diff options
| author | Huan Yang <link@vivo.com> | 2025-04-28 15:38:29 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-09-19 16:35:42 +0200 |
| commit | 3a7fd0e56eaa05fa4179c5ea577fc67504d1875b (patch) | |
| tree | 666a36d03047f9ddad51b86eb097c3f7560bad9d | |
| parent | 87bbcb73d603641aaee9b153fe033f6abe2d0f41 (diff) | |
Revert "udmabuf: fix vmap_udmabuf error page set"
[ Upstream commit ceb7b62eaaaacfcf87473bd2e99ac73a758620cb ]
This reverts commit 18d7de823b7150344d242c3677e65d68c5271b04.
We cannot use vmap_pfn() in vmap_udmabuf() as it would fail the pfn_valid()
check in vmap_pfn_apply(). This is because vmap_pfn() is intended to be
used for mapping non-struct-page memory such as PCIe BARs. Since, udmabuf
mostly works with pages/folios backed by shmem/hugetlbfs/THP, vmap_pfn()
is not the right tool or API to invoke for implementing vmap.
Signed-off-by: Huan Yang <link@vivo.com>
Suggested-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Reported-by: Bingbu Cao <bingbu.cao@linux.intel.com>
Closes: https://lore.kernel.org/dri-devel/eb7e0137-3508-4287-98c4-816c5fd98e10@vivo.com/T/#mbda4f64a3532b32e061f4e8763bc8e307bea3ca8
Acked-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Link: https://lore.kernel.org/r/20250428073831.19942-2-link@vivo.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/dma-buf/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/dma-buf/udmabuf.c | 22 |
2 files changed, 7 insertions, 16 deletions
diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig index fee04fdb0822..b46eb8a552d7 100644 --- a/drivers/dma-buf/Kconfig +++ b/drivers/dma-buf/Kconfig @@ -36,7 +36,6 @@ config UDMABUF depends on DMA_SHARED_BUFFER depends on MEMFD_CREATE || COMPILE_TEST depends on MMU - select VMAP_PFN help A driver to let userspace turn memfd regions into dma-bufs. Qemu can use this to create host dmabufs for guest framebuffers. diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index 959f690b1226..0e127a9109e7 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -74,29 +74,21 @@ static int mmap_udmabuf(struct dma_buf *buf, struct vm_area_struct *vma) static int vmap_udmabuf(struct dma_buf *buf, struct iosys_map *map) { struct udmabuf *ubuf = buf->priv; - unsigned long *pfns; + struct page **pages; void *vaddr; pgoff_t pg; dma_resv_assert_held(buf->resv); - /** - * HVO may free tail pages, so just use pfn to map each folio - * into vmalloc area. - */ - pfns = kvmalloc_array(ubuf->pagecount, sizeof(*pfns), GFP_KERNEL); - if (!pfns) + pages = kvmalloc_array(ubuf->pagecount, sizeof(*pages), GFP_KERNEL); + if (!pages) return -ENOMEM; - for (pg = 0; pg < ubuf->pagecount; pg++) { - unsigned long pfn = folio_pfn(ubuf->folios[pg]); - - pfn += ubuf->offsets[pg] >> PAGE_SHIFT; - pfns[pg] = pfn; - } + for (pg = 0; pg < ubuf->pagecount; pg++) + pages[pg] = &ubuf->folios[pg]->page; - vaddr = vmap_pfn(pfns, ubuf->pagecount, PAGE_KERNEL); - kvfree(pfns); + vaddr = vm_map_ram(pages, ubuf->pagecount, -1); + kvfree(pages); if (!vaddr) return -EINVAL; |