[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [v8 Patch 6/6]Qemu: raw posix implementation of reopen func
From: |
Supriya Kannery |
Subject: |
[Qemu-devel] [v8 Patch 6/6]Qemu: raw posix implementation of reopen functions |
Date: |
Sun, 30 Oct 2011 16:05:23 +0530 |
raw-posix driver changes for bdrv_reopen_xx functions to
safely reopen image files. Reopening of image files while
changing hostcache dynamically, is handled here.
Signed-off-by: Supriya Kannery <address@hidden>
Index: qemu/block/raw.c
===================================================================
--- qemu.orig/block/raw.c
+++ qemu/block/raw.c
@@ -9,6 +9,24 @@ static int raw_open(BlockDriverState *bs
return 0;
}
+static int raw_reopen_prepare(BlockDriverState *bs, BDRVReopenState **prs,
+ int flags)
+{
+ return bdrv_reopen_prepare(bs->file, prs, flags);
+}
+
+static void raw_reopen_commit(BlockDriverState *bs, BDRVReopenState *rs,
+ int flags)
+{
+ bdrv_reopen_commit(bs->file, rs, flags);
+ bs->open_flags = bs->file->open_flags;
+}
+
+static void raw_reopen_abort(BlockDriverState *bs, BDRVReopenState *rs)
+{
+ bdrv_reopen_abort(bs->file, rs);
+}
+
static int coroutine_fn raw_co_readv(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, QEMUIOVector *qiov)
{
@@ -107,7 +125,10 @@ static BlockDriver bdrv_raw = {
/* It's really 0, but we need to make g_malloc() happy */
.instance_size = 1,
-
+ .bdrv_reopen_prepare
+ = raw_reopen_prepare,
+ .bdrv_reopen_commit = raw_reopen_commit,
+ .bdrv_reopen_abort = raw_reopen_abort,
.bdrv_open = raw_open,
.bdrv_close = raw_close,
Index: qemu/block/raw-posix.c
===================================================================
--- qemu.orig/block/raw-posix.c
+++ qemu/block/raw-posix.c
@@ -279,6 +279,60 @@ static int raw_open(BlockDriverState *bs
return raw_open_common(bs, filename, flags, 0);
}
+static int raw_reopen_prepare(BlockDriverState *bs, BDRVReopenState **prs,
+ int flags)
+{
+ BDRVReopenState *raw_rs = g_malloc0(sizeof(BDRVReopenState));
+ BDRVRawState *s = bs->opaque;
+
+ raw_rs->bs = bs;
+ raw_rs->reopen_flags = s->open_flags;
+ raw_rs->reopen_fd = -1;
+ *prs = raw_rs;
+ int ret = 0;
+
+ /* If only O_DIRECT to be toggled, use fcntl */
+ if (!((bs->open_flags & ~BDRV_O_NOCACHE) ^
+ (flags & ~BDRV_O_NOCACHE))) {
+ raw_rs->reopen_fd = dup(s->fd);
+ if (raw_rs->reopen_fd <= 0) {
+ return -1;
+ }
+ if ((flags & BDRV_O_NOCACHE)) {
+ raw_rs->reopen_flags |= O_DIRECT;
+ } else {
+ raw_rs->reopen_flags &= ~O_DIRECT;
+ }
+ ret = fcntl_setfl(raw_rs->reopen_fd, raw_rs->reopen_flags);
+ }
+
+ /* TBD: Handle O_DSYNC and other flags */
+
+ return ret;
+}
+
+static void raw_reopen_commit(BlockDriverState *bs, BDRVReopenState *rs,
+ int flags)
+{
+ BDRVRawState *s = bs->opaque;
+
+ /* Set new flags, so replace old fd with new one */
+ close(s->fd);
+ s->fd = rs->reopen_fd;
+ s->open_flags = rs->reopen_flags;
+ bs->open_flags = flags;
+ g_free(rs);
+
+}
+
+static void raw_reopen_abort(BlockDriverState *bs, BDRVReopenState *rs)
+{
+ if (rs->reopen_fd != -1) {
+ close(rs->reopen_fd);
+ }
+ g_free(rs);
+}
+
/* XXX: use host sector size if necessary with:
#ifdef DIOCGSECTORSIZE
{
@@ -631,6 +685,9 @@ static BlockDriver bdrv_file = {
.instance_size = sizeof(BDRVRawState),
.bdrv_probe = NULL, /* no probe for protocols */
.bdrv_file_open = raw_open,
+ .bdrv_reopen_prepare = raw_reopen_prepare,
+ .bdrv_reopen_commit = raw_reopen_commit,
+ .bdrv_reopen_abort = raw_reopen_abort,
.bdrv_close = raw_close,
.bdrv_create = raw_create,
.bdrv_co_discard = raw_co_discard,
- [Qemu-devel] [v8 Patch 0/6]Qemu: Host pagecache setting from cmdline and monitor, Supriya Kannery, 2011/10/30
- [Qemu-devel] [v8 Patch 1/6]Qemu: Enhance "info block" to display host cache setting, Supriya Kannery, 2011/10/30
- [Qemu-devel] [v8 Patch 2/6]Qemu: Error classes for file reopen and data sync failure, Supriya Kannery, 2011/10/30
- [Qemu-devel] [v8 Patch 4/6]Qemu: Add commandline -drive option 'hostcache', Supriya Kannery, 2011/10/30
- [Qemu-devel] [v8 Patch 3/6]Qemu: Cmd "block_set_hostcache" for dynamic cache change, Supriya Kannery, 2011/10/30
- [Qemu-devel] [v8 Patch 6/6]Qemu: raw posix implementation of reopen functions,
Supriya Kannery <=
- [Qemu-devel] [v8 Patch 5/6]Qemu: Framework for reopening images safely, Supriya Kannery, 2011/10/30