Commit 75af1f34 authored by Peter Lieven's avatar Peter Lieven Committed by Kevin Wolf
Browse files

block: introduce BDRV_REQUEST_MAX_SECTORS 



we check and adjust request sizes at several places with
sometimes inconsistent checks or default values:
 INT_MAX
 INT_MAX >> BDRV_SECTOR_BITS
 UINT_MAX >> BDRV_SECTOR_BITS
 SIZE_MAX >> BDRV_SECTOR_BITS

This patches introdocues a macro for the maximal allowed sectors
per request and uses it at several places.

Signed-off-by: default avatarPeter Lieven <pl@kamp.de>
Reviewed-by: default avatarDenis V. Lunev <den@openvz.org>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 1ce52846

block.c

+9 −12
Original line number Diff line number Diff line
@@ -2647,7 +2647,7 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 
{

    int64_t len;



    if (size > INT_MAX) {

    if (size > BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) {

        return -EIO;

    }
@@ -2671,7 +2671,7 @@ static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, 
static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,

                              int nb_sectors)

{

    if (nb_sectors < 0 || nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {

    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {

        return -EIO;

    }
@@ -2758,7 +2758,7 @@ static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, 
        .iov_len = nb_sectors * BDRV_SECTOR_SIZE,

    };



    if (nb_sectors < 0 || nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {

    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {

        return -EINVAL;

    }
@@ -2826,13 +2826,10 @@ int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags) 
    }



    for (;;) {

        nb_sectors = target_sectors - sector_num;

        nb_sectors = MIN(target_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS);

        if (nb_sectors <= 0) {

            return 0;

        }

        if (nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {

            nb_sectors = INT_MAX / BDRV_SECTOR_SIZE;

        }

        ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n);

        if (ret < 0) {

            error_report("error getting block status at sector %" PRId64 ": %s",
@@ -3167,7 +3164,7 @@ static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, 
    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,

    BdrvRequestFlags flags)

{

    if (nb_sectors < 0 || nb_sectors > (UINT_MAX >> BDRV_SECTOR_BITS)) {

    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {

        return -EINVAL;

    }
@@ -3202,8 +3199,8 @@ static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, 
    struct iovec iov = {0};

    int ret = 0;



    int max_write_zeroes = bs->bl.max_write_zeroes ?

                           bs->bl.max_write_zeroes : INT_MAX;

    int max_write_zeroes = MIN_NON_ZERO(bs->bl.max_write_zeroes,

                                        BDRV_REQUEST_MAX_SECTORS);



    while (nb_sectors > 0 && !ret) {

        int num = nb_sectors;
@@ -3458,7 +3455,7 @@ static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, 
    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,

    BdrvRequestFlags flags)

{

    if (nb_sectors < 0 || nb_sectors > (INT_MAX >> BDRV_SECTOR_BITS)) {

    if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) {

        return -EINVAL;

    }
@@ -5120,7 +5117,7 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, 
        return 0;

    }



    max_discard = bs->bl.max_discard ?  bs->bl.max_discard : INT_MAX;

    max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS);

    while (nb_sectors > 0) {

        int ret;

        int num = nb_sectors;

hw/block/virtio-blk.c

+2 −2
Original line number Diff line number Diff line
@@ -381,7 +381,7 @@ void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb) 
    }



    max_xfer_len = blk_get_max_transfer_length(mrb->reqs[0]->dev->blk);

    max_xfer_len = MIN_NON_ZERO(max_xfer_len, INT_MAX);

    max_xfer_len = MIN_NON_ZERO(max_xfer_len, BDRV_REQUEST_MAX_SECTORS);



    qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),

          &multireq_compare);
@@ -447,7 +447,7 @@ static bool virtio_blk_sect_range_ok(VirtIOBlock *dev, 
    uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;

    uint64_t total_sectors;



    if (nb_sectors > INT_MAX) {

    if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {

        return false;

    }

    if (sector & dev->sector_mask) {

include/block/block.h

+3 −0
Original line number Diff line number Diff line
@@ -83,6 +83,9 @@ typedef enum { 
#define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)

#define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)



#define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \

                                     INT_MAX >> BDRV_SECTOR_BITS)



/*

 * Allocation status flags

 * BDRV_BLOCK_DATA: data is read from bs->file or another file