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>

3 files changed, 6 insertions, 114 deletions

diff --git a/arch/x86/xen/debugfs.c b/arch/x86/xen/debugfs.c
index ef1db1900d86..c8377fb26cdf 100644
--- a/arch/x86/xen/debugfs.c
+++ b/arch/x86/xen/debugfs.c
@@ -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);
-}
diff --git a/arch/x86/xen/debugfs.h b/arch/x86/xen/debugfs.h
index 78d25499be5b..12ebf3325c7b 100644
--- a/arch/x86/xen/debugfs.h
+++ b/arch/x86/xen/debugfs.h
@@ -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 */
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index d69cc6c3f808..83e866d714ce 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -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;
 }