diff options
Diffstat (limited to 'fs/debugfs/file.c')
| -rw-r--r-- | fs/debugfs/file.c | 1213 |
1 files changed, 941 insertions, 272 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index 63146295153b..3ec3324c2060 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -1,27 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 /* * 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. - * + * See Documentation/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> +#include <linux/device.h> +#include <linux/pm_runtime.h> +#include <linux/poll.h> +#include <linux/security.h> + +#include "internal.h" + +struct poll_table_struct; static ssize_t default_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) @@ -35,24 +38,543 @@ static ssize_t default_write_file(struct file *file, const char __user *buf, return count; } -const struct file_operations debugfs_file_operations = { +const struct file_operations debugfs_noop_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) +#define F_DENTRY(filp) ((filp)->f_path.dentry) + +void *debugfs_get_aux(const struct file *file) +{ + return DEBUGFS_I(file_inode(file))->aux; +} +EXPORT_SYMBOL_GPL(debugfs_get_aux); + +enum dbgfs_get_mode { + DBGFS_GET_ALREADY, + DBGFS_GET_REGULAR, + DBGFS_GET_SHORT, +}; + +static int __debugfs_file_get(struct dentry *dentry, enum dbgfs_get_mode mode) +{ + struct debugfs_fsdata *fsd; + void *d_fsd; + + /* + * This could only happen if some debugfs user erroneously calls + * debugfs_file_get() on a dentry that isn't even a file, let + * them know about it. + */ + if (WARN_ON(!d_is_reg(dentry))) + return -EINVAL; + + d_fsd = READ_ONCE(dentry->d_fsdata); + if (d_fsd) { + fsd = d_fsd; + } else { + struct inode *inode = dentry->d_inode; + unsigned int methods = 0; + + if (WARN_ON(mode == DBGFS_GET_ALREADY)) + return -EINVAL; + + fsd = kmalloc(sizeof(*fsd), GFP_KERNEL); + if (!fsd) + return -ENOMEM; + + if (mode == DBGFS_GET_SHORT) { + const struct debugfs_short_fops *ops; + ops = fsd->short_fops = DEBUGFS_I(inode)->short_fops; + if (ops->llseek) + methods |= HAS_LSEEK; + if (ops->read) + methods |= HAS_READ; + if (ops->write) + methods |= HAS_WRITE; + fsd->real_fops = NULL; + } else { + const struct file_operations *ops; + ops = fsd->real_fops = DEBUGFS_I(inode)->real_fops; + if (ops->llseek) + methods |= HAS_LSEEK; + if (ops->read) + methods |= HAS_READ; + if (ops->write) + methods |= HAS_WRITE; + if (ops->unlocked_ioctl) + methods |= HAS_IOCTL; + if (ops->poll) + methods |= HAS_POLL; + fsd->short_fops = NULL; + } + fsd->methods = methods; + refcount_set(&fsd->active_users, 1); + init_completion(&fsd->active_users_drained); + INIT_LIST_HEAD(&fsd->cancellations); + mutex_init(&fsd->cancellations_mtx); + + d_fsd = cmpxchg(&dentry->d_fsdata, NULL, fsd); + if (d_fsd) { + mutex_destroy(&fsd->cancellations_mtx); + kfree(fsd); + fsd = d_fsd; + } + } + + /* + * In case of a successful cmpxchg() above, this check is + * strictly necessary and must follow it, see the comment in + * __debugfs_remove_file(). + * OTOH, if the cmpxchg() hasn't been executed or wasn't + * successful, this serves the purpose of not starving + * removers. + */ + if (d_unlinked(dentry)) + return -EIO; + + if (!refcount_inc_not_zero(&fsd->active_users)) + return -EIO; + + return 0; +} + +/** + * debugfs_file_get - mark the beginning of file data access + * @dentry: the dentry object whose data is being accessed. + * + * Up to a matching call to debugfs_file_put(), any successive call + * into the file removing functions debugfs_remove() and + * debugfs_remove_recursive() will block. Since associated private + * file data may only get freed after a successful return of any of + * the removal functions, you may safely access it after a successful + * call to debugfs_file_get() without worrying about lifetime issues. + * + * If -%EIO is returned, the file has already been removed and thus, + * it is not safe to access any of its data. If, on the other hand, + * it is allowed to access the file data, zero is