diff mbox

[v2] sheepdog: add full data preallocation support

Message ID 1309891128-4458-1-git-send-email-morita.kazutaka@lab.ntt.co.jp
State New
Headers show

Commit Message

MORITA Kazutaka July 5, 2011, 6:38 p.m. UTC 
This introduces qemu-img create option for sheepdog which allows the
data to be fully preallocated (note that sheepdog always preallocates
metadata).

The option is disabled by default and you need to enable it like the
following:

qemu-img create sheepdog:test -o preallocation=full 1G

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
---
 block/sheepdog.c |   71 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 files changed, 68 insertions(+), 3 deletions(-)

Comments

Kevin Wolf July 6, 2011, 11:18 a.m. UTC | #1 
Am 05.07.2011 20:38, schrieb MORITA Kazutaka:
> This introduces qemu-img create option for sheepdog which allows the
> data to be fully preallocated (note that sheepdog always preallocates
> metadata).
> 
> The option is disabled by default and you need to enable it like the
> following:
> 
> qemu-img create sheepdog:test -o preallocation=full 1G
> 
> Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

Thanks, applied to the block branch.

Kevin
diff mbox

Patch

diff --git a/block/sheepdog.c b/block/sheepdog.c
index 0392ca8..5b1eb57 100644
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -1292,6 +1292,49 @@  static int do_sd_create(char *filename, int64_t vdi_size,
     return 0;
 }
 
+static int sd_prealloc(const char *filename)
+{
+    BlockDriverState *bs = NULL;
+    uint32_t idx, max_idx;
+    int64_t vdi_size;
+    void *buf = qemu_mallocz(SD_DATA_OBJ_SIZE);
+    int ret;
+
+    ret = bdrv_file_open(&bs, filename, BDRV_O_RDWR);
+    if (ret < 0) {
+        goto out;
+    }
+
+    vdi_size = bdrv_getlength(bs);
+    if (vdi_size < 0) {
+        ret = vdi_size;
+        goto out;
+    }
+    max_idx = DIV_ROUND_UP(vdi_size, SD_DATA_OBJ_SIZE);
+
+    for (idx = 0; idx < max_idx; idx++) {
+        /*
+         * The created image can be a cloned image, so we need to read
+         * a data from the source image.
+         */
+        ret = bdrv_pread(bs, idx * SD_DATA_OBJ_SIZE, buf, SD_DATA_OBJ_SIZE);
+        if (ret < 0) {
+            goto out;
+        }
+        ret = bdrv_pwrite(bs, idx * SD_DATA_OBJ_SIZE, buf, SD_DATA_OBJ_SIZE);
+        if (ret < 0) {
+            goto out;
+        }
+    }
+out:
+    if (bs) {
+        bdrv_delete(bs);
+    }
+    qemu_free(buf);
+
+    return ret;
+}
+
 static int sd_create(const char *filename, QEMUOptionParameter *options)
 {
     int ret;
@@ -1301,13 +1344,15 @@  static int sd_create(const char *filename, QEMUOptionParameter *options)
     BDRVSheepdogState s;
     char vdi[SD_MAX_VDI_LEN], tag[SD_MAX_VDI_TAG_LEN];
     uint32_t snapid;
+    int prealloc = 0;
+    const char *vdiname;
 
-    strstart(filename, "sheepdog:", (const char **)&filename);
+    strstart(filename, "sheepdog:", &vdiname);
 
     memset(&s, 0, sizeof(s));
     memset(vdi, 0, sizeof(vdi));
     memset(tag, 0, sizeof(tag));
-    if (parse_vdiname(&s, filename, vdi, &snapid, tag) < 0) {
+    if (parse_vdiname(&s, vdiname, vdi, &snapid, tag) < 0) {
         error_report("invalid filename\n");
         return -EINVAL;
     }
@@ -1317,6 +1362,16 @@  static int sd_create(const char *filename, QEMUOptionParameter *options)
             vdi_size = options->value.n;
         } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
             backing_file = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
+            if (!options->value.s || !strcmp(options->value.s, "off")) {
+                prealloc = 0;
+            } else if (!strcmp(options->value.s, "full")) {
+                prealloc = 1;
+            } else {
+                error_report("Invalid preallocation mode: '%s'",
+                             options->value.s);
+                return -EINVAL;
+            }
         }
         options++;
     }
@@ -1354,7 +1409,12 @@  static int sd_create(const char *filename, QEMUOptionParameter *options)
         bdrv_delete(bs);
     }
 
-    return do_sd_create((char *)vdi, vdi_size, base_vid, &vid, 0, s.addr, s.port);
+    ret = do_sd_create(vdi, vdi_size, base_vid, &vid, 0, s.addr, s.port);
+    if (!prealloc || ret) {
+        return ret;
+    }
+
+    return sd_prealloc(filename);
 }
 
 static void sd_close(BlockDriverState *bs)
@@ -1990,6 +2050,11 @@  static QEMUOptionParameter sd_create_options[] = {
         .type = OPT_STRING,
         .help = "File name of a base image"
     },
+    {
+        .name = BLOCK_OPT_PREALLOC,
+        .type = OPT_STRING,
+        .help = "Preallocation mode (allowed values: off, full)"
+    },
     { NULL }
 };