1 files changed, 18 insertions, 10 deletions

diff --git a/fs/configfs/file.c b/fs/configfs/file.c
index 3527c7c6def8..a3658f9a082c 100644
--- a/fs/configfs/file.c
+++ b/fs/configfs/file.c
@@ -27,19 +27,26 @@
 #include <linux/fs.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/mutex.h>
 #include <asm/uaccess.h>
-#include <asm/semaphore.h>
 
 #include <linux/configfs.h>
 #include "configfs_internal.h"
 
+/*
+ * A simple attribute can only be 4096 characters.  Why 4k?  Because the
+ * original code limited it to PAGE_SIZE.  That's a bad idea, though,
+ * because an attribute of 16k on ia64 won't work on x86.  So we limit to
+ * 4k, our minimum common page size.
+ */
+#define SIMPLE_ATTR_SIZE 4096
 
 struct configfs_buffer {
         size_t                  count;
         loff_t                  pos;
         char                    * page;
         struct configfs_item_operations * ops;
-        struct semaphore        sem;
+        struct mutex            mutex;
         int                     needs_read_fill;
 };
 
@@ -69,7 +76,7 @@ static int fill_read_buffer(struct dentry * dentry, struct configfs_buffer * buf
 
         count = ops->show_attribute(item,attr,buffer->page);
         buffer->needs_read_fill = 0;
-        BUG_ON(count > (ssize_t)PAGE_SIZE);
+        BUG_ON(count > (ssize_t)SIMPLE_ATTR_SIZE);
         if (count >= 0)
                 buffer->count = count;
         else
@@ -102,7 +109,7 @@ configfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *pp
         struct configfs_buffer * buffer = file->private_data;
         ssize_t retval = 0;
 
-        down(&buffer->sem);
+        mutex_lock(&buffer->mutex);
         if (buffer->needs_read_fill) {
                 if ((retval = fill_read_buffer(file->f_path.dentry,buffer)))
                         goto out;
@@ -112,7 +119,7 @@ configfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *pp
         retval = simple_read_from_buffer(buf, count, ppos, buffer->page,
                                          buffer->count);
 out:
-        up(&buffer->sem);
+        mutex_unlock(&buffer->mutex);
         return retval;
 }
 
@@ -137,8 +144,8 @@ fill_write_buffer(struct configfs_buffer * buffer, const char __user * buf, size
         if (!buffer->page)
                 return -ENOMEM;
 
-        if (count >= PAGE_SIZE)
-                count = PAGE_SIZE - 1;
+        if (count >= SIMPLE_ATTR_SIZE)
+                count = SIMPLE_ATTR_SIZE - 1;
         error = copy_from_user(buffer->page,buf,count);
         buffer->needs_read_fill = 1;
         /* if buf is assumed to contain a string, terminate it by \0,
@@ -193,13 +200,13 @@ configfs_write_file(struct file *file, const char __user *buf, size_t count, lof
         struct configfs_buffer * buffer = file->private_data;
         ssize_t len;
 
-        down(&buffer->sem);
+        mutex_lock(&buffer->mutex);
         len = fill_write_buffer(buffer, buf, count);
         if (len > 0)
                 len = flush_write_buffer(file->f_path.dentry, buffer, count);
         if (len > 0)
                 *ppos += len;
-        up(&buffer->sem);
+        mutex_unlock(&buffer->mutex);
         return len;
 }
 
@@ -253,7 +260,7 @@ static int check_perm(struct inode * inode, struct file * file)
                 error = -ENOMEM;
                 goto Enomem;
         }
-        init_MUTEX(&buffer->sem);
+        mutex_init(&buffer->mutex);
         buffer->needs_read_fill = 1;
         buffer->ops = ops;
         file->private_data = buffer;
@@ -292,6 +299,7 @@ static int configfs_release(struct inode * inode, struct file * filp)
         if (buffer) {
                 if (buffer->page)
                         free_page((unsigned long)buffer->page);
+                mutex_destroy(&buffer->mutex);
                 kfree(buffer);
         }
         return 0;