returned. + */ +int debugfs_file_get(struct dentry *dentry) +{ + return __debugfs_file_get(dentry, DBGFS_GET_ALREADY); +} +EXPORT_SYMBOL_GPL(debugfs_file_get); + +/** + * debugfs_file_put - mark the end of file data access + * @dentry: the dentry object formerly passed to + * debugfs_file_get(). + * + * Allow any ongoing concurrent call into debugfs_remove() or + * debugfs_remove_recursive() blocked by a former call to + * debugfs_file_get() to proceed and return to its caller. + */ +void debugfs_file_put(struct dentry *dentry) +{ + struct debugfs_fsdata *fsd = READ_ONCE(dentry->d_fsdata); + + if (refcount_dec_and_test(&fsd->active_users)) + complete(&fsd->active_users_drained); +} +EXPORT_SYMBOL_GPL(debugfs_file_put); + +/** + * debugfs_enter_cancellation - enter a debugfs cancellation + * @file: the file being accessed + * @cancellation: the cancellation object, the cancel callback + * inside of it must be initialized + * + * When a debugfs file is removed it needs to wait for all active + * operations to complete. However, the operation itself may need + * to wait for hardware or completion of some asynchronous process + * or similar. As such, it may need to be cancelled to avoid long + * waits or even deadlocks. + * + * This function can be used inside a debugfs handler that may + * need to be cancelled. As soon as this function is called, the + * cancellation's 'cancel' callback may be called, at which point + * the caller should proceed to call debugfs_leave_cancellation() + * and leave the debugfs handler function as soon as possible. + * Note that the 'cancel' callback is only ever called in the + * context of some kind of debugfs_remove(). + * + * This function must be paired with debugfs_leave_cancellation(). + */ +void debugfs_enter_cancellation(struct file *file, + struct debugfs_cancellation *cancellation) +{ + struct debugfs_fsdata *fsd; + struct dentry *dentry = F_DENTRY(file); + + INIT_LIST_HEAD(&cancellation->list); + + if (WARN_ON(!d_is_reg(dentry))) + return; + + if (WARN_ON(!cancellation->cancel)) + return; + + fsd = READ_ONCE(dentry->d_fsdata); + if (WARN_ON(!fsd)) + return; + + mutex_lock(&fsd->cancellations_mtx); + list_add(&cancellation->list, &fsd->cancellations); + mutex_unlock(&fsd->cancellations_mtx); + + /* if we're already removing wake it up to cancel */ + if (d_unlinked(dentry)) + complete(&fsd->active_users_drained); +} +EXPORT_SYMBOL_GPL(debugfs_enter_cancellation); + +/** + * debugfs_leave_cancellation - leave cancellation section + * @file: the file being accessed + * @cancellation: the cancellation previously registered with + * debugfs_enter_cancellation() + * + * See the documentation of debugfs_enter_cancellation(). + */ +void debugfs_leave_cancellation(struct file *file, + struct debugfs_cancellation *cancellation) +{ + struct debugfs_fsdata *fsd; + struct dentry *dentry = F_DENTRY(file); + + if (WARN_ON(!d_is_reg(dentry))) + return; + + fsd = READ_ONCE(dentry->d_fsdata); + if (WARN_ON(!fsd)) + return; + + mutex_lock(&fsd->cancellations_mtx); + if (!list_empty(&cancellation->list)) + list_del(&cancellation->list); + mutex_unlock(&fsd->cancellations_mtx); +} +EXPORT_SYMBOL_GPL(debugfs_leave_cancellation); + +/* + * Only permit access to world-readable files when the kernel is locked down. + * We also need to exclude any file that has ways to write or alter it as root + * can bypass the permissions check. + */ +static int debugfs_locked_down(struct inode *inode, + struct file *filp, + const struct file_operations *real_fops) +{ + if ((inode->i_mode & 07777 & ~0444) == 0 && + !