diff options
Diffstat (limited to 'fs/debugfs')
| -rw-r--r-- | fs/debugfs/Makefile | 4 | ||||
| -rw-r--r-- | fs/debugfs/file.c | 614 | ||||
| -rw-r--r-- | fs/debugfs/inode.c | 691 |
3 files changed, 1309 insertions, 0 deletions
diff --git a/fs/debugfs/Makefile b/fs/debugfs/Makefile new file mode 100644 index 00000000..840c4569 --- /dev/null +++ b/fs/debugfs/Makefile @@ -0,0 +1,4 @@ +debugfs-objs := inode.o file.o + +obj-$(CONFIG_DEBUG_FS) += debugfs.o + diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c new file mode 100644 index 00000000..5dfafdd1 --- /dev/null +++ b/fs/debugfs/file.c @@ -0,0 +1,614 @@ +/* + * file.c - part of debugfs, a tiny little debug file system + * + * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com> + * Copyright (C) 2004 IBM Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * debugfs is for people to use instead of /proc or /sys. + * 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> + +static ssize_t default_read_file(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + return 0; +} + +static ssize_t default_write_file(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + return count; +} + +const struct file_operations debugfs_file_operations = { + .read = default_read_file, + .write = default_write_file, + .open = simple_open, + .llseek = noop_llseek, +}; + +static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + nd_set_link(nd, dentry->d_inode->i_private); + return NULL; +} + +const struct inode_operations debugfs_link_operations = { + .readlink = generic_readlink, + .follow_link = debugfs_follow_link, +}; + +static int debugfs_u8_set(void *data, u64 val) +{ + *(u8 *)data = val; + return 0; +} +static int debugfs_u8_get(void *data, u64 *val) +{ + *val = *(u8 *)data; + 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 + * @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. + * + * This function creates a file in debugfs with the given name that + * contains the value of the variable @value. If the @mode variable is so + * set, it can be read from, and written to. + * + * 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_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); + +static int debugfs_u16_set(void *data, u64 val) +{ + *(u16 *)data = val; + return 0; +} +static int debugfs_u16_get(void *data, u64 *val) +{ + *val = *(u16 *)data; + 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 + * @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. + * + * This function creates a file in debugfs with the given name that + * contains the value of the variable @value. If the @mode variable is so + * set, it can be read from, and written to. + * + * 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_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); + +static int debugfs_u32_set(void *data, u64 val) +{ + *(u32 *)data = val; + return 0; +} +static int debugfs_u32_get(void *data, u64 *val) +{ + *val = *(u32 *)data; + 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 + * @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. + * + * This function creates a file in debugfs with the given name that + * contains the value of the variable @value. If the @mode variable is so + * set, it can be read from, and written to. + * + * 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_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); + +static int debugfs_u64_set(void *data, u64 val) +{ + *(u64 *)data = val; + return 0; +} + +static int debugfs_u64_get(void *data, u64 *val) +{ + *val = *(u64 *)data; + 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 + * @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. + * + * This function creates a file in debugfs with the given name that + * contains the value of the variable @value. If the @mode variable is so + * set, it can be read from, and written to. + * + * 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_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{8,16,32,64} - 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 + * decimal functions. + */ + +/** + * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-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_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); + +/** + * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-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_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); + +/** + * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-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_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 ssize_t read_file_bool(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + char buf[3]; + u32 *val = file->private_data; + + if (*val) + buf[0] = 'Y'; + else + buf[0] = 'N'; + buf[1] = '\n'; + buf[2] = 0x00; + return simple_read_from_buffer(user_buf, count, ppos, buf, 2); +} + +static ssize_t write_file_bool(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + char buf[32]; + 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; + + 