v4.19.13 snapshot.
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
new file mode 100644
index 0000000..4fce1da
--- /dev/null
+++ b/fs/debugfs/file.c
@@ -0,0 +1,1173 @@
+// 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.
+ *
+ * debugfs is for people to use instead of /proc or /sys.
+ * 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/debugfs.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/atomic.h>
+#include <linux/device.h>
+#include <linux/poll.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)
+{
+ 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_noop_file_operations = {
+ .read = default_read_file,
+ .write = default_write_file,
+ .open = simple_open,
+ .llseek = noop_llseek,
+};
+
+#define F_DENTRY(filp) ((filp)->f_path.dentry)
+
+const struct file_operations *debugfs_real_fops(const struct file *filp)
+{
+ struct debugfs_fsdata *fsd = F_DENTRY(filp)->d_fsdata;
+
+ if ((unsigned long)fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT) {
+ /*
+ * Urgh, we've been called w/o a protecting
+ * debugfs_file_get().
+ */
+ WARN_ON(1);
+ return NULL;
+ }
+
+ return fsd->real_fops;
+}
+EXPORT_SYMBOL_GPL(debugfs_real_fops);
+
+/**
+ * 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)
+{
+ struct debugfs_fsdata *fsd;
+ void *d_fsd;
+
+ d_fsd = READ_ONCE(dentry->d_fsdata);
+ if (!((unsigned long)d_fsd & DEBUGFS_FSDATA_IS_REAL_FOPS_BIT)) {
+ fsd = d_fsd;
+ } else {
+ fsd = kmalloc(sizeof(*fsd), GFP_KERNEL);
+ if (!fsd)
+ return -ENOMEM;
+
+ fsd->real_fops = (void *)((unsigned long)d_fsd &
+ ~DEBUGFS_FSDATA_IS_REAL_FOPS_BIT);
+ refcount_set(&fsd->active_users, 1);
+ init_completion(&fsd->active_users_drained);
+ if (cmpxchg(&dentry->d_fsdata, d_fsd, fsd) != d_fsd) {
+ kfree(fsd);
+ fsd = READ_ONCE(dentry->d_fsdata);
+ }
+ }
+
+ /*
+ * 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;
+}
+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);
+
+static int open_proxy_open(struct inode *inode, struct file *filp)
+{
+ struct dentry *dentry = F_DENTRY(filp);
+ const struct file_operations *real_fops = NULL;
+ int r;
+
+ r = debugfs_file_get(dentry);
+ if (r)
+ return r == -EIO ? -ENOENT : r;
+
+ real_fops = debugfs_real_fops(filp);
+ real_fops = fops_get(real_fops);
+ if (!real_fops) {
+ /* 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) \
+static ret_type full_proxy_ ## name(proto) \
+{ \
+ struct dentry *dentry = F_DENTRY(filp); \
+ const struct file_operations *real_fops; \
+ ret_type r; \
+ \
+ r = debugfs_file_get(dentry); \
+ if (unlikely(r)) \
+ return r; \
+ real_fops = debugfs_real_fops(filp); \
+ r = real_fops->name(args); \
+ debugfs_file_put(dentry); \
+ return r; \
+}
+
+FULL_PROXY_FUNC(llseek, loff_t, filp,
+ PROTO(struct file *filp, loff_t offset, int whence),
+ ARGS(filp, offset, whence));
+
+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));
+
+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));
+
+FULL_PROXY_FUNC(unlocked_ioctl, long, filp,
+ PROTO(struct file *filp, unsigned int cmd, unsigned long arg),
+ ARGS(filp, cmd, arg));
+
+static __poll_t full_proxy_poll(struct file *filp,
+ struct poll_table_struct *wait)
+{
+ struct dentry *dentry = F_DENTRY(filp);
+ __poll_t r = 0;
+ const struct file_operations *real_fops;
+
+ if (debugfs_file_get(dentry))
+ return EPOLLHUP;
+
+ real_fops = debugfs_real_fops(filp);
+ r = real_fops->poll(filp, wait);
+ debugfs_file_put(dentry);
+ return r;
+}
+
+static int full_proxy_release(struct inode *inode, struct file *filp)
+{
+ const struct dentry *dentry = F_DENTRY(filp);
+ const struct file_operations *real_fops = debugfs_real_fops(filp);
+ const struct file_operations *proxy_fops = filp->f_op;
+ 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, filp);
+
+ replace_fops(filp, d_inode(dentry)->i_fop);
+ kfree((void *)proxy_fops);
+ fops_put(real_fops);
+ return r;
+}
+
+static void __full_proxy_fops_init(struct file_operations *proxy_fops,
+ const struct file_operations *real_fops)
+{
+ proxy_fops->release = full_proxy_release;
+ if (real_fops->llseek)
+ proxy_fops->llseek = full_proxy_llseek;
+ if (real_fops->read)
+ proxy_fops->read = full_proxy_read;
+ if (real_fops->write)
+ proxy_fops->write = full_proxy_write;
+ if (real_fops->poll)
+ proxy_fops->poll = full_proxy_poll;
+ if (real_fops->unlocked_ioctl)
+ proxy_fops->unlocked_ioctl = full_proxy_unlocked_ioctl;
+}
+
+static int full_proxy_open(struct inode *inode, struct file *filp)
+{
+ struct dentry *dentry = F_DENTRY(filp);
+ const struct file_operations *real_fops = NULL;
+ struct file_operations *proxy_fops = NULL;