(filp->f_mode & FMODE_WRITE) && + (!real_fops || + (!real_fops->unlocked_ioctl && + !real_fops->compat_ioctl && + !real_fops->mmap))) + return 0; + + if (security_locked_down(LOCKDOWN_DEBUGFS)) + return -EPERM; + + return 0; +} + +static int open_proxy_open(struct inode *inode, struct file *filp) +{ + struct dentry *dentry = F_DENTRY(filp); + const struct file_operations *real_fops = DEBUGFS_I(inode)->real_fops; + int r; + + r = __debugfs_file_get(dentry, DBGFS_GET_REGULAR); + if (r) + return r == -EIO ? -ENOENT : r; + + r = debugfs_locked_down(inode, filp, real_fops); + if (r) + goto out; + + if (!fops_get(real_fops)) { +#ifdef CONFIG_MODULES + if (real_fops->owner && + real_fops->owner->state == MODULE_STATE_GOING) { + r = -ENXIO; + goto out; + } +#endif + + /* Huh? Module did not clean up after itself at exit? */ + WARN(1, "debugfs file owner did not clean up at exit: %pd", + dentry); + r = -ENXIO; + goto out; + } + replace_fops(filp, real_fops); + + if (real_fops->open) + r = real_fops->open(inode, filp); + +out: + debugfs_file_put(dentry); + return r; +} + +const struct file_operations debugfs_open_proxy_file_operations = { + .open = open_proxy_open, +}; + +#define PROTO(args...) args +#define ARGS(args...) args + +#define FULL_PROXY_FUNC(name, ret_type, filp, proto, args, bit, ret) \ +static ret_type full_proxy_ ## name(proto) \ +{ \ + struct dentry *dentry = F_DENTRY(filp); \ + struct debugfs_fsdata *fsd = dentry->d_fsdata; \ + ret_type r; \ + \ + if (!(fsd->methods & bit)) \ + return ret; \ + r = debugfs_file_get(dentry); \ + if (unlikely(r)) \ + return r; \ + r = fsd->real_fops->name(args); \ + debugfs_file_put(dentry); \ + return r; \ +} + +#define SHORT_PROXY_FUNC(name, ret_type, filp, proto, args, bit, ret) \ +static ret_type short_proxy_ ## name(proto) \ +{ \ + struct dentry *dentry = F_DENTRY(filp); \ + struct debugfs_fsdata *fsd = dentry->d_fsdata; \ + ret_type r; \ + \ + if (!(fsd->methods & bit)) \ + return ret; \ + r = debugfs_file_get(dentry); \ + if (unlikely(r)) \ + return r; \ + r = fsd->short_fops->name(args); \ + debugfs_file_put(dentry); \ + return r; \ +} + +SHORT_PROXY_FUNC(llseek, loff_t, filp, + PROTO(struct file *filp, loff_t offset, int whence), + ARGS(filp, offset, whence), HAS_LSEEK, -ESPIPE); + +FULL_PROXY_FUNC(llseek, loff_t, filp, + PROTO(struct file *filp, loff_t offset, int whence), + ARGS(filp, offset, whence), HAS_LSEEK, -ESPIPE); + +SHORT_PROXY_FUNC(read, ssize_t, filp, + PROTO(struct file *filp, char __user *buf, size_t size, + loff_t *ppos), + ARGS(filp, buf, size, ppos), HAS_READ, -EINVAL); + +FULL_PROXY_FUNC(read, ssize_t, filp, + PROTO(struct file *filp, char __user *buf, size_t size, + loff_t *ppos), + ARGS(filp, buf, size, ppos), HAS_READ, -EINVAL); + +SHORT_PROXY_FUNC(write, ssize_t, filp, + PROTO(struct file *filp, const char __user *buf, + size_t size, loff_t *ppos), + ARGS(filp, buf, size, ppos), HAS_WRITE, -EINVAL); + +FULL_PROXY_FUNC(write, ssize_t, filp, + PROTO(struct file *filp, const char __user *buf, + size_t size, loff_t *ppos), + ARGS(filp, buf, size, ppos), HAS_WRITE, -EINVAL); + +FULL_PROXY_FUNC(unlocked_ioctl, long, filp, + PROTO(struct file *filp, unsigned int cmd, unsigned long arg), + ARGS(filp, cmd, arg), HAS_IOCTL, -ENOTTY); + +static __poll_t full_proxy_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct dentry *dentry = F_DENTRY(filp); + struct debugfs_fsdata *fsd = dentry->d_fsdata; + __poll_t r = 0; + + if (!(fsd->methods & HAS_POLL)) + return DEFAULT_POLLMASK; + if (debugfs_file_get(dentry)) + return EPOLLHUP; + + r = fsd->real_fops->poll(filp, wait); + debugfs_file_put(dentry); + return r; +} + +static int full_proxy_release(struct inode *inode, struct file *file) +{ + struct debugfs_fsdata *fsd = F_DENTRY(file)->d_fsdata; + const struct file_operations *real_fops = fsd->real_fops; + int r = 0; + + /* + * We must not protect this against removal races here: the + * original releaser should be called unconditionally in order + * not to leak any resources. Releasers must not assume that + * ->i_private is still being meaningful here. + */ + if (real_fops->release) + r = real_fops->release(inode, file); + + fops_put(real_fops); + return r; +} + +static int full_proxy_open_regular(struct inode *inode, struct file *filp) +{ + struct dentry *dentry = F_DENTRY(filp); + const struct file_operations *real_fops; + struct debugfs_fsdata *fsd; + int r; + + r = __debugfs_file_get(dentry, DBGFS_GET_REGULAR); + if (r) + return r == -EIO ? -ENOENT : r; + + fsd = dentry->d_fsdata; + real_fops = fsd->real_fops; + r = debugfs_locked_down(inode, filp, real_fops); + if (r) + goto out; + + if (!fops_get(real_fops)) { +#ifdef CONFIG_MODULES + if (real_fops->owner && + real_fops->owner->state == MODULE_STATE_GOING) { + r = -ENXIO; + goto out; + } +#endif + + /* Huh? Module did not cleanup after itself at exit? */ + WARN(1, "debugfs file owner did not clean up at exit: %pd", + dentry); + r = -ENXIO; + goto out; + } + + if (real_fops->open) { + r = real_fops->open(inode, filp); + if (r) { + fops_put(real_fops); + } else if (filp->f_op != &debugfs_full_proxy_file_operations) { + /* No protection against file removal anymore. */ + WARN(1, "debugfs file owner replaced proxy fops: %pd", + dentry); + fops_put(real_fops); + } + } +out: + debugfs_file_put(dentry); + return r; +} + +const struct file_operations debugfs_full_proxy_file_operations = { + .open = full_proxy_open_regular, + .release = full_proxy_release, + .llseek = full_proxy_llseek, + .read = full_proxy_read, + .write = full_proxy_write, + .poll = full_proxy_poll, + .unlocked_ioctl = full_proxy_unlocked_ioctl +}; + +static int full_proxy_open_short(struct inode *inode, struct file *filp) { - nd_set_link(nd, dentry->d_inode->i_private); - return NULL; + struct dentry *dentry = F_DENTRY(filp); + int r; + + r = __debugfs_file_get(dentry, DBGFS_GET_SHORT); + if (r) + return r == -EIO ? -ENOENT : r; + r = debugfs_locked_down(inode, filp, NULL); + if (!r) + r = simple_open(inode, filp); + debugfs_file_put(dentry); + return r; } -const struct inode_operations debugfs_link_operations = { - .readlink = generic_readlink, - .follow_link = debugfs_follow_link, +const struct file_operations debugfs_full_short_proxy_file_operations = { + .open = full_proxy_open_short, + .llseek = short_proxy_llseek, + .read = short_proxy_read, + .write = short_proxy_write, }; +ssize_t debugfs_attr_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + struct dentry *dentry = F_DENTRY(file); + ssize_t ret; + + ret = debugfs_file_get(dentry); + if (unlikely(ret)) + return ret; + ret = simple_attr_read(file, buf, len, ppos); + debugfs_file_put(dentry); + return ret; +} +EXPORT_SYMBOL_GPL(debugfs_attr_read); + +static ssize_t debugfs_attr_write_xsigned(struct file *file, const char __user *buf, + size_t len, loff_t *ppos, bool is_signed) +{ + struct dentry *dentry = F_DENTRY(file); + ssize_t ret; + + ret = debugfs_file_get(dentry); + if (unlikely(ret)) + return ret; + if (is_signed) + ret = simple_attr_write_signed(file, buf, len, ppos); + else + ret = simple_attr_write(file, buf, len, ppos); + debugfs_file_put(dentry); + return ret; +} + +ssize_t debugfs_attr_write(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + return debugfs_attr_write_xsigned(file, buf, len, ppos, false); +} +EXPORT_SYMBOL_GPL(debugfs_attr_write); + +ssize_t debugfs_attr_write_signed(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + return debugfs_attr_write_xsigned(file, buf, len, ppos, true); +} +EXPORT_SYMBOL_GPL(debugfs_attr_write_signed); + +static struct dentry *debugfs_create_mode_unsafe(const char *name, umode_t mode, + struct dentry *parent, void *value, + const struct file_operations *fops, + const struct file_operations *fops_ro, + const struct file_operations *fops_wo) +{ + /* if there are no write bits set, make read only */ + if (!(mode & S_IWUGO)) + return debugfs_create_file_unsafe(name, mode, parent, value, + fops_ro); + /* if there are no read bits set, make write only */ + if (!