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 = simple_open, + .llseek = default_llseek, +}; + +/** + * debugfs_create_bool - create a debugfs file that is used to read and write a boolean 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. + * + * This function creates a file in debugfs with the given name that + * contains the value of the variable @value. If the @mode variable is so + * set, it can be read from, and written to. + * + * 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_bool(const char *name, umode_t mode, + struct dentry *parent, u32 *value) +{ + return debugfs_create_file(name, mode, parent, value, &fops_bool); +} +EXPORT_SYMBOL_GPL(debugfs_create_bool); + +static ssize_t read_file_blob(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct debugfs_blob_wrapper *blob = file->private_data; + return simple_read_from_buffer(user_buf, count, ppos, blob->data, + blob->size); +} + +static const struct file_operations fops_blob = { + .read = read_file_blob, + .open = simple_open, + .llseek = default_llseek, +}; + +/** + * 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 + * directory dentry if set. If this parameter is %NULL, then the + * file will be created in the root of the debugfs filesystem. + * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer + * to the blob data and the size of the data. + * + * This function creates a file in debugfs with the given name that exports + * @blob->data as a binary blob. 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_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); + +#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 new file mode 100644 index 00000000..b80bc846 --- /dev/null +++ b/fs/debugfs/inode.c @@ -0,0 +1,691 @@ +/* + * 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. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 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. + * + */ + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/mount.h> +#include <linux/pagemap.h> +#include <linux/init.h> +#include <linux/kobject.h> +#include <linux/namei.h> +#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 0755 + +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) + +{ + struct inode *inode = new_inode(sb); + + if (inode) { + inode->i_ino = get_next_ino(); + inode->i_mode = mode; + 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 = fops ? fops : &debugfs_file_operations; + inode->i_private = data; + 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; + + /* directory inodes start off with i_nlink == 2 + * (for "." entry) */ + inc_nlink(inode); + break; + } + } + return inode; +} + +/* SMP-safe */ +static int debugfs_mknod(struct inode *dir, struct dentry *dentry, + umode_t mode, dev_t dev, void *data, + const struct file_operations *fops) +{ + struct inode *inode; + int error = -EPERM; + + if (dentry->d_inode) + return -EEXIST; + + inode = debugfs_get_inode(dir->i_sb, mode, dev, data, fops); + if (inode) { + d_instantiate(dentry, inode); + dget(dentry); + error = 0; + } + return error; +} + +static int debugfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode, + void *data, const struct file_operations *fops) +{ + int res; + + mode = (mode & (S_IRWXUGO | S_ISVTX)) | S_IFDIR; + res = debugfs_mknod(dir, dentry, mode, 0, data, fops); + if (!res) { + inc_nlink(dir); + fsnotify_mkdir(dir, dentry); + } + return res; +} + +static int debugfs_link(struct inode *dir, struct dentry *dentry, umode_t mode, + void *data, const struct file_operations *fops) +{ + mode = (mode & S_IALLUGO) | S_IFLNK; + return debugfs_mknod(dir, dentry, mode, 0, data, fops); +} + +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, data, fops); + if (!res) + fsnotify_create(dir, dentry); + return res; +} + +static inline int debugfs_positive(struct dentry *dentry) +{ + return dentry->d_inode && !d_unhashed(dentry); +} + +struct debugfs_mount_opts { + uid_t uid; + gid_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; + 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; + opts->uid = option; + break; + case Opt_gid: + if (match_octal(&args[0], &option)) + return -EINVAL; + opts->gid = option; + 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; + + 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 (opts->uid != 0) + seq_printf(m, ",uid=%u", opts->uid); + if (opts->gid != 0) + seq_printf(m, ",gid=%u", 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; + + 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, + int flags, const char *dev_name, + void *data) +{ + return mount_single(fs_type, flags, data, debug_fill_super); +} + +static struct file_system_type debug_fs_type = { + .owner = THIS_MODULE, + .name = "debugfs", + .mount = debug_mount, + .kill_sb = kill_litter_super, +}; + +static int debugfs_create_by_name(const char *name, umode_t mode, + struct dentry *parent, + struct dentry **dentry, + void *data, + const struct file_operations *fops) +{ + int error = 0; + + /* 