/DocBook/filesystems for more details. * */ #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 +35,11 @@ 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, }; static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd) @@ -67,6 +64,8 @@ static int debugfs_u8_get(void *data, u64 *val) return 0; } DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n"); /** * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value @@ -92,9 +91,16 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u8_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u8_wo); + return debugfs_create_file(name, mode, parent, value, &fops_u8); } EXPORT_SYMBOL_GPL(debugfs_create_u8); @@ -110,6 +116,8 @@ static int debugfs_u16_get(void *data, u64 *val) return 0; } DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n"); /** * debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value @@ -135,9 +143,16 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u16_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u16_wo); + return debugfs_create_file(name, mode, parent, value, &fops_u16); } EXPORT_SYMBOL_GPL(debugfs_create_u16); @@ -153,6 +168,8 @@ static int debugfs_u32_get(void *data, u64 *val) return 0; } DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n"); /** * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value @@ -178,9 +195,16 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u32_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u32_wo); + return debugfs_create_file(name, mode, parent, value, &fops_u32); } EXPORT_SYMBOL_GPL(debugfs_create_u32); @@ -197,6 +221,8 @@ static int debugfs_u64_get(void *data, u64 *val) return 0; } DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n"); /** * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value @@ -222,21 +248,36 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u64_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_u64_wo); + return debugfs_create_file(name, mode, parent, value, &fops_u64); } EXPORT_SYMBOL_GPL(debugfs_create_u64); DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n"); DEFINE_SIMPLE_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, "0x%04llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n"); DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n"); +DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n"); + +DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n"); /* - * debugfs_create_x{8,16,32} - create a debugfs file that is used to read and write an unsigned {8,16,32}-bit value + * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value * * These functions are exactly the same as the above functions (but use a hex * output for the decimal challenged). For details look at the above unsigned @@ -253,9 +294,16 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x8_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x8_wo); + return debugfs_create_file(name, mode, parent, value, &fops_x8); } EXPORT_SYMBOL_GPL(debugfs_create_x8); @@ -270,9 +318,16 @@ 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x16_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x16_wo); + return debugfs_create_file(name, mode, parent, value, &fops_x16); } EXPORT_SYMBOL_GPL(debugfs_create_x16); @@ -287,13 +342,110 @@ 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 */ + if (!(mode & S_IWUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x32_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file(name, mode, parent, value, &fops_x32_wo); + return debugfs_create_file(name, mode, parent, value, &fops_x32); } EXPORT_SYMBOL_GPL(debugfs_create_x32); +/** + * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit 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_x64(const char *name, umode_t mode, + struct dentry *parent, u64 *value) +{ + return debugfs_create_file(name, mode, parent, value, &fops_x64); +} +EXPORT_SYMBOL_GPL(debugfs_create_x64); + + +static int debugfs_size_t_set(void *data, u64 val) +{ + *(size_t *)data = val; + return 0; +} +static int debugfs_size_t_get(void *data, u64 *val) +{ + *val = *(size_t *)data; + return 0; +} +DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set, + "%llu\n"); /* %llu and %zu are more or less the same */ + +/** + * debugfs_create_size_t - create a debugfs file that is used to read and write an size_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_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) { @@ -313,33 +465,26 @@ 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, }; /** @@ -366,7 +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); @@ -383,11 +528,12 @@ 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, }; /** - * debugfs_create_blob - create a debugfs file that is used to read and write a binary blob + * debugfs_create_blob - create a debugfs file that is used to read a binary blob * @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 @@ -410,10 +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 e9602d85c11..