[Qemu-devel] [PATCH v2] LUKS: support preallocation in qemu-img

[Maxim Levitsky]

preallocation=off and preallocation=metadata
both allocate luks header only, and preallocation=falloc/full
is passed to underlying file.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1534951

Signed-off-by: Maxim Levitsky <address@hidden>
---
 block/crypto.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/block/crypto.c b/block/crypto.c
index 8237424ae6..cbc291301e 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -74,6 +74,7 @@ static ssize_t block_crypto_read_func(QCryptoBlock *block,
 struct BlockCryptoCreateData {
     BlockBackend *blk;
     uint64_t size;
+    PreallocMode prealloc;
 };
 
 
@@ -112,7 +113,7 @@ static ssize_t block_crypto_init_func(QCryptoBlock *block,
      * available to the guest, so we must take account of that
      * which will be used by the crypto header
      */
-    return blk_truncate(data->blk, data->size + headerlen, PREALLOC_MODE_OFF,
+    return blk_truncate(data->blk, data->size + headerlen, data->prealloc,
                         errp);
 }
 
@@ -251,6 +252,7 @@ static int block_crypto_open_generic(QCryptoBlockFormat 
format,
 static int block_crypto_co_create_generic(BlockDriverState *bs,
                                           int64_t size,
                                           QCryptoBlockCreateOptions *opts,
+                                          PreallocMode prealloc,
                                           Error **errp)
 {
     int ret;
@@ -269,6 +271,7 @@ static int block_crypto_co_create_generic(BlockDriverState 
*bs,
     data = (struct BlockCryptoCreateData) {
         .blk = blk,
         .size = size,
+        .prealloc = prealloc,
     };
 
     crypto = qcrypto_block_create(opts, NULL,
@@ -516,7 +519,7 @@ block_crypto_co_create_luks(BlockdevCreateOptions 
*create_options, Error **errp)
     };
 
     ret = block_crypto_co_create_generic(bs, luks_opts->size, &create_opts,
-                                         errp);
+                                         PREALLOC_MODE_OFF, errp);
     if (ret < 0) {
         goto fail;
     }
@@ -534,12 +537,28 @@ static int coroutine_fn 
block_crypto_co_create_opts_luks(const char *filename,
     QCryptoBlockCreateOptions *create_opts = NULL;
     BlockDriverState *bs = NULL;
     QDict *cryptoopts;
+    PreallocMode prealloc;
+    char *buf = NULL;
     int64_t size;
     int ret;
+    Error *local_err = NULL;
 
     /* Parse options */
     size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0);
 
+    buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
+    prealloc = qapi_enum_parse(&PreallocMode_lookup, buf,
+                                   PREALLOC_MODE_OFF, &local_err);
+    g_free(buf);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return -EINVAL;
+    }
+
+    if (prealloc == PREALLOC_MODE_METADATA) {
+        prealloc  = PREALLOC_MODE_OFF;
+    }
+
     cryptoopts = qemu_opts_to_qdict_filtered(opts, NULL,
                                              &block_crypto_create_opts_luks,
                                              true);
@@ -565,7 +584,7 @@ static int coroutine_fn 
block_crypto_co_create_opts_luks(const char *filename,
     }
 
     /* Create format layer */
-    ret = block_crypto_co_create_generic(bs, size, create_opts, errp);
+    ret = block_crypto_co_create_generic(bs, size, create_opts, prealloc, 
errp);
     if (ret < 0) {
         goto fail;
     }
-- 
2.17.2