debugfs: Add support to print u32 array in debugfs

Move the code from Xen to debugfs to make the code common
for other users as well.

Accked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
[v1: Fixed rebase issues]
[v2: Fixed PPC compile issues]
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Srivatsa Vaddagiri 2012-03-23 13:36:28 +05:30 committed by Konrad Rzeszutek Wilk
parent e816b57a33
commit 9fe2a70153
5 changed files with 145 additions and 114 deletions

View File

@ -19,107 +19,3 @@ struct dentry * __init xen_init_debugfs(void)
return d_xen_debug;
}
struct array_data
{
void *array;
unsigned elements;
};
static int u32_array_open(struct inode *inode, struct file *file)
{
file->private_data = NULL;
return nonseekable_open(inode, file);
}
static size_t format_array(char *buf, size_t bufsize, const char *fmt,
u32 *array, unsigned array_size)
{
size_t ret = 0;
unsigned i;
for(i = 0; i < array_size; i++) {
size_t len;
len = snprintf(buf, bufsize, fmt, array[i]);
len++; /* ' ' or '\n' */
ret += len;
if (buf) {
buf += len;
bufsize -= len;
buf[-1] = (i == array_size-1) ? '\n' : ' ';
}
}
ret++; /* \0 */
if (buf)
*buf = '\0';
return ret;
}
static char *format_array_alloc(const char *fmt, u32 *array, unsigned array_size)
{
size_t len = format_array(NULL, 0, fmt, array, array_size);
char *ret;
ret = kmalloc(len, GFP_KERNEL);
if (ret == NULL)
return NULL;
format_array(ret, len, fmt, array, array_size);
return ret;
}
static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct array_data *data = inode->i_private;
size_t size;
if (*ppos == 0) {
if (file->private_data) {
kfree(file->private_data);
file->private_data = NULL;
}
file->private_data = format_array_alloc("%u", data->array, data->elements);
}
size = 0;
if (file->private_data)
size = strlen(file->private_data);
return simple_read_from_buffer(buf, len, ppos, file->private_data, size);
}
static int xen_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= xen_array_release,
.read = u32_array_read,
.llseek = no_llseek,
};
struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, unsigned elements)
{
struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return NULL;
data->array = array;
data->elements = elements;
return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
}

View File

@ -3,8 +3,4 @@
struct dentry * __init xen_init_debugfs(void);
struct dentry *xen_debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, unsigned elements);
#endif /* _XEN_DEBUGFS_H */

View File

@ -440,12 +440,12 @@ static int __init xen_spinlock_debugfs(void)
debugfs_create_u64("time_total", 0444, d_spin_debug,
&spinlock_stats.time_total);
xen_debugfs_create_u32_array("histo_total", 0444, d_spin_debug,
spinlock_stats.histo_spin_total, HISTO_BUCKETS + 1);
xen_debugfs_create_u32_array("histo_spinning", 0444, d_spin_debug,
spinlock_stats.histo_spin_spinning, HISTO_BUCKETS + 1);
xen_debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug,
spinlock_stats.histo_spin_blocked, HISTO_BUCKETS + 1);
debugfs_create_u32_array("histo_total", 0444, d_spin_debug,
spinlock_stats.histo_spin_total, HISTO_BUCKETS + 1);
debugfs_create_u32_array("histo_spinning", 0444, d_spin_debug,
spinlock_stats.histo_spin_spinning, HISTO_BUCKETS + 1);
debugfs_create_u32_array("histo_blocked", 0444, d_spin_debug,
spinlock_stats.histo_spin_blocked, HISTO_BUCKETS + 1);
return 0;
}

View File

@ -20,6 +20,7 @@
#include <linux/namei.h>
#include <linux/debugfs.h>
#include <linux/io.h>
#include <linux/slab.h>
static ssize_t default_read_file(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
@ -520,6 +521,133 @@ struct dentry *debugfs_create_blob(const char *name, umode_t mode,
}
EXPORT_SYMBOL_GPL(debugfs_create_blob);
struct array_data {
void *array;
u32 elements;
};
static int u32_array_open(struct inode *inode, struct file *file)
{
file->private_data = NULL;
return nonseekable_open(inode, file);
}
static size_t format_array(char *buf, size_t bufsize, const char *fmt,
u32 *array, u32 array_size)
{
size_t ret = 0;
u32 i;
for (i = 0; i < array_size; i++) {
size_t len;
len = snprintf(buf, bufsize, fmt, array[i]);
len++; /* ' ' or '\n' */
ret += len;
if (buf) {
buf += len;
bufsize -= len;
buf[-1] = (i == array_size-1) ? '\n' : ' ';
}
}
ret++; /* \0 */
if (buf)
*buf = '\0';
return ret;
}
static char *format_array_alloc(const char *fmt, u32 *array,
u32 array_size)
{
size_t len = format_array(NULL, 0, fmt, array, array_size);
char *ret;
ret = kmalloc(len, GFP_KERNEL);
if (ret == NULL)
return NULL;
format_array(ret, len, fmt, array, array_size);
return ret;
}
static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
loff_t *ppos)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct array_data *data = inode->i_private;
size_t size;
if (*ppos == 0) {
if (file->private_data) {
kfree(file->private_data);
file->private_data = NULL;
}
file->private_data = format_array_alloc("%u", data->array,
data->elements);
}
size = 0;
if (file->private_data)
size = strlen(file->private_data);
return simple_read_from_buffer(buf, len, ppos,
file->private_data, size);
}
static int u32_array_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
static const struct file_operations u32_array_fops = {
.owner = THIS_MODULE,
.open = u32_array_open,
.release = u32_array_release,
.read = u32_array_read,
.llseek = no_llseek,
};
/**
* debugfs_create_u32_array - create a debugfs file that is used to read u32
* array.
* @name: a pointer to a string containing the name of the file to create.
* @mode: the permission that the file should have.
* @parent: a pointer to the parent dentry for this file. This should be a
* directory dentry if set. If this parameter is %NULL, then the
* file will be created in the root of the debugfs filesystem.
* @array: u32 array that provides data.
* @elements: total number of elements in the array.
*
* This function creates a file in debugfs with the given name that exports
* @array as data. If the @mode variable is so set it can be read from.
* Writing is not supported. Seek within the file is also not supported.
* Once array is created its size can not be changed.
*
* The function returns a pointer to dentry on success. If debugfs is not
* enabled in the kernel, the value -%ENODEV will be returned.
*/
struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, u32 elements)
{
struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
if (data == NULL)
return NULL;
data->array = array;
data->elements = elements;
return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
}
EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
#ifdef CONFIG_HAS_IOMEM
/*

View File

@ -93,6 +93,10 @@ struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
int nregs, void __iomem *base, char *prefix);
struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, u32 elements);
bool debugfs_initialized(void);
#else
@ -219,6 +223,13 @@ static inline bool debugfs_initialized(void)
return false;
}
static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
u32 *array, u32 elements)
{
return ERR_PTR(-ENODEV);
}
#endif
#endif