Commit 85c97ca7 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block: Pass BdrvChild to bdrv_aligned_preadv/pwritev and copy-on-read 



This is where we want to check the permissions, so we need to have the
BdrvChild around where they are stored.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Acked-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
parent 2807c0cd

block/io.c

+21 −16
Original line number Diff line number Diff line
@@ -925,9 +925,11 @@ bdrv_driver_pwritev_compressed(BlockDriverState *bs, uint64_t offset, 
    return drv->bdrv_co_pwritev_compressed(bs, offset, bytes, qiov);

}



static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs,

static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child,

        int64_t offset, unsigned int bytes, QEMUIOVector *qiov)

{

    BlockDriverState *bs = child->bs;



    /* Perform I/O through a temporary buffer so that users who scribble over

     * their read buffer while the operation is in progress do not end up

     * modifying the image file.  This is critical for zero-copy guest I/O
@@ -1001,10 +1003,11 @@ err: 
 * handles copy on read, zeroing after EOF, and fragmentation of large

 * reads; any other features must be implemented by the caller.

 */

static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs,

static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child,

    BdrvTrackedRequest *req, int64_t offset, unsigned int bytes,

    int64_t align, QEMUIOVector *qiov, int flags)

{

    BlockDriverState *bs = child->bs;

    int64_t total_bytes, max_bytes;

    int ret = 0;

    uint64_t bytes_remaining = bytes;
@@ -1050,7 +1053,7 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, 
        }



        if (!ret || pnum != nb_sectors) {

            ret = bdrv_co_do_copy_on_readv(bs, offset, bytes, qiov);

            ret = bdrv_co_do_copy_on_readv(child, offset, bytes, qiov);

            goto out;

        }

    }
@@ -1158,7 +1161,7 @@ int coroutine_fn bdrv_co_preadv(BdrvChild *child, 
    }



    tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_READ);

    ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align,

    ret = bdrv_aligned_preadv(child, &req, offset, bytes, align,

                              use_local_qiov ? &local_qiov : qiov,

                              flags);

    tracked_request_end(&req);
@@ -1306,10 +1309,11 @@ fail: 
 * Forwards an already correctly aligned write request to the BlockDriver,

 * after possibly fragmenting it.

 */

static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs,

static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child,

    BdrvTrackedRequest *req, int64_t offset, unsigned int bytes,

    int64_t align, QEMUIOVector *qiov, int flags)

{

    BlockDriverState *bs = child->bs;

    BlockDriver *drv = bs->drv;

    bool waited;

    int ret;
@@ -1397,12 +1401,13 @@ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, 
    return ret;

}



static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs,

static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child,

                                                int64_t offset,

                                                unsigned int bytes,

                                                BdrvRequestFlags flags,

                                                BdrvTrackedRequest *req)

{

    BlockDriverState *bs = child->bs;

    uint8_t *buf = NULL;

    QEMUIOVector local_qiov;

    struct iovec iov;
@@ -1430,7 +1435,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 
        mark_request_serialising(req, align);

        wait_serialising_requests(req);

        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD);

        ret = bdrv_aligned_preadv(bs, req, offset & ~(align - 1), align,

        ret = bdrv_aligned_preadv(child, req, offset & ~(align - 1), align,

                                  align, &local_qiov, 0);

        if (ret < 0) {

            goto fail;
@@ -1438,7 +1443,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 
        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD);



        memset(buf + head_padding_bytes, 0, zero_bytes);

        ret = bdrv_aligned_pwritev(bs, req, offset & ~(align - 1), align,

        ret = bdrv_aligned_pwritev(child, req, offset & ~(align - 1), align,

                                   align, &local_qiov,

                                   flags & ~BDRV_REQ_ZERO_WRITE);

        if (ret < 0) {
@@ -1452,7 +1457,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 
    if (bytes >= align) {

        /* Write the aligned part in the middle. */

        uint64_t aligned_bytes = bytes & ~(align - 1);

        ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, align,

        ret = bdrv_aligned_pwritev(child, req, offset, aligned_bytes, align,

                                   NULL, flags);

        if (ret < 0) {

            goto fail;
@@ -1468,7 +1473,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 
        mark_request_serialising(req, align);

        wait_serialising_requests(req);

        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL);

        ret = bdrv_aligned_preadv(bs, req, offset, align,

        ret = bdrv_aligned_preadv(child, req, offset, align,

                                  align, &local_qiov, 0);

        if (ret < 0) {

            goto fail;
@@ -1476,7 +1481,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, 
        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL);



        memset(buf, 0, bytes);

        ret = bdrv_aligned_pwritev(bs, req, offset, align, align,

        ret = bdrv_aligned_pwritev(child, req, offset, align, align,

                                   &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE);

    }

fail:
@@ -1523,7 +1528,7 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 
    tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_WRITE);



    if (!qiov) {

        ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req);

        ret = bdrv_co_do_zero_pwritev(child, offset, bytes, flags, &req);

        goto out;

    }
@@ -1542,7 +1547,7 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 
        qemu_iovec_init_external(&head_qiov, &head_iov, 1);



        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD);

        ret = bdrv_aligned_preadv(bs, &req, offset & ~(align - 1), align,

        ret = bdrv_aligned_preadv(child, &req, offset & ~(align - 1), align,

                                  align, &head_qiov, 0);

        if (ret < 0) {

            goto fail;
@@ -1584,8 +1589,8 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 
        qemu_iovec_init_external(&tail_qiov, &tail_iov, 1);



        bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL);

        ret = bdrv_aligned_preadv(bs, &req, (offset + bytes) & ~(align - 1), align,

                                  align, &tail_qiov, 0);

        ret = bdrv_aligned_preadv(child, &req, (offset + bytes) & ~(align - 1),

                                  align, align, &tail_qiov, 0);

        if (ret < 0) {

            goto fail;

        }
@@ -1603,7 +1608,7 @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 
        bytes = ROUND_UP(bytes, align);

    }



    ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, align,

    ret = bdrv_aligned_pwritev(child, &req, offset, bytes, align,

                               use_local_qiov ? &local_qiov : qiov,

                               flags);