From 4d731510d34f280ed45a6de621d016f67a49ea48 Mon Sep 17 00:00:00 2001 From: Denis Plotnikov Date: Tue, 20 Aug 2019 19:46:16 +0300 Subject: [PATCH] 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: Denis Plotnikov Message-id: 20190820164616.4072-1-dplotnikov@virtuozzo.com Reviewed-by: Eric Blake [mreitz: Keep optstring in alphabetical order] Signed-off-by: Max Reitz --- qemu-io-cmds.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 93 insertions(+), 6 deletions(-) diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c index 8904733961..d46fa166d3 100644 --- a/qemu-io-cmds.c +++ b/qemu-io-cmds.c @@ -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; } @@ -1087,7 +1167,14 @@ static int write_f(BlockBackend *blk, int argc, char **argv) } if (!zflag) { - buf = qemu_io_alloc(blk, count, pattern); + 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);