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) + 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)) { + switch (mode & S_IFMT) { + case S_IFDIR: + error = debugfs_mkdir(parent->d_inode, *dentry, mode, + data, fops); + break; + case S_IFLNK: + error = debugfs_link(parent->d_inode, *dentry, mode, + data, fops); + break; + default: + error = debugfs_create(parent->d_inode, *dentry, mode, + data, fops); + break; + } + dput(*dentry); + } else + error = PTR_ERR(*dentry); + mutex_unlock(&parent->d_inode->i_mutex); + + return error; +} + +/** + * 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. + * @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 + * 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 + * the open() call. + * @fops: a pointer to a struct file_operations that should be used for + * this file. + * + * This is the basic "create a file" function for debugfs. It allows for a + * 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 + * 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. + */ +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; + } +exit: + return dentry; +} +EXPORT_SYMBOL_GPL(debugfs_create_file); + +/** + * debugfs_create_dir - create a directory in the debugfs filesystem + * @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 will be created in the root of the debugfs filesystem. + * + * This function creates a directory in debugfs with the given name. + * + * 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. + */ +struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) +{ + return debugfs_create_file(name, + S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO, + parent, NULL, NULL); +} +EXPORT_SYMBOL_GPL(debugfs_create_dir); + +/** + * debugfs_create_symlink- create a symbolic link in the debugfs filesystem + * @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, + * 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 + * symbolic link. + * + * This function creates a symbolic link with the given name in debugfs that + * links to the given target path. + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the debugfs_remove() function when the symbolic + * link 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. + */ +struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, + const char *target) +{ + struct dentry *result; + char *link; + + link = kstrdup(target, GFP_KERNEL); + if (!link) + return NULL; + + result = debugfs_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 + * removed. + * + * This function removes a file or directory 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(struct dentry *dentry) +{ + struct dentry *parent; + int ret; + + if (!dentry) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + return; + + mutex_lock(&parent->d_inode->i_mutex); + 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; + struct dentry *parent; + + if (!dentry) + return; + + parent = dentry->d_parent; + if (!parent || !parent->d_inode) + return; + + parent = dentry; + mutex_lock(&parent->d_inode->i_mutex); + + 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. + */ + if (!list_empty(&child->d_subdirs)) { + mutex_unlock(&parent->d_inode->i_mutex); + parent = child; + mutex_lock(&parent->d_inode->i_mutex); + continue; + } + __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); + } + + parent = dentry->d_parent; + mutex_lock(&parent->d_inode->i_mutex); + __debugfs_remove(dentry, parent); + mutex_unlock(&parent->d_inode->i_mutex); + simple_release_fs(&debugfs_mount, &debugfs_mount_count); +} +EXPORT_SYMBOL_GPL(debugfs_remove_recursive); + +/** + * 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. + * + * 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, %NULL will be + * returned. + * + * 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 error; + struct dentry *dentry = NULL, *trap; + const char *old_name; + + trap = lock_rename(new_dir, old_dir); + /* Source or destination directories don't exist? */ + if (!old_dir->d_inode || !new_dir->d_inode) + goto exit; + /* Source does not exist, cyclic rename, or mountpoint? */ + if (!old_dentry->d_inode || 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 || dentry->d_inode) + goto exit; + + old_name = fsnotify_oldname_init(old_dentry->d_name.name); + + error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, + dentry); + if (error) { + fsnotify_oldname_free(old_name); + goto exit; + } + d_move(old_dentry, dentry); + fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, + S_ISDIR(old_dentry->d_inode->i_mode), + NULL, old_dentry); + fsnotify_oldname_free(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); + return NULL; +} +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) +{ + int retval; + + debug_kobj = kobject_create_and_add("debug", kernel_kobj); + if (!debug_kobj) + return -EINVAL; + + retval = register_filesystem(&debug_fs_type); + if (retval) + kobject_put(debug_kobj); + else + debugfs_registered = true; + + return retval; +} +core_initcall(debugfs_init); + |