Commit 093ea232 authored by Eric Blake's avatar Eric Blake Committed by Max Reitz
Browse files

qemu-io: Allow unaligned access by default 



There's no reason to require the user to specify a flag just so
they can pass in unaligned numbers.  Keep 'read -p' and 'write -p'
as no-ops so that I don't have to hunt down and update all users
of qemu-io, but otherwise make their behavior default as 'read' and
'write'.  Also fix 'write -z', 'readv', 'writev', 'writev',
'aio_read', 'aio_write', and 'aio_write -z'.  For now, 'read -b',
'write -b', and 'write -c' still require alignment (and 'multiwrite',
but that's slated to die soon).

qemu-iotest 23 is updated to match, as the only test that was
previously explicitly expecting an error on an unaligned request.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-id: 1462677405-4752-5-git-send-email-eblake@redhat.com
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent dc38852a

qemu-io-cmds.c

+17 −56
Original line number Diff line number Diff line 
/*

 * Command line utility to exercise the QEMU I/O path.

 *

 * Copyright (C) 2009 Red Hat, Inc.

 * Copyright (C) 2009-2016 Red Hat, Inc.

 * Copyright (c) 2003-2005 Silicon Graphics, Inc.

 *

 * This work is licensed under the terms of the GNU GPL, version 2 or later.
@@ -395,12 +395,6 @@ create_iovec(BlockBackend *blk, QEMUIOVector *qiov, char **argv, int nr_iov, 
            goto fail;

        }



        if (len & 0x1ff) {

            printf("length argument %" PRId64

                   " is not sector aligned\n", len);

            goto fail;

        }



        sizes[i] = len;

        count += len;

    }
@@ -634,7 +628,7 @@ static void read_help(void) 
" -b, -- read from the VM state rather than the virtual disk\n"

" -C, -- report statistics in a machine parsable format\n"

" -l, -- length for pattern verification (only with -P)\n"

" -p, -- allow unaligned access\n"

" -p, -- ignored for backwards compatibility\n"

" -P, -- use a pattern to verify read data\n"

" -q, -- quiet mode, do not show I/O statistics\n"

" -s, -- start offset for pattern verification (only with -P)\n"
@@ -650,7 +644,7 @@ static const cmdinfo_t read_cmd = { 
    .cfunc      = read_f,

    .argmin     = 2,

    .argmax     = -1,

    .args       = "[-abCpqv] [-P pattern [-s off] [-l len]] off len",

    .args       = "[-abCqv] [-P pattern [-s off] [-l len]] off len",

    .oneline    = "reads a number of bytes at a specified offset",

    .help       = read_help,

};
@@ -658,7 +652,7 @@ static const cmdinfo_t read_cmd = { 
static int read_f(BlockBackend *blk, int argc, char **argv)

{

    struct timeval t1, t2;

    bool Cflag = false, pflag = false, qflag = false, vflag = false;

    bool Cflag = false, qflag = false, vflag = false;

    bool Pflag = false, sflag = false, lflag = false, bflag = false;

    int c, cnt;

    char *buf;
@@ -686,7 +680,7 @@ static int read_f(BlockBackend *blk, int argc, char **argv) 
            }

            break;

        case 'p':

            pflag = true;

            /* Ignored for backwards compatibility */

            break;

        case 'P':

            Pflag = true;
@@ -718,11 +712,6 @@ static int read_f(BlockBackend *blk, int argc, char **argv) 
        return qemuio_command_usage(&read_cmd);

    }



    if (bflag && pflag) {

        printf("-b and -p cannot be specified at the same time\n");

        return 0;

    }



    offset = cvtnum(argv[optind]);

    if (offset < 0) {

        print_cvtnum_err(offset, argv[optind]);
@@ -753,7 +742,7 @@ static int read_f(BlockBackend *blk, int argc, char **argv) 
        return 0;

