From 47a21881507f1bba1cf2fbabb0f8efce57ee7fb9 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 3 Apr 2019 17:13:11 +0100 Subject: [PATCH 04/11] file-posix: Drop s->lock_fd RH-Author: Max Reitz Message-id: <20190403171315.20841-5-mreitz@redhat.com> Patchwork-id: 85403 O-Subject: [RHEL-8.1 qemu-kvm PATCH 4/8] file-posix: Drop s->lock_fd Bugzilla: 1694148 RH-Acked-by: John Snow RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Stefano Garzarella From: Fam Zheng 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 Signed-off-by: Kevin Wolf (cherry picked from commit f2e3af29b70624659a50903bd075e1663b64c9da) Signed-off-by: Max Reitz Signed-off-by: Danilo C. L. de Paula --- 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 2a05193..97e7ff2 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; @@ -545,18 +544,6 @@ 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; @@ -811,15 +798,13 @@ 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; } @@ -830,7 +815,7 @@ 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 @@ -840,7 +825,7 @@ 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 @@ -938,9 +923,17 @@ static void raw_reopen_commit(BDRVReopenState *state) { BDRVRawReopenState *rs = state->opaque; BDRVRawState *s = state->bs->opaque; + Error *local_err = NULL; 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; @@ -1903,10 +1896,6 @@ 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; - } } /** -- 1.8.3.1