From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:58780) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RODf0-0007mS-Je for qemu-devel@nongnu.org; Wed, 09 Nov 2011 14:18:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RODey-00044R-S9 for qemu-devel@nongnu.org; Wed, 09 Nov 2011 14:18:10 -0500 Received: from mx1.redhat.com ([209.132.183.28]:52485) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RODey-00044C-E1 for qemu-devel@nongnu.org; Wed, 09 Nov 2011 14:18:08 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id pA9JI732002949 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 9 Nov 2011 14:18:07 -0500 From: Juan Quintela Date: Wed, 9 Nov 2011 20:16:43 +0100 Message-Id: <8920a92ef9be3313494009853d25bae9cc5a1c54.1320865627.git.quintela@redhat.com> In-Reply-To: References: In-Reply-To: References: Subject: [Qemu-devel] [PATCH 2/2] drive_open: Add invalidate option for block devices List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Linux allows to invalidate block devices. This is needed for the incoming migration part. Signed-off-by: Juan Quintela --- block.h | 2 ++ block/raw-posix.c | 24 ++++++++++++++++++++++++ blockdev.c | 8 ++++---- 3 files changed, 30 insertions(+), 4 deletions(-) diff --git a/block.h b/block.h index 38cd748..517b446 100644 --- a/block.h +++ b/block.h @@ -61,6 +61,8 @@ typedef struct BlockDevOps { #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_NO_FLUSH 0x0200 /* disable flushing on this disk */ +#define BDRV_O_INVALIDATE 0x0400 /* invalidate buffer cache for this device. + re-read things from server */ #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH) diff --git a/block/raw-posix.c b/block/raw-posix.c index a3de373..84303a0 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -52,6 +52,7 @@ #include #include #include +#include #endif #if defined (__FreeBSD__) || defined(__FreeBSD_kernel__) #include @@ -218,6 +219,29 @@ static int raw_open_common(BlockDriverState *bs, const char *filename, s->fd = fd; s->aligned_buf = NULL; +#ifdef __linux__ + if ((bdrv_flags & BDRV_O_INVALIDATE)) { + struct stat buf; + int res; + + res = fstat(fd, &buf); + + if (res < 0) { + return -errno; + } + + if (S_ISBLK(buf.st_mode)) { + printf("we are in a block device: %s\n", filename); + res = ioctl(fd, BLKFLSBUF, 0); + if (res < 0) { + fprintf(stderr, "qemu: buffer invalidation of %s" + " failed with error %d\n", filename, errno); + return -errno; + } + } + } +#endif /* __linux__ */ + if ((bdrv_flags & BDRV_O_NOCACHE)) { /* * Allocate a buffer for read/modify/write cycles. Chose the size diff --git a/blockdev.c b/blockdev.c index a10de7a..ea02ee7 100644 --- a/blockdev.c +++ b/blockdev.c @@ -217,10 +217,10 @@ static int parse_block_error_action(const char *buf, int is_read) } } -static int drive_open(DriveInfo *dinfo) +static int drive_open(DriveInfo *dinfo, int extra_flags) { int res = bdrv_open(dinfo->bdrv, dinfo->file, - dinfo->bdrv_flags, dinfo->drv); + dinfo->bdrv_flags | extra_flags, dinfo->drv); if (res < 0) { fprintf(stderr, "qemu: could not open disk image %s: %s\n", @@ -237,7 +237,7 @@ int drives_reinit(void) if (dinfo->opened && !bdrv_is_read_only(dinfo->bdrv)) { int res; bdrv_close(dinfo->bdrv); - res = drive_open(dinfo); + res = drive_open(dinfo, BDRV_O_INVALIDATE); if (res) { fprintf(stderr, "qemu: re-open of %s failed with error %d\n", dinfo->file, res); @@ -550,7 +550,7 @@ DriveInfo *drive_init(QemuOpts *opts, int default_to_scsi) dinfo->drv = drv; dinfo->opened = 1; - if (drive_open(dinfo) < 0) { + if (drive_open(dinfo, 0) < 0) { goto err; } -- 1.7.7