]> git.ipfire.org Git - thirdparty/linux.git/commitdiff
udmabuf: change folios array from kmalloc to kvmalloc
authorHuan Yang <link@vivo.com>
Wed, 18 Sep 2024 02:52:25 +0000 (10:52 +0800)
committerVivek Kasireddy <vivek.kasireddy@intel.com>
Fri, 20 Sep 2024 21:07:31 +0000 (14:07 -0700)
When PAGE_SIZE 4096, MAX_PAGE_ORDER 10, 64bit machine,
page_alloc only support 4MB.
If above this, trigger this warn and return NULL.

udmabuf can change size limit, if change it to 3072(3GB), and then alloc
3GB udmabuf, will fail create.

[ 4080.876581] ------------[ cut here ]------------
[ 4080.876843] WARNING: CPU: 3 PID: 2015 at mm/page_alloc.c:4556 __alloc_pages+0x2c8/0x350
[ 4080.878839] RIP: 0010:__alloc_pages+0x2c8/0x350
[ 4080.879470] Call Trace:
[ 4080.879473]  <TASK>
[ 4080.879473]  ? __alloc_pages+0x2c8/0x350
[ 4080.879475]  ? __warn.cold+0x8e/0xe8
[ 4080.880647]  ? __alloc_pages+0x2c8/0x350
[ 4080.880909]  ? report_bug+0xff/0x140
[ 4080.881175]  ? handle_bug+0x3c/0x80
[ 4080.881556]  ? exc_invalid_op+0x17/0x70
[ 4080.881559]  ? asm_exc_invalid_op+0x1a/0x20
[ 4080.882077]  ? udmabuf_create+0x131/0x400

Because MAX_PAGE_ORDER, kmalloc can max alloc 4096 * (1 << 10), 4MB
memory, each array entry is pointer(8byte), so can save 524288 pages(2GB).

Further more, costly order(order 3) may not be guaranteed that it can be
applied for, due to fragmentation.

This patch change udmabuf array use kvmalloc_array, this can fallback
alloc into vmalloc, which can guarantee allocation for any size and does
not affect the performance of kmalloc allocations.

Signed-off-by: Huan Yang <link@vivo.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240918025238.2957823-3-link@vivo.com
drivers/dma-buf/udmabuf.c

index 2170d975cc7670b44fb276a779a88fd16340c2d1..ba9dbc7caf71416fc2da0ca8cc3c589737d671a7 100644 (file)
@@ -109,7 +109,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
 
        dma_resv_assert_held(buf->resv);
 
-       pages = kmalloc_array(ubuf->pagecount, sizeof(*pages), GFP_KERNEL);
+       pages = kvmalloc_array(ubuf->pagecount, sizeof(*pages), GFP_KERNEL);
        if (!pages)
                return -ENOMEM;
 
@@ -117,7 +117,7 @@ static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map)
                pages[pg] = &ubuf->folios[pg]->page;
 
        vaddr = vm_map_ram(pages, ubuf->pagecount, -1);
-       kfree(pages);
+       kvfree(pages);
        if (!vaddr)
                return -EINVAL;
 
@@ -225,8 +225,8 @@ static void release_udmabuf(struct dma_buf *buf)
                put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
 
        unpin_all_folios(&ubuf->unpin_list);
-       kfree(ubuf->offsets);
-       kfree(ubuf->folios);
+       kvfree(ubuf->offsets);
+       kvfree(ubuf->folios);
        kfree(ubuf);
 }
 
@@ -351,14 +351,14 @@ static long udmabuf_create(struct miscdevice *device,
        if (!ubuf->pagecount)
                goto err;
 
-       ubuf->folios = kmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
-                                   GFP_KERNEL);
+       ubuf->folios = kvmalloc_array(ubuf->pagecount, sizeof(*ubuf->folios),
+                                     GFP_KERNEL);
        if (!ubuf->folios) {
                ret = -ENOMEM;
                goto err;
        }
-       ubuf->offsets = kcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
-                               GFP_KERNEL);
+       ubuf->offsets = kvcalloc(ubuf->pagecount, sizeof(*ubuf->offsets),
+                                GFP_KERNEL);
        if (!ubuf->offsets) {
                ret = -ENOMEM;
                goto err;
@@ -372,7 +372,7 @@ static long udmabuf_create(struct miscdevice *device,
                        goto err;
 
                pgcnt = list[i].size >> PAGE_SHIFT;
-               folios = kmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
+               folios = kvmalloc_array(pgcnt, sizeof(*folios), GFP_KERNEL);
                if (!folios) {
                        ret = -ENOMEM;
                        goto err;
@@ -382,7 +382,7 @@ static long udmabuf_create(struct miscdevice *device,
                ret = memfd_pin_folios(memfd, list[i].offset, end,
                                       folios, pgcnt, &pgoff);
                if (ret <= 0) {
-                       kfree(folios);
+                       kvfree(folios);
                        if (!ret)
                                ret = -EINVAL;
                        goto err;
@@ -411,7 +411,7 @@ static long udmabuf_create(struct miscdevice *device,
                        }
                }
 
-               kfree(folios);
+               kvfree(folios);
                fput(memfd);
                memfd = NULL;
        }
@@ -427,8 +427,8 @@ err:
        if (memfd)
                fput(memfd);
        unpin_all_folios(&ubuf->unpin_list);
-       kfree(ubuf->offsets);
-       kfree(ubuf->folios);
+       kvfree(ubuf->offsets);
+       kvfree(ubuf->folios);
        kfree(ubuf);
        return ret;
 }