(mode & S_IRUGO)) + return debugfs_create_file_unsafe(name, mode, parent, value, + fops_wo); + + return debugfs_create_file_unsafe(name, mode, parent, value, fops); +} + static int debugfs_u8_set(void *data, u64 val) { *(u8 *)data = val; @@ -63,9 +585,9 @@ 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"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_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 @@ -80,28 +602,12 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n"); * 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) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u8, + &fops_u8_ro, &fops_u8_wo); } EXPORT_SYMBOL_GPL(debugfs_create_u8); @@ -115,9 +621,9 @@ 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"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_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 @@ -132,28 +638,12 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n"); * 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) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u16, + &fops_u16_ro, &fops_u16_wo); } EXPORT_SYMBOL_GPL(debugfs_create_u16); @@ -167,9 +657,9 @@ 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"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_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 @@ -184,28 +674,12 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n"); * 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) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u32, + &fops_u32_ro, &fops_u32_wo); } EXPORT_SYMBOL_GPL(debugfs_create_u32); @@ -220,9 +694,9 @@ 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"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_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 @@ -237,44 +711,72 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n"); * 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) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u64, + &fops_u64_ro, &fops_u64_wo); } 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"); +static int debugfs_ulong_set(void *data, u64 val) +{ + *(unsigned long *)data = val; + return 0; +} + +static int debugfs_ulong_get(void *data, u64 *val) +{ + *val = *(unsigned long *)data; + return 0; +} +DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong, debugfs_ulong_get, debugfs_ulong_set, + "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_ro, debugfs_ulong_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_ulong_wo, NULL, debugfs_ulong_set, "%llu\n"); + +/** + * debugfs_create_ulong - create a debugfs file that is used to read and write + * an unsigned long 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. + */ +void debugfs_create_ulong(const char *name, umode_t mode, struct dentry *parent, + unsigned long *value) +{ + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_ulong, + &fops_ulong_ro, &fops_ulong_wo); +} +EXPORT_SYMBOL_GPL(debugfs_create_ulong); + +DEFINE_DEBUGFS_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n"); +DEFINE_DEBUGFS_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_DEBUGFS_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, + "0x%04llx\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n"); +DEFINE_DEBUGFS_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_DEBUGFS_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, + "0x%08llx\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n"); +DEFINE_DEBUGFS_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"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, + "0x%016llx\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_x64_wo, NULL, 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 @@ -294,17 +796,11 @@ 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, umode_t mode, - struct dentry *parent, u8 *value) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x8, + &fops_x8_ro, &fops_x8_wo); } EXPORT_SYMBOL_GPL(debugfs_create_x8); @@ -318,17 +814,11 @@ 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, umode_t mode, - struct dentry *parent, u16 *value) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x16, + &fops_x16_ro, &fops_x16_wo); } EXPORT_SYMBOL_GPL(debugfs_create_x16); @@ -342,17 +832,11 @@ 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, umode_t mode, - struct dentry *parent, u32 *value) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x32, + &fops_x32_ro, &fops_x32_wo); } EXPORT_SYMBOL_GPL(debugfs_create_x32); @@ -366,10 +850,11 @@ 