From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49257) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gAVI5-0006ky-FI for qemu-devel@nongnu.org; Thu, 11 Oct 2018 03:21:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gAVI4-00038A-Kx for qemu-devel@nongnu.org; Thu, 11 Oct 2018 03:21:49 -0400 From: Fam Zheng Date: Thu, 11 Oct 2018 15:21:34 +0800 Message-Id: <20181011072135.588-3-famz@redhat.com> In-Reply-To: <20181011072135.588-1-famz@redhat.com> References: <20181011072135.588-1-famz@redhat.com> Subject: [Qemu-devel] [PATCH v5 2/3] file-posix: Drop s->lock_fd List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Max Reitz , qemu-block@nongnu.org The lock_fd field is not strictly necessary because transferring locked bytes from old fd to the new one shouldn't fail anyway. This spares the user one fd per image. Signed-off-by: Fam Zheng Reviewed-by: Max Reitz --- block/file-posix.c | 37 +++++++++++++------------------------ 1 file changed, 13 insertions(+), 24 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index cf5eb98caa..d493357b89 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -142,7 +142,6 @@ do { \ typedef struct BDRVRawState { int fd; - int lock_fd; bool use_lock; int type; int open_flags; @@ -153,7 +152,7 @@ typedef struct BDRVRawState { uint64_t shared_perm; /* The perms bits whose corresponding bytes are already locked in - * s->lock_fd. */ + * s->fd. */ uint64_t locked_perm; uint64_t locked_shared_perm; @@ -542,18 +541,6 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, } s->fd = fd; - s->lock_fd = -1; - if (s->use_lock) { - fd = qemu_open(filename, s->open_flags); - if (fd < 0) { - ret = -errno; - error_setg_errno(errp, errno, "Could not open '%s' for locking", - filename); - qemu_close(s->fd); - goto fail; - } - s->lock_fd = fd; - } s->perm = 0; s->shared_perm = BLK_PERM_ALL; @@ -814,15 +801,13 @@ static int raw_handle_perm_lock(BlockDriverState *bs, return 0; } - assert(s->lock_fd > 0); - switch (op) { case RAW_PL_PREPARE: - ret = raw_apply_lock_bytes(s, s->lock_fd, s->perm | new_perm, + ret = raw_apply_lock_bytes(s, s->fd, s->perm | new_perm, ~s->shared_perm | ~new_shared, false, errp); if (!ret) { - ret = raw_check_lock_bytes(s->lock_fd, new_perm, new_shared, errp); + ret = raw_check_lock_bytes(s->fd, new_perm, new_shared, errp); if (!ret) { return 0; } @@ -833,7 +818,7 @@ static int raw_handle_perm_lock(BlockDriverState *bs, op = RAW_PL_ABORT; /* fall through to unlock bytes. */ case RAW_PL_ABORT: - raw_apply_lock_bytes(s, s->lock_fd, s->perm, ~s->shared_perm, + raw_apply_lock_bytes(s, s->fd, s->perm, ~s->shared_perm, true, &local_err); if (local_err) { /* Theoretically the above call only unlocks bytes and it cannot @@ -843,7 +828,7 @@ static int raw_handle_perm_lock(BlockDriverState *bs, } break; case RAW_PL_COMMIT: - raw_apply_lock_bytes(s, s->lock_fd, new_perm, ~new_shared, + raw_apply_lock_bytes(s, s->fd, new_perm, ~new_shared, true, &local_err); if (local_err) { /* Theoretically the above call only unlocks bytes and it cannot @@ -960,10 +945,18 @@ static void raw_reopen_commit(BDRVReopenState *state) { BDRVRawReopenState *rs = state->opaque; BDRVRawState *s = state->bs->opaque; + Error *local_err = NULL; s->check_cache_dropped = rs->check_cache_dropped; s->open_flags = rs->open_flags; + /* Copy locks to the new fd before closing the old one. */ + raw_apply_lock_bytes(NULL, rs->fd, s->locked_perm, + ~s->locked_shared_perm, false, &local_err); + if (local_err) { + /* shouldn't fail in a sane host, but report it just in case. */ + error_report_err(local_err); + } qemu_close(s->fd); s->fd = rs->fd; @@ -1956,10 +1949,6 @@ static void raw_close(BlockDriverState *bs) qemu_close(s->fd); s->fd = -1; } - if (s->lock_fd >= 0) { - qemu_close(s->lock_fd); - s->lock_fd = -1; - } } /** -- 2.17.1