drivers/md/dm-ioctl.c: use kvmalloc rather than opencoded variant (d224e938) · Commits · 戴 / test

copy_params uses kmalloc with vmalloc fallback. We already have a helper for that - kvmalloc. This caller requires GFP_NOIO semantic so it hasn't been converted with many others by previous patches. All we need to achieve this semantic is to use the scope memalloc_noio_{save,restore} around kvmalloc. Link: http://lkml.kernel.org/r/20170306103327.2766-4-mhocko@kernel.org Signed-off-by:

Michal Hocko <mhocko@suse.com> Acked-by:

Vlastimil Babka <vbabka@suse.cz> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

drivers/md/dm-ioctl.c

+4 −9

Original line number	Diff line number	Diff line
		@@ -1691,6 +1691,7 @@ static int copy_params(struct dm_ioctl __user user, struct dm_ioctl param_kern
		struct dm_ioctl *dmi;
		int secure_data;
		const size_t minimum_data_size = offsetof(struct dm_ioctl, data);
		unsigned noio_flag;

		if (copy_from_user(param_kernel, user, minimum_data_size))
		return -EFAULT;
		@@ -1713,15 +1714,9 @@ 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)
		dmi = kmalloc(param_kernel->data_size, GFP_NOIO \| __GFP_NORETRY \| __GFP_NOMEMALLOC \| __GFP_NOWARN);

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

		if (!dmi) {
		if (secure_data && clear_user(user, param_kernel->data_size))

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