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, umode_t mode, - struct dentry *parent, u64 *value) +void debugfs_create_x64(const char *name, umode_t mode, struct dentry *parent, + u64 *value) { - return debugfs_create_file(name, mode, parent, value, &fops_x64); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x64, + &fops_x64_ro, &fops_x64_wo); } EXPORT_SYMBOL_GPL(debugfs_create_x64); @@ -384,8 +869,10 @@ 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 */ +DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set, + "%llu\n"); /* %llu and %zu are more or less the same */ +DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_ro, debugfs_size_t_get, NULL, "%llu\n"); +DEFINE_DEBUGFS_ATTRIBUTE(fops_size_t_wo, NULL, debugfs_size_t_set, "%llu\n"); /** * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value @@ -397,10 +884,11 @@ 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, umode_t mode, - struct dentry *parent, size_t *value) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_size_t, + &fops_size_t_ro, &fops_size_t_wo); } EXPORT_SYMBOL_GPL(debugfs_create_size_t); @@ -414,10 +902,12 @@ 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, +DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(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"); +DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(fops_atomic_t_ro, debugfs_atomic_t_get, NULL, + "%lld\n"); +DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(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 @@ -430,59 +920,73 @@ DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, "%lld\n"); * @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) +void 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); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_atomic_t, + &fops_atomic_t_ro, &fops_atomic_t_wo); } 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) +ssize_t debugfs_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) + char buf[2]; + bool val; + int r; + struct dentry *dentry = F_DENTRY(file); + + r = debugfs_file_get(dentry); + if (unlikely(r)) + return r; + val = *(bool *)file->private_data; + debugfs_file_put(dentry); + + 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); } +EXPORT_SYMBOL_GPL(debugfs_read_file_bool); -static ssize_t write_file_bool(struct file *file, const char __user *user_buf, - size_t count, loff_t *ppos) +ssize_t debugfs_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; - - buf[buf_size] = '\0'; - if (strtobool(buf, &bv) == 0) + int r; + bool *val = file->private_data; + struct dentry *dentry = F_DENTRY(file); + + r = kstrtobool_from_user(user_buf, count, &bv); + if (!r) { + r = debugfs_file_get(dentry); + if (unlikely(r)) + return r; *val = bv; + debugfs_file_put(dentry); + } return count; } +EXPORT_SYMBOL_GPL(debugfs_write_file_bool); static const struct file_operations fops_bool = { - .read = read_file_bool, - .write = write_file_bool, + .read = debugfs_read_file_bool, + .write = debugfs_write_file_bool, + .open = simple_open, + .llseek = default_llseek, +}; + +static const struct file_operations fops_bool_ro = { + .read = debugfs_read_file_bool, + .open = simple_open, + .llseek = default_llseek, +}; + +static const struct file_operations fops_bool_wo = { + .write = debugfs_write_file_bool, .open = simple_open, .llseek = default_llseek, }; @@ -500,40 +1004,185 @@ static const struct file_operations fops_bool = { * 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) +void debugfs_create_bool(const char *name, umode_t mode, struct dentry *parent, + bool *value) { - return debugfs_create_file(name, mode, parent, value, &fops_bool); + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_bool, + &fops_bool_ro, &fops_bool_wo); } EXPORT_SYMBOL_GPL(debugfs_create_bool); +ssize_t debugfs_read_file_str(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct dentry *dentry = F_DENTRY(file); + char *str, *copy = NULL; + int copy_len, len; + ssize_t ret; + + ret = debugfs_file_get(dentry); + if (unlikely(ret)) + return ret; + + str = *(char **)file->private_data; + len = strlen(str) + 1; + copy = kmalloc(len, GFP_KERNEL); + if (!copy) { + debugfs_file_put(dentry); + return -ENOMEM; + } + + copy_len = strscpy(copy, str, len); + debugfs_file_put(dentry); + if (copy_len < 0) { + kfree(copy); + return copy_len; + } + + copy[copy_len] = '\n'; + + ret = simple_read_from_buffer(user_buf, count, ppos, copy, len); + kfree(copy); + + return ret; +} +EXPORT_SYMBOL_GPL(debugfs_create_str); + +static ssize_t debugfs_write_file_str(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct dentry *dentry = F_DENTRY(file); + char *old, *new = NULL; + int pos = *ppos; + int r; + + r = debugfs_file_get(dentry); + if (unlikely(r)) + return r; + + old = *(char **)file->private_data; + + /* only allow strict concatenation */ + r = -EINVAL; + if (pos && pos != strlen(old)) + goto error; + + r = -E2BIG; + if (pos + count + 1 > PAGE_SIZE) + goto error; + + r = -ENOMEM; + new = kmalloc(pos + count + 1, GFP_KERNEL); + if (!new) + goto error; + + if (pos) + memcpy(new, old, pos); + + r = -EFAULT; + if (copy_from_user(new + pos, user_buf, count)) + goto error; + + new[pos + count] = '\0'; + strim(new); + + rcu_assign_pointer(*(char __rcu **)file->private_data, new); + synchronize_rcu(); + kfree(old); + + debugfs_file_put(dentry); + return count; + +error: + kfree(new); + debugfs_file_put(dentry); + return r; +} + +static const struct file_operations fops_str = { + .read = debugfs_read_file_str, + .write = debugfs_write_file_str, + .open = simple_open, + .llseek = default_llseek, +}; + +static const struct file_operations fops_str_ro = { + .read = debugfs_read_file_str, + .open = simple_open, + .llseek = default_llseek, +}; + +static const struct file_operations fops_str_wo = { + .write = debugfs_write_file_str, + .open = simple_open, + .llseek = default_llseek, +}; + +/** + * debugfs_create_str - create a debugfs file that is used to read and write a string 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. + */ +void debugfs_create_str(const char *name, umode_t mode, + struct dentry *parent, char **value) +{ + debugfs_create_mode_unsafe(name, mode, parent, value, &fops_str, + &fops_str_ro, &fops_str_wo); +} + 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); + struct dentry *dentry = F_DENTRY(file); + ssize_t r; + + r = debugfs_file_get(dentry); + if (unlikely(r)) + return r; + r = simple_read_from_buffer(user_buf, count, ppos, blob->data, + blob->size); + debugfs_file_put(dentry); + return r; +} + +static ssize_t write_file_blob(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct debugfs_blob_wrapper *blob = file->private_data; + struct dentry *dentry = F_DENTRY(file); + ssize_t r; + + r = debugfs_file_get(dentry); + if (unlikely(r)) + return r; + r = simple_write_to_buffer(blob->data, blob->size, ppos, user_buf, + count); + + debugfs_file_put(dentry); + return r; } static const struct file_operations fops_blob = { .read = read_file_blob, + .write = write_file_blob, .open = simple_open, .llseek = default_llseek, }; /** - * debugfs_create_blob - create a debugfs file that is used to read a binary blob + * debugfs_create_blob - create a debugfs file that is used to read and write + * 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 @@ -544,31 +1193,25 @@ static const struct file_operations fops_blob = { * * 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. + * 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. + * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) 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. + * If debugfs is not enabled in the kernel, the value ERR_PTR(-ENODEV) will + * be returned. */ 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); + return debugfs_create_file_unsafe(name, mode & 0644, 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) { @@ -589,8 +1232,8 @@ static size_t u32_format_array(char *buf, size_t bufsize, static int u32_array_open(struct inode *inode, struct file *file) { - struct