sys_swapon: separate swap_info allocation
Move the swap_info allocation to its own function. Only code movement,
no functional changes.
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Tested-by: Eric B Munson <emunson@mgebm.net>
Acked-by: Eric B Munson <emunson@mgebm.net>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 5238d8d..6d1c3c6 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1844,33 +1844,15 @@
late_initcall(max_swapfiles_check);
#endif
-SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
+static struct swap_info_struct *alloc_swap_info(void)
{
struct swap_info_struct *p;
- char *name = NULL;
- struct block_device *bdev = NULL;
- struct file *swap_file = NULL;
- struct address_space *mapping;
unsigned int type;
- int i, prev;
int error;
- union swap_header *swap_header;
- unsigned int nr_good_pages;
- int nr_extents = 0;
- sector_t span;
- unsigned long maxpages;
- unsigned long swapfilepages;
- unsigned char *swap_map = NULL;
- struct page *page = NULL;
- struct inode *inode = NULL;
- int did_down = 0;
-
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
spin_lock(&swap_lock);
for (type = 0; type < nr_swapfiles; type++) {
@@ -1906,6 +1888,41 @@
p->next = -1;
spin_unlock(&swap_lock);
+ return p;
+
+out:
+ return ERR_PTR(error);
+}
+
+SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
+{
+ struct swap_info_struct *p;
+ char *name = NULL;
+ struct block_device *bdev = NULL;
+ struct file *swap_file = NULL;
+ struct address_space *mapping;
+ int i, prev;
+ int error;
+ union swap_header *swap_header;
+ unsigned int nr_good_pages;
+ int nr_extents = 0;
+ sector_t span;
+ unsigned long maxpages;
+ unsigned long swapfilepages;
+ unsigned char *swap_map = NULL;
+ struct page *page = NULL;
+ struct inode *inode = NULL;
+ int did_down = 0;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ p = alloc_swap_info();
+ if (IS_ERR(p)) {
+ error = PTR_ERR(p);
+ goto out;
+ }
+
name = getname(specialfile);
error = PTR_ERR(name);
if (IS_ERR(name)) {