+ int r;
+
+ r = debugfs_file_get(dentry);
+ if (r)
+ return r == -EIO ? -ENOENT : r;
+
+ real_fops = debugfs_real_fops(filp);
+ real_fops = fops_get(real_fops);
+ if (!real_fops) {
+ /* 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;
+ }
+
+ proxy_fops = kzalloc(sizeof(*proxy_fops), GFP_KERNEL);
+ if (!proxy_fops) {
+ r = -ENOMEM;
+ goto free_proxy;
+ }
+ __full_proxy_fops_init(proxy_fops, real_fops);
+ replace_fops(filp, proxy_fops);
+
+ if (real_fops->open) {
+ r = real_fops->open(inode, filp);
+ if (r) {
+ replace_fops(filp, d_inode(dentry)->i_fop);
+ goto free_proxy;
+ } else if (filp->f_op != proxy_fops) {
+ /* No protection against file removal anymore. */
+ WARN(1, "debugfs file owner replaced proxy fops: %pd",
+ dentry);
+ goto free_proxy;
+ }
+ }
+
+ goto out;
+free_proxy:
+ kfree(proxy_fops);
+ fops_put(real_fops);
+out:
+ debugfs_file_put(dentry);
+ return r;
+}
+
+const struct file_operations debugfs_full_proxy_file_operations = {
+ .open = full_proxy_open,
+};
+
+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);
+
+ssize_t debugfs_attr_write(struct file *file, const 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_write(file, buf, len, ppos);
+ debugfs_file_put(dentry);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(debugfs_attr_write);
+
+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;
+ return 0;
+}
+static int debugfs_u8_get(void *data, u64 *val)
+{
+ *val = *(u8 *)data;
+ return 0;
+}
+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
+ * @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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u8,
+ &fops_u8_ro, &fops_u8_wo);
+}
+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_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
+ * @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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u16,
+ &fops_u16_ro, &fops_u16_wo);
+}
+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_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
+ * @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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u32,
+ &fops_u32_ro, &fops_u32_wo);
+}
+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_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
+ * @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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u64,
+ &fops_u64_ro, &fops_u64_wo);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_u64);
+
+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.
+ *
+ * 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_ulong(const char *name, umode_t mode,
+ struct dentry *parent, unsigned long *value)
+{
+ return 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_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_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_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
+ *
+ * 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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x8,
+ &fops_x8_ro, &fops_x8_wo);
+}
+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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x16,
+ &fops_x16_ro, &fops_x16_wo);
+}
+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)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_x32,
+ &fops_x32_ro, &fops_x32_wo);
+}
+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_mode_unsafe(name, mode, parent, value, &fops_x64,
+ &fops_x64_ro, &fops_x64_wo);
+}
+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_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
+ * @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_mode_unsafe(name, mode, parent, value,
+ &fops_size_t, &fops_size_t_ro,
+ &fops_size_t_wo);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_size_t);
+
+static int debugfs_atomic_t_set(void *data, u64 val)
+{
+ atomic_set((atomic_t *)data, val);
+ return 0;
+}
+static int debugfs_atomic_t_get(void *data, u64 *val)
+{
+ *val = atomic_read((atomic_t *)data);
+ return 0;
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
+ debugfs_atomic_t_set, "%lld\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_ro, debugfs_atomic_t_get, NULL,
+ "%lld\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set,
+ "%lld\n");
+
+/**
+ * debugfs_create_atomic_t - create a debugfs file that is used to read and
+ * write an atomic_t value
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @value: a pointer to the variable that the file should read to and write
+ * from.
