Commit 3d9b4925 authored by Michael Tokarev's avatar Michael Tokarev
Browse files

consolidate qemu_iovec_memset{,_skip}() into single function and use existing iov_memset() 



This patch combines two functions into one, and replaces
the implementation with already existing iov_memset() from
iov.c.

The new prototype of qemu_iovec_memset():
  size_t qemu_iovec_memset(qiov, size_t offset, int fillc, size_t bytes)
It is different from former qemu_iovec_memset_skip(), and
I want to make other functions to be consistent with it
too: first how much to skip, second what, and 3rd how many
of it.  It also returns actual number of bytes filled in,
which may be less than the requested `bytes' if qiov is
smaller than offset+bytes, in the same way iov_memset()
does.

While at it, use utility function iov_memset() from
iov.h in posix-aio-compat.c, where qiov was used.

Signed-off-by: default avatarMichael Tokarev <mjt@tls.msk.ru>
parent 2278a69e

Makefile

+2 −1
Original line number Diff line number Diff line
@@ -154,7 +154,8 @@ qemu-img.o: qemu-img-cmds.h 
qemu-img.o qemu-tool.o qemu-nbd.o qemu-io.o cmd.o qemu-ga.o: $(GENERATED_HEADERS)



tools-obj-y = $(oslib-obj-y) $(trace-obj-y) qemu-tool.o qemu-timer.o \

	qemu-timer-common.o main-loop.o notify.o iohandler.o cutils.o async.o

	qemu-timer-common.o main-loop.o notify.o \

	iohandler.o cutils.o iov.o async.o

tools-obj-$(CONFIG_POSIX) += compatfd.o



qemu-img$(EXESUF): qemu-img.o $(tools-obj-y) $(block-obj-y)

Makefile.objs

+2 −2
Original line number Diff line number Diff line
@@ -42,7 +42,7 @@ coroutine-obj-$(CONFIG_WIN32) += coroutine-win32.o 
#######################################################################

# block-obj-y is code used by both qemu system emulation and qemu-img



block-obj-y = cutils.o cache-utils.o qemu-option.o module.o async.o

block-obj-y = cutils.o iov.o cache-utils.o qemu-option.o module.o async.o

block-obj-y += nbd.o block.o aio.o aes.o qemu-config.o qemu-progress.o qemu-sockets.o

block-obj-y += $(coroutine-obj-y) $(qobject-obj-y) $(version-obj-y)

block-obj-$(CONFIG_POSIX) += posix-aio-compat.o
@@ -198,7 +198,7 @@ common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o xenfb.o xen_disk.o xen_nic.o 
user-obj-y =

user-obj-y += envlist.o path.o

user-obj-y += tcg-runtime.o host-utils.o

user-obj-y += cutils.o cache-utils.o

user-obj-y += cutils.o iov.o cache-utils.o

user-obj-y += module.o

user-obj-y += qemu-user.o

user-obj-y += $(trace-obj-y)

block/qcow2.c

+3 −3
Original line number Diff line number Diff line
@@ -510,7 +510,7 @@ int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, 
    else

        n1 = bs->total_sectors - sector_num;



    qemu_iovec_memset_skip(qiov, 0, 512 * (nb_sectors - n1), 512 * n1);

    qemu_iovec_memset(qiov, 512 * n1, 0, 512 * (nb_sectors - n1));



    return n1;

}
@@ -571,7 +571,7 @@ static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, 
                }

            } else {

                /* Note: in this case, no need to wait */

                qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors);

                qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);

            }

            break;
@@ -580,7 +580,7 @@ static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num, 
                ret = -EIO;

                goto fail;

            }

            qemu_iovec_memset(&hd_qiov, 0, 512 * cur_nr_sectors);

            qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);

            break;



        case QCOW2_CLUSTER_COMPRESSED:

block/qed.c

+2 −2
Original line number Diff line number Diff line
@@ -736,7 +736,7 @@ static void qed_read_backing_file(BDRVQEDState *s, uint64_t pos, 
    /* Zero all sectors if reading beyond the end of the backing file */

    if (pos >= backing_length ||

        pos + qiov->size > backing_length) {

        qemu_iovec_memset(qiov, 0, qiov->size);

        qemu_iovec_memset(qiov, 0, 0, qiov->size);

    }



    /* Complete now if there are no backing file sectors to read */
@@ -1251,7 +1251,7 @@ static void qed_aio_read_data(void *opaque, int ret, 


    /* Handle zero cluster and backing file reads */

    if (ret == QED_CLUSTER_ZERO) {

        qemu_iovec_memset(&acb->cur_qiov, 0, acb->cur_qiov.size);

        qemu_iovec_memset(&acb->cur_qiov, 0, 0, acb->cur_qiov.size);

        qed_aio_next_io(acb, 0);

        return;

    } else if (ret != QED_CLUSTER_FOUND) {

cutils.c

+4 −40
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <math.h>



#include "qemu_socket.h"

#include "iov.h"



void pstrcpy(char *buf, int buf_size, const char *str)

{
@@ -260,47 +261,10 @@ void qemu_iovec_from_buffer(QEMUIOVector *qiov, const void *buf, size_t count) 
    }

}



void qemu_iovec_memset(QEMUIOVector *qiov, int c, size_t count)

size_t qemu_iovec_memset(QEMUIOVector *qiov, size_t offset,

                         int fillc, size_t bytes)

{

    size_t n;

    int i;



    for (i = 0; i < qiov->niov && count; ++i) {

        n = MIN(count, qiov->iov[i].iov_len);

        memset(qiov->iov[i].iov_base, c, n);

        count -= n;

    }

}



void qemu_iovec_memset_skip(QEMUIOVector *qiov, int c, size_t count,

                            size_t skip)

{

    int i;

    size_t done;

    void *iov_base;

    uint64_t iov_len;



    done = 0;

    for (i = 0; (i < qiov->niov) && (done != count); i++) {

        if (skip >= qiov->iov[i].iov_len) {

            /* Skip the whole iov */

            skip -= qiov->iov[i].iov_len;

            continue;

        } else {

            /* Skip only part (or nothing) of the iov */

            iov_base = (uint8_t*) qiov->iov[i].iov_base + skip;

            iov_len = qiov->iov[i].iov_len - skip;

            skip = 0;

        }



        if (done + iov_len > count) {

            memset(iov_base, c, count - done);

            break;

        } else {

            memset(iov_base, c, iov_len);

        }

        done += iov_len;

    }

    return iov_memset(qiov->iov, qiov->niov, offset, fillc, bytes);

}



/*