diff options
| -rw-r--r-- | drivers/md/dm-bufio.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index c6083132c4b8..0387e05cdb98 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -319,6 +319,9 @@ static void __cache_size_refresh(void) static void *alloc_buffer_data(struct dm_bufio_client *c, gfp_t gfp_mask, enum data_mode *data_mode) { + unsigned noio_flag; + void *ptr; + if (c->block_size <= DM_BUFIO_BLOCK_SIZE_SLAB_LIMIT) { *data_mode = DATA_MODE_SLAB; return kmem_cache_alloc(DM_BUFIO_CACHE(c), gfp_mask); @@ -332,7 +335,26 @@ static void *alloc_buffer_data(struct dm_bufio_client *c, gfp_t gfp_mask, } *data_mode = DATA_MODE_VMALLOC; - return __vmalloc(c->block_size, gfp_mask, PAGE_KERNEL); + + /* + * __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) + noio_flag = memalloc_noio_save(); + + ptr = __vmalloc(c->block_size, gfp_mask, PAGE_KERNEL); + + if (gfp_mask & __GFP_NORETRY) + memalloc_noio_restore(noio_flag); + + return ptr; } /* |