Commit 4d731510 authored by Denis Plotnikov's avatar Denis Plotnikov Committed by Max Reitz
Browse files

qemu-io: add pattern file for write command 



The patch allows to provide a pattern file for write
command. There was no similar ability before.

Signed-off-by: default avatarDenis Plotnikov <dplotnikov@virtuozzo.com>
Message-id: 20190820164616.4072-1-dplotnikov@virtuozzo.com
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
[mreitz: Keep optstring in alphabetical order]
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent 54b89db5

qemu-io-cmds.c

+93 −6
Original line number Diff line number Diff line
@@ -350,6 +350,79 @@ static void qemu_io_free(void *p) 
    qemu_vfree(p);

}



/*

 * qemu_io_alloc_from_file()

 *

 * Allocates the buffer and populates it with the content of the given file

 * up to @len bytes. If the file length is less than @len, then the buffer

 * is populated with the file content cyclically.

 *

 * @blk - the block backend where the buffer content is going to be written to

 * @len - the buffer length

 * @file_name - the file to read the content from

 *

 * Returns: the buffer pointer on success

 *          NULL on error

 */

static void *qemu_io_alloc_from_file(BlockBackend *blk, size_t len,

                                     const char *file_name)

{

    char *buf, *buf_origin;

    FILE *f = fopen(file_name, "r");

    int pattern_len;



    if (!f) {

        perror(file_name);

        return NULL;

    }



    if (qemuio_misalign) {

        len += MISALIGN_OFFSET;

    }



    buf_origin = buf = blk_blockalign(blk, len);



    if (qemuio_misalign) {

        buf_origin += MISALIGN_OFFSET;

        buf += MISALIGN_OFFSET;

        len -= MISALIGN_OFFSET;

    }



    pattern_len = fread(buf_origin, 1, len, f);



    if (ferror(f)) {

        perror(file_name);

        goto error;

    }



    if (pattern_len == 0) {

        fprintf(stderr, "%s: file is empty\n", file_name);

        goto error;

    }



    fclose(f);



    if (len > pattern_len) {

        len -= pattern_len;

        buf += pattern_len;



        while (len > 0) {

            size_t len_to_copy = MIN(pattern_len, len);



            memcpy(buf, buf_origin, len_to_copy);



            len -= len_to_copy;

            buf += len_to_copy;

        }

    }



    return buf_origin;



error:

    qemu_io_free(buf_origin);

    return NULL;

}



static void dump_buffer(const void *buffer, int64_t offset, int64_t len)

{

    uint64_t i;
@@ -948,6 +1021,7 @@ static void write_help(void) 
" -n, -- with -z, don't allow slow fallback\n"

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

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

" -s, -- use a pattern file to fill the write buffer\n"

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

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

" -u, -- with -z, allow unmapping\n"
@@ -964,7 +1038,7 @@ static const cmdinfo_t write_cmd = { 
    .perm       = BLK_PERM_WRITE,

    .argmin     = 2,

    .argmax     = -1,

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

    .args       = "[-bcCfnquz] [-P pattern | -s source_file] off len",

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

    .help       = write_help,

};
@@ -973,7 +1047,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
{

    struct timespec t1, t2;

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

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

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

    int flags = 0;

    int c, cnt, ret;

    char *buf = NULL;
@@ -982,8 +1056,9 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
    /* Some compilers get confused and warn if this is not initialized.  */

    int64_t total = 0;

    int pattern = 0xcd;

    const char *file_name = NULL;



    while ((c = getopt(argc, argv, "bcCfnpP:quz")) != -1) {

    while ((c = getopt(argc, argv, "bcCfnpP:qs:uz")) != -1) {

        switch (c) {

        case 'b':

            bflag = true;
@@ -1013,6 +1088,10 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
        case 'q':

            qflag = true;

            break;

        case 's':

            sflag = true;

            file_name = optarg;

            break;

        case 'u':

            flags |= BDRV_REQ_MAY_UNMAP;

            break;
@@ -1050,8 +1129,9 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
        return -EINVAL;

    }



    if (zflag && Pflag) {

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

    if (zflag + Pflag + sflag > 1) {

        printf("Only one of -z, -P, and -s "

               "can be specified at the same time\n");

        return -EINVAL;

    }
@@ -1087,8 +1167,15 @@ static int write_f(BlockBackend *blk, int argc, char **argv) 
    }



    if (!zflag) {

        if (sflag) {

            buf = qemu_io_alloc_from_file(blk, count, file_name);

            if (!buf) {

                return -EINVAL;

            }

        } else {

            buf = qemu_io_alloc(blk, count, pattern);

        }

    }



    clock_gettime(CLOCK_MONOTONIC, &t1);

    if (bflag) {