Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-pull-request' into...

[mirror_qemu.git] / block / cloop.c

diff --git a/block/cloop.c b/block/cloop.c
index 41bdee8d7ffe91538becfe5b62fc0260fdd550d4..384c9735bbe3c4e6657b1663c9f7285140a5a9eb 100644 (file)
--- a/block/cloop.c
+++ b/block/cloop.c
@@ -22,9 +22,11 @@
  * THE SOFTWARE.
  */
 #include "qemu/osdep.h"
-#include "qemu-common.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
 #include "block/block_int.h"
 #include "qemu/module.h"
+#include "qemu/bswap.h"
 #include <zlib.h>
 
 /* Maximum compressed block size */
@@ -64,10 +66,19 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
     uint32_t offsets_size, max_compressed_block_size = 1, i;
     int ret;
 
-    bs->read_only = 1;
+    ret = bdrv_apply_auto_read_only(bs, NULL, errp);
+    if (ret < 0) {
+        return ret;
+    }
+
+    bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+                               false, errp);
+    if (!bs->file) {
+        return -EINVAL;
+    }
 
     /* read header */
-    ret = bdrv_pread(bs->file->bs, 128, &s->block_size, 4);
+    ret = bdrv_pread(bs->file, 128, &s->block_size, 4);
     if (ret < 0) {
         return ret;
     }
@@ -93,7 +104,7 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
         return -EINVAL;
     }
 
-    ret = bdrv_pread(bs->file->bs, 128 + 4, &s->n_blocks, 4);
+    ret = bdrv_pread(bs->file, 128 + 4, &s->n_blocks, 4);
     if (ret < 0) {
         return ret;
     }
@@ -124,7 +135,7 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
         return -ENOMEM;
     }
 
-    ret = bdrv_pread(bs->file->bs, 128 + 4 + 4, s->offsets, offsets_size);
+    ret = bdrv_pread(bs->file, 128 + 4 + 4, s->offsets, offsets_size);
     if (ret < 0) {
         goto fail;
     }
@@ -196,6 +207,11 @@ fail:
     return ret;
 }
 
+static void cloop_refresh_limits(BlockDriverState *bs, Error **errp)
+{
+    bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */
+}
+
 static inline int cloop_read_block(BlockDriverState *bs, int block_num)
 {
     BDRVCloopState *s = bs->opaque;
@@ -204,7 +220,7 @@ static inline int cloop_read_block(BlockDriverState *bs, int block_num)
         int ret;
         uint32_t bytes = s->offsets[block_num + 1] - s->offsets[block_num];
 
-        ret = bdrv_pread(bs->file->bs, s->offsets[block_num],
+        ret = bdrv_pread(bs->file, s->offsets[block_num],
                          s->compressed_block, bytes);
         if (ret != bytes) {
             return -1;
@@ -228,33 +244,38 @@ static inline int cloop_read_block(BlockDriverState *bs, int block_num)
     return 0;
 }
 
-static int cloop_read(BlockDriverState *bs, int64_t sector_num,
-                    uint8_t *buf, int nb_sectors)
+static int coroutine_fn
+cloop_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
+                QEMUIOVector *qiov, int flags)
 {
     BDRVCloopState *s = bs->opaque;
-    int i;
+    uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
+    int nb_sectors = bytes >> BDRV_SECTOR_BITS;
+    int ret, i;
+
+    assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
+    assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
+
+    qemu_co_mutex_lock(&s->lock);
 
     for (i = 0; i < nb_sectors; i++) {
+        void *data;
         uint32_t sector_offset_in_block =
             ((sector_num + i) % s->sectors_per_block),
             block_num = (sector_num + i) / s->sectors_per_block;
         if (cloop_read_block(bs, block_num) != 0) {
-            return -1;
+            ret = -EIO;
+            goto fail;
         }
-        memcpy(buf + i * 512,
-            s->uncompressed_block + sector_offset_in_block * 512, 512);
+
+        data = s->uncompressed_block + sector_offset_in_block * 512;
+        qemu_iovec_from_buf(qiov, i * 512, data, 512);
     }
-    return 0;
-}
 
-static coroutine_fn int cloop_co_read(BlockDriverState *bs, int64_t sector_num,
-                                      uint8_t *buf, int nb_sectors)
-{
-    int ret;
-    BDRVCloopState *s = bs->opaque;
-    qemu_co_mutex_lock(&s->lock);
-    ret = cloop_read(bs, sector_num, buf, nb_sectors);
+    ret = 0;
+fail:
     qemu_co_mutex_unlock(&s->lock);
+
     return ret;
 }
 
@@ -272,7 +293,9 @@ static BlockDriver bdrv_cloop = {
     .instance_size  = sizeof(BDRVCloopState),
     .bdrv_probe     = cloop_probe,
     .bdrv_open      = cloop_open,
-    .bdrv_read      = cloop_co_read,
+    .bdrv_child_perm     = bdrv_format_default_perms,
+    .bdrv_refresh_limits = cloop_refresh_limits,
+    .bdrv_co_preadv = cloop_co_preadv,
     .bdrv_close     = cloop_close,
 };