From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:45602) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1wj7-0008Ms-SN for qemu-devel@nongnu.org; Thu, 16 Aug 2012 05:50:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1T1wj6-0006rT-Iw for qemu-devel@nongnu.org; Thu, 16 Aug 2012 05:50:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47888) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1T1wj6-0006pX-B8 for qemu-devel@nongnu.org; Thu, 16 Aug 2012 05:50:52 -0400 From: Kevin Wolf Date: Thu, 16 Aug 2012 11:50:46 +0200 Message-Id: <1345110646-12487-1-git-send-email-kwolf@redhat.com> In-Reply-To: References: Subject: [Qemu-devel] [PATCH v2 2/2] vmdk: Read footer for streamOptimized images List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, stefanha@gmail.com, jcody@redhat.com The footer takes precedence over the header when it exists. It contains the real grain directory offset that is missing in the header. Without this patch, streamOptimized images with a footer cannot be read. Signed-off-by: Kevin Wolf --- v2: - Enough footer sanity checks, I hope? :-) block/vmdk.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 56 insertions(+), 0 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 9648398..bba4c61 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -35,6 +35,7 @@ #define VMDK4_FLAG_RGD (1 << 1) #define VMDK4_FLAG_COMPRESS (1 << 16) #define VMDK4_FLAG_MARKER (1 << 17) +#define VMDK4_GD_AT_END 0xffffffffffffffffULL typedef struct { uint32_t version; @@ -115,6 +116,13 @@ typedef struct VmdkGrainMarker { uint8_t data[0]; } VmdkGrainMarker; +enum { + MARKER_END_OF_STREAM = 0, + MARKER_GRAIN_TABLE = 1, + MARKER_GRAIN_DIRECTORY = 2, + MARKER_FOOTER = 3, +}; + static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename) { uint32_t magic; @@ -451,6 +459,54 @@ static int vmdk_open_vmdk4(BlockDriverState *bs, if (header.capacity == 0 && header.desc_offset) { return vmdk_open_desc_file(bs, flags, header.desc_offset << 9); } + + if (le64_to_cpu(header.gd_offset) == VMDK4_GD_AT_END) { + /* + * The footer takes precedence over the header, so read it in. The + * footer starts at offset -1024 from the end: One sector for the + * footer, and another one for the end-of-stream marker. + */ + struct { + struct { + uint64_t val; + uint32_t size; + uint32_t type; + uint8_t pad[512 - 16]; + } QEMU_PACKED footer_marker; + + uint32_t magic; + VMDK4Header header; + uint8_t pad[512 - 4 - sizeof(VMDK4Header)]; + + struct { + uint64_t val; + uint32_t size; + uint32_t type; + uint8_t pad[512 - 16]; + } QEMU_PACKED eos_marker; + } QEMU_PACKED footer; + + ret = bdrv_pread(file, + bs->file->total_sectors * 512 - 1536, + &footer, sizeof(footer)); + if (ret < 0) { + return ret; + } + + /* Some sanity checks for the footer */ + if (be32_to_cpu(footer.magic) != VMDK4_MAGIC || + le32_to_cpu(footer.footer_marker.size) != 0 || + le32_to_cpu(footer.footer_marker.type) != MARKER_FOOTER || + le64_to_cpu(footer.eos_marker.val) != 0 || + le32_to_cpu(footer.eos_marker.size) != 0 || + le32_to_cpu(footer.eos_marker.type) != MARKER_END_OF_STREAM) + { + return -EINVAL; + } + + header = footer.header; + } + l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte) * le64_to_cpu(header.granularity); if (l1_entry_sectors == 0) { -- 1.7.6.5