    }



    if (!pflag) {

    if (bflag) {

        if (offset & 0x1ff) {

            printf("offset %" PRId64 " is not sector aligned\n",

                   offset);
@@ -890,12 +879,6 @@ static int readv_f(BlockBackend *blk, int argc, char **argv) 
    }

    optind++;



    if (offset & 0x1ff) {

        printf("offset %" PRId64 " is not sector aligned\n",

               offset);

        return 0;

    }



    nr_iov = argc - optind;

    buf = create_iovec(blk, &qiov, &argv[optind], nr_iov, 0xab);

    if (buf == NULL) {
@@ -952,7 +935,7 @@ static void write_help(void) 
" filled with a set pattern (0xcdcdcdcd).\n"

" -b, -- write to the VM state rather than the virtual disk\n"

" -c, -- write compressed data with blk_write_compressed\n"

" -p, -- allow unaligned access\n"

" -p, -- ignored for backwards compatibility\n"

" -P, -- use different pattern to fill file\n"

" -C, -- report statistics in a machine parsable format\n"

" -q, -- quiet mode, do not show I/O statistics\n"
@@ -968,7 +951,7 @@ static const cmdinfo_t write_cmd = { 
    .cfunc      = write_f,

    .argmin     = 2,

    .argmax     = -1,

    .args       = "[-bcCpqz] [-P pattern ] off len",

    .args       = "[-bcCqz] [-P pattern] off len",

    .oneline    = "writes a number of bytes at a specified offset",

    .help       = write_help,

};
@@ -976,7 +959,7 @@ static const cmdinfo_t write_cmd = { 
static int write_f(BlockBackend *blk, int argc, char **argv)

{

    struct timeval t1, t2;

    bool Cflag = false, pflag = false, qflag = false, bflag = false;

    bool Cflag = false, qflag = false, bflag = false;

    bool Pflag = false, zflag = false, cflag = false;

    int c, cnt;

    char *buf = NULL;
@@ -998,7 +981,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
            Cflag = true;

            break;

        case 'p':

            pflag = true;

            /* Ignored for backwards compatibility */

            break;

        case 'P':

            Pflag = true;
@@ -1022,8 +1005,8 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
        return qemuio_command_usage(&write_cmd);

    }



    if (bflag + pflag + zflag > 1) {

        printf("-b, -p, or -z cannot be specified at the same time\n");

    if (bflag && zflag) {

        printf("-b and -z cannot be specified at the same time\n");

        return 0;

    }
@@ -1049,7 +1032,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
        return 0;

    }



    if (!pflag) {

    if (bflag || cflag) {

        if (offset & 0x1ff) {

            printf("offset %" PRId64 " is not sector aligned\n",

                   offset);
@@ -1173,12 +1156,6 @@ static int writev_f(BlockBackend *blk, int argc, char **argv) 
    }

    optind++;



    if (offset & 0x1ff) {

        printf("offset %" PRId64 " is not sector aligned\n",

               offset);

        return 0;

    }



    nr_iov = argc - optind;

    buf = create_iovec(blk, &qiov, &argv[optind], nr_iov, pattern);

    if (buf == NULL) {
@@ -1533,14 +1510,6 @@ static int aio_read_f(BlockBackend *blk, int argc, char **argv) 
    }

    optind++;



    if (ctx->offset & 0x1ff) {

        printf("offset %" PRId64 " is not sector aligned\n",

               ctx->offset);

        block_acct_invalid(blk_get_stats(blk), BLOCK_ACCT_READ);

        g_free(ctx);

        return 0;

    }



    nr_iov = argc - optind;

    ctx->buf = create_iovec(blk, &ctx->qiov, &argv[optind], nr_iov, 0xab);

    if (ctx->buf == NULL) {
@@ -1645,14 +1614,6 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv) 
    }

    optind++;



    if (ctx->offset & 0x1ff) {

        printf("offset %" PRId64 " is not sector aligned\n",

               ctx->offset);

        block_acct_invalid(blk_get_stats(blk), BLOCK_ACCT_WRITE);

        g_free(ctx);

        return 0;

    }



    if (ctx->zflag) {

        int64_t count = cvtnum(argv[optind]);

        if (count < 0) {

tests/qemu-iotests/023.out

+1444 −724

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