From 9b3702c45245f7bbb51350c25e8cf304c490b96a Mon Sep 17 00:00:00 2001

From: Paolo Bonzini <pbonzini@redhat.com>

Date: Thu, 7 Nov 2013 07:19:42 +0100

Subject: [PATCH 05/81] block: make bdrv_co_is_allocated static

RH-Author: Paolo Bonzini <pbonzini@redhat.com>

Message-id: <1382084091-16636-6-git-send-email-pbonzini@redhat.com>

Patchwork-id: 54988

O-Subject: [RHEL 7.0 qemu-kvm PATCH 05/26] block: make bdrv_co_is_allocated static

Bugzilla: 989646

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

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

RH-Acked-by: Kevin Wolf <kwolf@redhat.com>

bdrv_is_allocated can detect coroutine context and go through a fast

path, similar to other block layer functions.

Reviewed-by: Eric Blake <eblake@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

(cherry picked from commit bdad13b9deec47d5d9eaf7f43867d19a79471244)

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

---

 block.c               |   24 +++++++++++++++---------

 block/raw.c           |    2 +-

 block/stream.c        |    4 ++--

 include/block/block.h |    2 --

 4 files changed, 18 insertions(+), 14 deletions(-)

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

index d5aeff7..0607cc6 100644

--- a/block.c

+++ b/block.c

@@ -2555,7 +2555,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,

     if (flags & BDRV_REQ_COPY_ON_READ) {

         int pnum;

-        ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum);

+        ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum);

         if (ret < 0) {

             goto out;

         }

@@ -3027,8 +3027,9 @@ typedef struct BdrvCoIsAllocatedData {

  * 'nb_sectors' is the max value 'pnum' should be set to.  If nb_sectors goes

  * beyond the end of the disk image it will be clamped.

  */

-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,

-                                      int nb_sectors, int *pnum)

+static int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs,

+                                             int64_t sector_num,

+                                             int nb_sectors, int *pnum)

 {

     int64_t n;

@@ -3078,10 +3079,15 @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,

         .done = false,

     };

-    co = qemu_coroutine_create(bdrv_is_allocated_co_entry);

-    qemu_coroutine_enter(co, &data);

-    while (!data.done) {

-        qemu_aio_wait();

+    if (qemu_in_coroutine()) {

+        /* Fast-path if already in coroutine context */

+        bdrv_is_allocated_co_entry(&data);

+    } else {

+        co = qemu_coroutine_create(bdrv_is_allocated_co_entry);

+        qemu_coroutine_enter(co, &data);

+        while (!data.done) {

+            qemu_aio_wait();

+        }

     }

     return data.ret;

 }

@@ -3109,8 +3115,8 @@ int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,

     intermediate = top;

     while (intermediate && intermediate != base) {

         int pnum_inter;

-        ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors,

-                                   &pnum_inter);

+        ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors,

+                                &pnum_inter);

         if (ret < 0) {

             return ret;

         } else if (ret) {

diff --git a/block/raw.c b/block/raw.c

index 8c81de9..f78ff39 100644

--- a/block/raw.c

+++ b/block/raw.c

@@ -39,7 +39,7 @@ static int coroutine_fn raw_co_is_allocated(BlockDriverState *bs,

                                             int64_t sector_num,

                                             int nb_sectors, int *pnum)

 {

-    return bdrv_co_is_allocated(bs->file, sector_num, nb_sectors, pnum);

+    return bdrv_is_allocated(bs->file, sector_num, nb_sectors, pnum);

 }

 static int coroutine_fn raw_co_write_zeroes(BlockDriverState *bs,

diff --git a/block/stream.c b/block/stream.c

index d6df06f..f8efa8a 100644

--- a/block/stream.c

+++ b/block/stream.c

@@ -115,8 +115,8 @@ wait:

             break;

         }

-        ret = bdrv_co_is_allocated(bs, sector_num,

-                                   STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);

+        ret = bdrv_is_allocated(bs, sector_num,

+                                STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n);

         if (ret == 1) {

             /* Allocated in the top, no need to copy.  */

             copy = false;

diff --git a/include/block/block.h b/include/block/block.h

index 1a3ed22..1932e67 100644

--- a/include/block/block.h

+++ b/include/block/block.h

@@ -192,8 +192,6 @@ int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,

  */

 int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,

     int nb_sectors);

-int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,

-    int nb_sectors, int *pnum);

 int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,

                                             BlockDriverState *base,

                                             int64_t sector_num,

-- 

1.7.1