From 4f4e0242956c209f3c6fa1e86404dac126bcdc94 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 18 Jan 2010 14:41:14 -0200 Subject: [PATCH 1/3] block: Introduce BDRV_O_NO_BACKING RH-Author: Kevin Wolf Message-id: <1263825676-3325-2-git-send-email-kwolf@redhat.com> Patchwork-id: 6440 O-Subject: [RHEL-6 KVM PATCH 1/3] block: Introduce BDRV_O_NO_BACKING Bugzilla: 556459 RH-Acked-by: Juan Quintela RH-Acked-by: Marcelo Tosatti RH-Acked-by: Eduardo Habkost Bugzilla: 556459 Upstream commit:b783e409bf17b92f4af8dc5d6bd040d0092f33e0 If an image references a backing file that doesn't exist, qemu-img info fails to open this image. Exactly in this case the info would be valuable, though: the user might want to find out which file is missing. This patch introduces a BDRV_O_NO_BACKING flag to ignore the backing file when opening the image. qemu-img info is the first user and provides info now even if the backing file is invalid. Signed-off-by: Kevin Wolf Signed-off-by: Anthony Liguori Signed-off-by: Kevin Wolf --- block.c | 4 ++-- block.h | 1 + qemu-img.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) Signed-off-by: Eduardo Habkost --- block.c | 4 ++-- block.h | 1 + qemu-img.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/block.c b/block.c index 3f3496e..20a0de2 100644 --- a/block.c +++ b/block.c @@ -477,7 +477,7 @@ int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, unlink(filename); } #endif - if (bs->backing_file[0] != '\0') { + if ((flags & BDRV_O_NO_BACKING) == 0 && bs->backing_file[0] != '\0') { /* if there is a backing file, use it */ BlockDriver *back_drv = NULL; bs->backing_hd = bdrv_new(""); @@ -1352,7 +1352,7 @@ const char *bdrv_get_encrypted_filename(BlockDriverState *bs) void bdrv_get_backing_filename(BlockDriverState *bs, char *filename, int filename_size) { - if (!bs->backing_hd) { + if (!bs->backing_file) { pstrcpy(filename, filename_size, ""); } else { pstrcpy(filename, filename_size, bs->backing_file); diff --git a/block.h b/block.h index fa51ddf..f660d5f 100644 --- a/block.h +++ b/block.h @@ -39,6 +39,7 @@ typedef struct QEMUSnapshotInfo { #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ #define BDRV_O_CACHE_WB 0x0040 /* use write-back caching */ #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ +#define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_CACHE_WB) diff --git a/qemu-img.c b/qemu-img.c index 1d97f2e..5ad88bf 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -884,7 +884,7 @@ static int img_info(int argc, char **argv) } else { drv = NULL; } - if (bdrv_open2(bs, filename, BRDV_O_FLAGS, drv) < 0) { + if (bdrv_open2(bs, filename, BRDV_O_FLAGS | BDRV_O_NO_BACKING, drv) < 0) { error("Could not open '%s'", filename); } bdrv_get_format(bs, fmt_name, sizeof(fmt_name)); -- 1.6.3.rc4.29.g8146