array_data *data = inode->i_private; - int size, elements = data->elements; + struct debugfs_u32_array *data = inode->i_private; + int size, elements = data->n_elements; char *buf; /* @@ -605,7 +1248,7 @@ static int u32_array_open(struct inode *inode, struct file *file) buf[size] = 0; file->private_data = buf; - u32_format_array(buf, size, data->array, data->elements); + u32_format_array(buf, size, data->array, data->n_elements); return nonseekable_open(inode, file); } @@ -631,7 +1274,6 @@ static const struct file_operations u32_array_fops = { .open = u32_array_open, .release = u32_array_release, .read = u32_array_read, - .llseek = no_llseek, }; /** @@ -642,30 +1284,18 @@ static const struct file_operations u32_array_fops = { * @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. + * @array: wrapper struct containing data pointer and size of 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) +void debugfs_create_u32_array(const char *name, umode_t mode, + struct dentry *parent, + struct debugfs_u32_array *array) { - 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); + debugfs_create_file_unsafe(name, mode, parent, array, &u32_array_fops); } EXPORT_SYMBOL_GPL(debugfs_create_u32_array); @@ -692,40 +1322,38 @@ EXPORT_SYMBOL_GPL(debugfs_create_u32_array); * 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) +void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, + int nregs, void __iomem *base, char *prefix) { - int i, ret = 0; + int i; 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)); + seq_printf(s, "%s", prefix); + seq_printf(s, "%s = 0x%08x\n", regs->name, + readl(base + regs->offset)); + if (seq_has_overflowed(s)) + break; } - return ret; } EXPORT_SYMBOL_GPL(debugfs_print_regs32); -static int debugfs_show_regset32(struct seq_file *s, void *data) +static int debugfs_regset32_show(struct seq_file *s, void *data) { struct debugfs_regset32 *regset = s->private; + if (regset->dev) + pm_runtime_get_sync(regset->dev); + 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); + if (regset->dev) + pm_runtime_put(regset->dev); + + return 0; } -static const struct file_operations fops_regset32 = { - .open = debugfs_open_regset32, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; +DEFINE_SHOW_ATTRIBUTE(debugfs_regset32); /** * debugfs_create_regset32 - create a debugfs file that returns register values @@ -741,23 +1369,64 @@ static const struct file_operations fops_regset32 = { * 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) +void 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); + debugfs_create_file(name, mode, parent, regset, &debugfs_regset32_fops); } EXPORT_SYMBOL_GPL(debugfs_create_regset32); #endif /* CONFIG_HAS_IOMEM */ + +struct debugfs_devm_entry { + int (*read)(struct seq_file *seq, void *data); + struct device *dev; +}; + +static int debugfs_devm_entry_open(struct inode *inode, struct file *f) +{ + struct debugfs_devm_entry *entry = inode->i_private; + + return single_open(f, entry->read, entry->dev); +} + +static const struct file_operations debugfs_devm_entry_ops = { + .owner = THIS_MODULE, + .open = debugfs_devm_entry_open, + .release = single_release, + .read = seq_read, + .llseek = seq_lseek +}; + +/** + * debugfs_create_devm_seqfile - create a debugfs file that is bound to device. + * + * @dev: device related to this debugfs file. + * @name: name of the debugfs file. + * @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. + * @read_fn: function pointer called to print the seq_file content. + */ +void debugfs_create_devm_seqfile(struct device *dev, const char *name, + struct dentry *parent, + int (*read_fn)(struct seq_file *s, void *data)) +{ + struct debugfs_devm_entry *entry; + + if (IS_ERR(parent)) + return; + + entry = devm_kzalloc(dev, sizeof(*entry), GFP_KERNEL); + if (!entry) + return; + + entry->read = read_fn; + entry->dev = dev; + + debugfs_create_file(name, S_IRUGO, parent, entry, + &debugfs_devm_entry_ops); +} +EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile); |