From 62ace01c29691d4d9d40a84d2e36eae4defc1f80 Mon Sep 17 00:00:00 2001 Message-Id: <62ace01c29691d4d9d40a84d2e36eae4defc1f80.1350493760.git.minovotn@redhat.com> In-Reply-To: References: From: Jeffrey Cody Date: Wed, 17 Oct 2012 05:59:24 +0200 Subject: [PATCH 11/35] block: correctly set the keep_read_only flag RH-Author: Jeffrey Cody Message-id: Patchwork-id: 43268 O-Subject: [RHEL6.4 qemu-kvm PATCH v4 11/35] block: correctly set the keep_read_only flag Bugzilla: 767233 RH-Acked-by: Paolo Bonzini RH-Acked-by: Eric Blake RH-Acked-by: Kevin Wolf I believe the bs->keep_read_only flag is supposed to reflect the initial open state of the device. If the device is initially opened R/O, then commit operations, or reopen operations changing to R/W, are prohibited. Currently, the keep_read_only flag is only accurate for the active layer, and its backing file. Subsequent images end up always having the keep_read_only flag set. For instance, what happens now: [ base ] kro = 1, ro = 1 | v [ snap-1 ] kro = 1, ro = 1 | v [ snap-2 ] kro = 0, ro = 1 | v [ active ] kro = 0, ro = 0 What we want: [ base ] kro = 0, ro = 1 | v [ snap-1 ] kro = 0, ro = 1 | v [ snap-2 ] kro = 0, ro = 1 | v [ active ] kro = 0, ro = 0 Signed-off-by: Jeff Cody Signed-off-by: Kevin Wolf (cherry picked from commit be028adcedd68ca4d78fdc43e7e2fa4f1cdbc653) Conflicts: block.c block.h --- block.c | 15 ++++++++------- block.h | 1 + 2 files changed, 9 insertions(+), 7 deletions(-) Signed-off-by: Michal Novotny --- block.c | 15 ++++++++------- block.h | 1 + 2 files changed, 9 insertions(+), 7 deletions(-) diff --git a/block.c b/block.c index 1f255c1..e0edad5 100644 --- a/block.c +++ b/block.c @@ -507,6 +507,8 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename, open_flags |= BDRV_O_RDWR; } + bs->read_only = !(open_flags & BDRV_O_RDWR); + /* Open the image, either directly or using a protocol */ if (drv->bdrv_file_open) { ret = drv->bdrv_file_open(bs, filename, open_flags); @@ -521,7 +523,6 @@ static int bdrv_open_common(BlockDriverState *bs, const char *filename, goto free_and_fail; } - bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR); ret = refresh_total_sectors(bs, bs->total_sectors); if (ret < 0) { @@ -646,6 +647,12 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, goto unlink_and_fail; } + if (flags & BDRV_O_RDWR) { + flags |= BDRV_O_ALLOW_RDWR; + } + + bs->keep_read_only = !(flags & BDRV_O_ALLOW_RDWR); + /* Open the image */ ret = bdrv_open_common(bs, filename, flags, drv); if (ret < 0) { @@ -681,12 +688,6 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags, bdrv_close(bs); return ret; } - if (bs->is_temporary) { - bs->backing_hd->keep_read_only = !(flags & BDRV_O_RDWR); - } else { - /* base image inherits from "parent" */ - bs->backing_hd->keep_read_only = bs->keep_read_only; - } } if (!bdrv_key_required(bs)) { diff --git a/block.h b/block.h index 52155bc..8e4485c 100644 --- a/block.h +++ b/block.h @@ -71,6 +71,7 @@ typedef struct BlockDevOps { #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ #define BDRV_O_INCOMING 0x0800 /* consistency hint for incoming migration */ +#define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_CACHE_WB) -- 1.7.11.7