[PATCH] md: simplify free_params for kmalloc vs vmalloc fallback

From: Michal Hocko
Date: Thu Apr 28 2016 - 10:51:33 EST


From: Michal Hocko <mhocko@xxxxxxxx>

Use kvfree rather than DM_PARAMS_[KV]MALLOC specific param flags.

Cc: Shaohua Li <shli@xxxxxxxxxx>
Cc: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: dm-devel@xxxxxxxxxx
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
---
Hi,
this is a rebase on top of dropped "dm: clean up GFP_NIO usage" which
should be dropped as per the feedback from Mikulas.

drivers/md/dm-ioctl.c | 16 +++-------------
1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 2c7ca258c4e4..e66e5b43bc18 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -1670,19 +1670,14 @@ static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
return r;
}

-#define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */
-#define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */
-#define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
+#define DM_WIPE_BUFFER 0x0001 /* Wipe input buffer before returning from ioctl */

static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
{
if (param_flags & DM_WIPE_BUFFER)
memset(param, 0, param_size);

- if (param_flags & DM_PARAMS_KMALLOC)
- kfree(param);
- if (param_flags & DM_PARAMS_VMALLOC)
- vfree(param);
+ kvfree(param);
}

static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
@@ -1714,19 +1709,14 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kern
* Use kmalloc() rather than vmalloc() when we can.
*/
dmi = NULL;
- if (param_kernel->data_size <= KMALLOC_MAX_SIZE) {
+ if (param_kernel->data_size <= KMALLOC_MAX_SIZE)
dmi = kmalloc(param_kernel->data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
- if (dmi)
- *param_flags |= DM_PARAMS_KMALLOC;
- }

if (!dmi) {
unsigned noio_flag;
noio_flag = memalloc_noio_save();
dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_HIGH | __GFP_HIGHMEM, PAGE_KERNEL);
memalloc_noio_restore(noio_flag);
- if (dmi)
- *param_flags |= DM_PARAMS_VMALLOC;
}

if (!dmi) {
--
2.8.0.rc3