In the past, the function __vmalloc didn't respect the GFP flags - it
allocated memory with the provided gfp flags, but it allocated page tables
with GFP_KERNEL. This was fixed in commit
451769ebb7e7 ("mm/vmalloc:
alloc GFP_NO{FS,IO} for vmalloc") so the memalloc_noio_{save,restore}
workaround is no longer needed.
The function kvmalloc didn't like flags different from GFP_KERNEL. This
was fixed in commit
a421ef303008 ("mm: allow !GFP_KERNEL allocations
for kvmalloc"), so kvmalloc can now be called with GFP_NOIO.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
*data_mode = DATA_MODE_VMALLOC;
- /*
- * __vmalloc allocates the data pages and auxiliary structures with
- * gfp_flags that were specified, but pagetables are always allocated
- * with GFP_KERNEL, no matter what was specified as gfp_mask.
- *
- * Consequently, we must set per-process flag PF_MEMALLOC_NOIO so that
- * all allocations done by this process (including pagetables) are done
- * as if GFP_NOIO was specified.
- */
- if (gfp_mask & __GFP_NORETRY) {
- unsigned int noio_flag = memalloc_noio_save();
- void *ptr = __vmalloc(c->block_size, gfp_mask);
-
- memalloc_noio_restore(noio_flag);
- return ptr;
- }
-
return __vmalloc(c->block_size, gfp_mask);
}
struct dm_ioctl *dmi;
int secure_data;
const size_t minimum_data_size = offsetof(struct dm_ioctl, data);
- unsigned int noio_flag;
/* check_version() already copied version from userspace, avoid TOCTOU */
if (copy_from_user((char *)param_kernel + sizeof(param_kernel->version),
* Use kmalloc() rather than vmalloc() when we can.
*/
dmi = NULL;
- noio_flag = memalloc_noio_save();
- dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL | __GFP_HIGH);
- memalloc_noio_restore(noio_flag);
+ dmi = kvmalloc(param_kernel->data_size, GFP_NOIO | __GFP_HIGH);
if (!dmi) {
if (secure_data && clear_user(user, param_kernel->data_size))