+ */
+struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
+ struct dentry *parent, atomic_t *value)
+{
+ return 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);
+
+ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ char buf[3];
+ 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);
+
+ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ bool bv;
+ 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 = 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,
+};
+
+/**
+ * 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, bool *value)
+{
+ return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_bool,
+ &fops_bool_ro, &fops_bool_wo);
+}
+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;
+ 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 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_unsafe(name, mode, parent, blob, &fops_blob);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_blob);
+
+struct array_data {
+ void *array;
+ u32 elements;
+};
+
+static size_t u32_format_array(char *buf, size_t bufsize,
+ u32 *array, int array_size)
+{
+ size_t ret = 0;
+
+ while (--array_size >= 0) {
+ size_t len;
+ char term = array_size ? ' ' : '\n';
+
+ len = snprintf(buf, bufsize, "%u%c", *array++, term);
+ ret += len;
+
+ buf += len;
+ bufsize -= len;
+ }
+ return ret;
+}
+
+static int u32_array_open(struct inode *inode, struct file *file)
+{
+ struct array_data *data = inode->i_private;
+ int size, elements = data->elements;
+ char *buf;
+
+ /*
+ * Max size:
+ * - 10 digits + ' '/'\n' = 11 bytes per number
+ * - terminating NUL character
+ */
+ size = elements*11;
+ buf = kmalloc(size+1, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ buf[size] = 0;
+
+ file->private_data = buf;
+ u32_format_array(buf, size, data->array, data->elements);
+
+ return nonseekable_open(inode, file);
+}
+
+static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
+ loff_t *ppos)
+{
+ size_t size = strlen(file->private_data);
+
+ return simple_read_from_buffer(buf, len, ppos,
+ file->private_data, size);
+}
+
+static int u32_array_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+
+ return 0;
+}
+
+static const struct file_operations u32_array_fops = {
+ .owner = THIS_MODULE,
+ .open = u32_array_open,
+ .release = u32_array_release,
+ .read = u32_array_read,
+ .llseek = no_llseek,
+};
+
+/**
+ * debugfs_create_u32_array - create a debugfs file that is used to read u32
+ * array.
+ * @name: a pointer to a string containing the name of the file to create.
+ * @mode: the permission that the file should have.
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is %NULL, then the
+ * file will be created in the root of the debugfs filesystem.
+ * @array: u32 array that provides data.
+ * @elements: total number of elements in the array.
+ *
+ * This function creates a file in debugfs with the given name that exports
+ * @array as data. If the @mode variable is so set it can be read from.
+ * Writing is not supported. Seek within the file is also not supported.
+ * Once array is created its size can not be changed.
+ *
+ * The function returns a pointer to dentry on success. If debugfs is not
+ * enabled in the kernel, the value -%ENODEV will be returned.
+ */
+struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
+ struct dentry *parent,
+ u32 *array, u32 elements)
+{
+ struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
+
+ if (data == NULL)
+ return NULL;
+
+ data->array = array;
+ data->elements = elements;
+
+ return debugfs_create_file_unsafe(name, mode, parent, data,
+ &u32_array_fops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
+
+#ifdef CONFIG_HAS_IOMEM
+
+/*
+ * The regset32 stuff is used to print 32-bit registers using the
+ * seq_file utilities. We offer printing a register set in an already-opened
+ * sequential file or create a debugfs file that only prints a regset32.
+ */
+
+/**
+ * debugfs_print_regs32 - use seq_print to describe a set of registers
+ * @s: the seq_file structure being used to generate output
+ * @regs: an array if struct debugfs_reg32 structures
+ * @nregs: the length of the above array
+ * @base: the base address to be used in reading the registers
+ * @prefix: a string to be prefixed to every output line
+ *
+ * This function outputs a text block describing the current values of
+ * some 32-bit hardware registers. It is meant to be used within debugfs
+ * files based on seq_file that need to show registers, intermixed with other
+ * information. The prefix argument may be used to specify a leading string,
+ * because some peripherals have several blocks of identical registers,
+ * for example configuration of dma channels
+ */
+void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
+ int nregs, void __iomem *base, char *prefix)
+{
+ int i;
+
+ for (i = 0; i < nregs; i++, regs++) {
+ if (prefix)
+ seq_printf(s, "%s", prefix);
+ seq_printf(s, "%s = 0x%08x\n", regs->name,
+ readl(base + regs->offset));
+ if (seq_has_overflowed(s))
+ break;
+ }
+}
+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 */
+
+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.
+ */
+struct dentry *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 ERR_PTR(-ENOENT);
+
+ entry = devm_kzalloc(dev, sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return ERR_PTR(-ENOMEM);
+
+ entry->read = read_fn;
+ entry->dev = dev;
+
+ return debugfs_create_file(name, S_IRUGO, parent, entry,
+ &debugfs_devm_entry_ops);
+}
+EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile);
+