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> @@ -26,31 +23,38 @@ #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_MAGIC 0x64626720 +#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, umode_t mode, dev_t dev, + void *data, const struct file_operations *fops) -static struct inode *debugfs_get_inode(struct super_block *sb, int mode, dev_t dev) { struct inode *inode = new_inode(sb); if (inode) { + inode->i_ino = get_next_ino(); inode->i_mode = mode; - inode->i_uid = 0; - inode->i_gid = 0; - inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; switch (mode & S_IFMT) { default: init_special_inode(inode, mode, dev); break; case S_IFREG: - inode->i_fop = &debugfs_file_operations; + inode->i_fop = fops ? fops : &debugfs_file_operations; + inode->i_private = data; break; case S_IFLNK: inode->i_op = &debugfs_link_operations; + inode->i_private = data; break; case S_IFDIR: inode->i_op = &simple_dir_inode_operations; @@ -67,7 +71,8 @@ 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) + umode_t mode, dev_t dev, void *data, + const struct file_operations *fops) { struct inode *inode; int error = -EPERM; @@ -75,7 +80,7 @@ static int debugfs_mknod(struct inode *dir, struct dentry *dentry, if (dentry->d_inode) return -EEXIST; - inode = debugfs_get_inode(dir->i_sb, mode, dev); + inode = debugfs_get_inode(dir->i_sb, mode, dev, data, fops); if (inode) { d_instantiate(dentry, inode); dget(dentry); @@ -84,12 +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) +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); + res = debugfs_mknod(dir, dentry, mode, 0, NULL, NULL); if (!res) { inc_nlink(dir); fsnotify_mkdir(dir, dentry); @@ -97,18 +102,20 @@ 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) +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); + 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; mode = (mode & S_IALLUGO) | S_IFREG; - res = debugfs_mknod(dir, dentry, mode, 0); + res = debugfs_mknod(dir, dentry, mode, 0, data, fops); if (!res) fsnotify_create(dir, dentry); return res; @@ -119,77 +126,240 @@ 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; + + 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; - return simple_fill_super(sb, DEBUGFS_MAGIC, debug_files); + sb->s_op = &debugfs_super_operations; + + debugfs_apply_options(sb); + + return 0; + +fail: + kfree(fsi); + sb->s_fs_info = NULL; + return err; } -static int debug_get_sb(struct file_system_type *fs_type, +static struct dentry *debug_mount(struct file_system_type *fs_type, int flags, const char *dev_name, - void *data, struct vfsmount *mnt) + void *data) { - return get_sb_single(fs_type, flags, data, debug_fill_super, mnt); + return mount_single(fs_type, flags, data, debug_fill_super); } static struct file_system_type debug_fs_type = { .owner = THIS_MODULE, .name = "debugfs", - .get_sb = debug_get_sb, + .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) +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 * block. A pointer to that is in the struct vfsmount that we * have around. */ - if (!parent) { - if (debugfs_mount && debugfs_mount->mnt_sb) { - parent = debugfs_mount->mnt_sb->s_root; - } - } - if (!parent) { - pr_debug("debugfs: Ah! can not find a parent!\n"); - return -EFAULT; - } + if (!parent) + 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); + error = debugfs_mkdir(parent->d_inode, dentry, mode); + break; case S_IFLNK: - error = debugfs_link(parent->d_inode, *dentry, mode); + 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; } /** * debugfs_create_file - create a file in the debugfs filesystem * @name: a pointer to a string containing the name of the file to create. - * @mode: the permission that the file should have + * @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 @@ -198,8 +368,8 @@ static int debugfs_create_by_name(const char *name, mode_t mode, * this file. * * This is the basic "create a file" function for debugfs. It allows for a - * wide range of flexibility in createing a file, or a directory (if you - * want to create a directory, the debugfs_create_dir() function is + * wide range of flexibility in creating a file, or a directory (if you want + * to create a directory, the debugfs_create_dir() function is * recommended to be used instead.) * * This function will return a pointer to a dentry if it succeeds. This @@ -210,35 +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); - 