From 4667112e87999632688621951ce8c2ec8a0ebb8d Mon Sep 17 00:00:00 2001

From: Max Reitz <mreitz@redhat.com>

Date: Mon, 18 Jun 2018 14:53:35 +0200

Subject: [PATCH 06/57] block/file-posix: Pass FD to locking helpers

RH-Author: Max Reitz <mreitz@redhat.com>

Message-id: <20180618145337.633-2-mreitz@redhat.com>

Patchwork-id: 80751

O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH 1/3] block/file-posix: Pass FD to locking helpers

Bugzilla: 1519144

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>

raw_apply_lock_bytes() and raw_check_lock_bytes() currently take a

BDRVRawState *, but they only use the lock_fd field.  During image

creation, we do not have a BDRVRawState, but we do have an FD; so if we

want to reuse the functions there, we should modify them to receive only

the FD.

Signed-off-by: Max Reitz <mreitz@redhat.com>

Reviewed-by: Fam Zheng <famz@redhat.com>

Message-id: 20180509215336.31304-2-mreitz@redhat.com

Signed-off-by: Max Reitz <mreitz@redhat.com>

(cherry picked from commit d0a96155de099d388f5e1f46277a54bdcfbb0bb2)

Signed-off-by: Max Reitz <mreitz@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block/file-posix.c | 27 ++++++++++++++-------------

 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/block/file-posix.c b/block/file-posix.c

index 3794c00..c98a4a1 100644

--- a/block/file-posix.c

+++ b/block/file-posix.c

@@ -630,7 +630,7 @@ typedef enum {

  * file; if @unlock == true, also unlock the unneeded bytes.

  * @shared_perm_lock_bits is the mask of all permissions that are NOT shared.

  */

-static int raw_apply_lock_bytes(BDRVRawState *s,

+static int raw_apply_lock_bytes(int fd,

                                 uint64_t perm_lock_bits,

                                 uint64_t shared_perm_lock_bits,

                                 bool unlock, Error **errp)

@@ -641,13 +641,13 @@ static int raw_apply_lock_bytes(BDRVRawState *s,

     PERM_FOREACH(i) {

         int off = RAW_LOCK_PERM_BASE + i;

         if (perm_lock_bits & (1ULL << i)) {

-            ret = qemu_lock_fd(s->lock_fd, off, 1, false);

+            ret = qemu_lock_fd(fd, off, 1, false);

             if (ret) {

                 error_setg(errp, "Failed to lock byte %d", off);

                 return ret;

             }

         } else if (unlock) {

-            ret = qemu_unlock_fd(s->lock_fd, off, 1);

+            ret = qemu_unlock_fd(fd, off, 1);

             if (ret) {

                 error_setg(errp, "Failed to unlock byte %d", off);

                 return ret;

@@ -657,13 +657,13 @@ static int raw_apply_lock_bytes(BDRVRawState *s,

     PERM_FOREACH(i) {

         int off = RAW_LOCK_SHARED_BASE + i;

         if (shared_perm_lock_bits & (1ULL << i)) {

-            ret = qemu_lock_fd(s->lock_fd, off, 1, false);

+            ret = qemu_lock_fd(fd, off, 1, false);

             if (ret) {

                 error_setg(errp, "Failed to lock byte %d", off);

                 return ret;

             }

         } else if (unlock) {

-            ret = qemu_unlock_fd(s->lock_fd, off, 1);

+            ret = qemu_unlock_fd(fd, off, 1);

             if (ret) {

                 error_setg(errp, "Failed to unlock byte %d", off);

                 return ret;

@@ -674,8 +674,7 @@ static int raw_apply_lock_bytes(BDRVRawState *s,

 }

 /* Check "unshared" bytes implied by @perm and ~@shared_perm in the file. */

-static int raw_check_lock_bytes(BDRVRawState *s,

-                                uint64_t perm, uint64_t shared_perm,

+static int raw_check_lock_bytes(int fd, uint64_t perm, uint64_t shared_perm,

                                 Error **errp)

 {

     int ret;

@@ -685,7 +684,7 @@ static int raw_check_lock_bytes(BDRVRawState *s,

         int off = RAW_LOCK_SHARED_BASE + i;

         uint64_t p = 1ULL << i;

         if (perm & p) {

-            ret = qemu_lock_fd_test(s->lock_fd, off, 1, true);

+            ret = qemu_lock_fd_test(fd, off, 1, true);

             if (ret) {

                 char *perm_name = bdrv_perm_names(p);

                 error_setg(errp,

@@ -702,7 +701,7 @@ static int raw_check_lock_bytes(BDRVRawState *s,

         int off = RAW_LOCK_PERM_BASE + i;

         uint64_t p = 1ULL << i;

         if (!(shared_perm & p)) {

-            ret = qemu_lock_fd_test(s->lock_fd, off, 1, true);

+            ret = qemu_lock_fd_test(fd, off, 1, true);

             if (ret) {

                 char *perm_name = bdrv_perm_names(p);

                 error_setg(errp,

@@ -739,11 +738,11 @@ static int raw_handle_perm_lock(BlockDriverState *bs,

     switch (op) {

     case RAW_PL_PREPARE:

-        ret = raw_apply_lock_bytes(s, s->perm | new_perm,

+        ret = raw_apply_lock_bytes(s->lock_fd, s->perm | new_perm,

                                    ~s->shared_perm | ~new_shared,

                                    false, errp);

         if (!ret) {

-            ret = raw_check_lock_bytes(s, new_perm, new_shared, errp);

+            ret = raw_check_lock_bytes(s->lock_fd, new_perm, new_shared, errp);

             if (!ret) {

                 return 0;

             }

@@ -751,7 +750,8 @@ 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->perm, ~s->shared_perm, true, &local_err);

+        raw_apply_lock_bytes(s->lock_fd, s->perm, ~s->shared_perm,

+                             true, &local_err);

         if (local_err) {

             /* Theoretically the above call only unlocks bytes and it cannot

              * fail. Something weird happened, report it.

@@ -760,7 +760,8 @@ static int raw_handle_perm_lock(BlockDriverState *bs,

         }

         break;

     case RAW_PL_COMMIT:

-        raw_apply_lock_bytes(s, new_perm, ~new_shared, true, &local_err);

+        raw_apply_lock_bytes(s->lock_fd, new_perm, ~new_shared,

+                             true, &local_err);

         if (local_err) {

             /* Theoretically the above call only unlocks bytes and it cannot

              * fail. Something weird happened, report it.

-- 

1.8.3.1