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(); } - if (dentry->d_inode) { - if (data) - dentry->d_inode->i_private = data; - if (fops) - dentry->d_inode->i_fop = fops; - } -exit: - return dentry; + return __create_file(name, mode, parent, data, fops); } EXPORT_SYMBOL_GPL(debugfs_create_file); @@ -247,7 +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. @@ -262,8 +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); @@ -273,7 +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 @@ -301,14 +454,39 @@ 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 int __debugfs_remove(struct dentry *dentry, struct dentry *parent) +{ + int ret = 0; + + if (debugfs_positive(dentry)) { + if (dentry->d_inode) { + dget(dentry); + switch (dentry->d_inode->i_mode & S_IFMT) { + case S_IFDIR: + ret = simple_rmdir(parent->d_inode, dentry); + break; + case S_IFLNK: + kfree(dentry->d_inode->i_private); + /* fall through */ + default: + simple_unlink(parent->d_inode, dentry); + break; + } + if (!ret) + d_delete(dentry); + dput(dentry); + } + } + return ret; +} + /** * debugfs_remove - removes a file or directory from the debugfs filesystem * @dentry: a pointer to a the dentry of the file or directory to be @@ -325,9 +503,9 @@ EXPORT_SYMBOL_GPL(debugfs_create_symlink); void debugfs_remove(struct dentry *dentry) { struct dentry *parent; - int ret = 0; - - if (!dentry) + int ret; + + if (IS_ERR_OR_NULL(dentry)) return; parent = dentry->d_parent; @@ -335,29 +513,69 @@ void debugfs_remove(struct dentry *dentry) return; mutex_lock(&parent->d_inode->i_mutex); - if (debugfs_positive(dentry)) { - if (dentry->d_inode) { - dget(dentry); - switch (dentry->d_inode->i_mode & S_IFMT) { - case S_IFDIR: - ret = simple_rmdir(parent->d_inode, dentry); - break; - case S_IFLNK: - kfree(dentry->d_inode->i_private); - /* fall through */ - default: - simple_unlink(parent->d_inode, dentry); - break; - } - if (!ret) - d_delete(dentry); - dput(dentry); + ret = __debugfs_remove(dentry, parent); + mutex_unlock(&parent->d_inode->i_mutex); + if (!ret) + simple_release_fs(&debugfs_mount, &debugfs_mount_count); +} +EXPORT_SYMBOL_GPL(debugfs_remove); + +/** + * debugfs_remove_recursive - recursively removes a directory + * @dentry: a pointer to a the dentry of the directory to be removed. + * + * This function recursively removes a directory tree in debugfs that + * was previously created with a call to another debugfs function + * (like debugfs_create_file() or variants thereof.) + * + * This function is required to be called in order for the file to be + * removed, no automatic cleanup of files will happen when a module is + * removed, you are responsible here. + */ +void debugfs_remove_recursive(struct dentry *dentry) +{ + struct dentry *child, *next, *parent; + + if (IS_ERR_OR_NULL(dentry)) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + 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; + + /* perhaps simple_empty(child) makes more sense */ + if (!list_empty(&child->d_subdirs)) { + mutex_unlock(&parent->d_inode->i_mutex); + parent = child; + goto down; } + up: + if (!__debugfs_remove(child, parent)) + simple_release_fs(&debugfs_mount, &debugfs_mount_count); + } + + mutex_unlock(&parent->d_inode->i_mutex); + child = parent; + parent = parent->d_parent; + mutex_lock(&parent->d_inode->i_mutex); + + 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); +EXPORT_SYMBOL_GPL(debugfs_remove_recursive); /** * debugfs_rename - rename a file/directory in the debugfs filesystem @@ -408,7 +626,7 @@ struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, } d_move(old_dentry, dentry); fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, - old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode), + S_ISDIR(old_dentry->d_inode->i_mode), NULL, old_dentry); fsnotify_oldname_free(old_name); unlock_rename(new_dir, old_dir); @@ -422,6 +640,16 @@ exit: } EXPORT_SYMBOL_GPL(debugfs_rename); +/** + * debugfs_initialized - Tells whether debugfs has been registered + */ +bool debugfs_initialized(void) +{ + return debugfs_registered; +} +EXPORT_SYMBOL_GPL(debugfs_initialized); + + static struct kobject *debug_kobj; static int __init debugfs_init(void) @@ -435,17 +663,10 @@ static int __init debugfs_init(void) retval = register_filesystem(&debug_fs_type); if (retval) kobject_put(debug_kobj); - return retval; -} + else + debugfs_registered = true; -static void __exit debugfs_exit(void) -{ - simple_release_fs(&debugfs_mount, &debugfs_mount_count); - unregister_filesystem(&debug_fs_type); - kobject_put(debug_kobj); + return retval; } - core_initcall(debugfs_init); -module_exit(debugfs_exit); -MODULE_LICENSE("GPL"); |