From ddb1e6862dffe40bb2929d3a0e3eba198c54ee43 Mon Sep 17 00:00:00 2001

From: Max Reitz <mreitz@redhat.com>

Date: Mon, 10 Nov 2014 09:14:07 +0100

Subject: [PATCH 30/41] qcow2: Add falloc and full preallocation option

Message-id: <1415610847-15383-5-git-send-email-mreitz@redhat.com>

Patchwork-id: 62240

O-Subject: [RHEL-7.1 qemu-kvm PATCH v2 4/4] qcow2: Add falloc and full preallocation option

Bugzilla: 1087724

RH-Acked-by: Laszlo Ersek <lersek@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

From: Hu Tao <hutao@cn.fujitsu.com>

preallocation=falloc allocates disk space by posix_fallocate(),

preallocation=full allocates disk space by writing zeros to disk.

Both modes imply preallocation=metadata.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>

Reviewed-by: Max Reitz <mreitz@redhat.com>

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

(cherry picked from commit 0e4271b711a8ea766d29824c844e268b91ac3ae5)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

Conflicts:

	block/qcow2.c

QEMUOptionParameter has not been replaced with QemuOpts downstream,

total_size is in sectors instead of bytes in downstream's

qcow2_create2().

The use of QEMUOptionParameter makes it rather difficult to set an

option in qcow2 for the underlying file to be created. Because qcow2

already used to pass a functionally empty options array, I added an

assertion for this to be true and created a new QEMUOptionParameter

array in case there are actually options to be passed to the protocol

driver (that is, for preallocation).

Signed-off-by: Max Reitz <mreitz@redhat.com>

---

 block/qcow2.c              | 81 +++++++++++++++++++++++++++++++++++++++-------

 qemu-doc.texi              |  8 +++--

 qemu-img.texi              |  8 +++--

 tests/qemu-iotests/082.out | 54 +++++++++++++++----------------

 4 files changed, 106 insertions(+), 45 deletions(-)

diff --git a/block/qcow2.c b/block/qcow2.c

index 99c6b93..43e54d6 100644

--- a/block/qcow2.c

+++ b/block/qcow2.c

@@ -1557,8 +1557,7 @@ static int preallocate(BlockDriverState *bs)

 static int qcow2_create2(const char *filename, int64_t total_size,

                          const char *backing_file, const char *backing_format,

                          int flags, size_t cluster_size, PreallocMode prealloc,

-                         QEMUOptionParameter *options, int version,

-                         Error **errp)

+                         int version, Error **errp)

 {

     /* Calculate cluster_bits */

     int cluster_bits;

@@ -1588,8 +1587,71 @@ static int qcow2_create2(const char *filename, int64_t total_size,

     uint64_t* refcount_table;

     Error *local_err = NULL;

     int ret;

+    QEMUOptionParameter *options = NULL;

+    BlockDriver *file_drv;

+

+    if (prealloc == PREALLOC_MODE_FULL || prealloc == PREALLOC_MODE_FALLOC) {

+        int64_t meta_size = 0;

+        uint64_t nreftablee, nrefblocke, nl1e, nl2e;

+        int64_t aligned_total_size = align_offset(total_size * BDRV_SECTOR_SIZE,

+                                                  cluster_size);

+

+        /* header: 1 cluster */

+        meta_size += cluster_size;

+

+        /* total size of L2 tables */

+        nl2e = aligned_total_size / cluster_size;

+        nl2e = align_offset(nl2e, cluster_size / sizeof(uint64_t));

+        meta_size += nl2e * sizeof(uint64_t);

+

+        /* total size of L1 tables */

+        nl1e = nl2e * sizeof(uint64_t) / cluster_size;

+        nl1e = align_offset(nl1e, cluster_size / sizeof(uint64_t));

+        meta_size += nl1e * sizeof(uint64_t);

+

+        /* total size of refcount blocks

+         *

+         * note: every host cluster is reference-counted, including metadata

+         * (even refcount blocks are recursively included).

+         * Let:

+         *   a = total_size * BDRV_SECTOR_SIZE (this is the guest disk size)

+         *   m = meta size not including refcount blocks and refcount tables

+         *   c = cluster size

+         *   y1 = number of refcount blocks entries

+         *   y2 = meta size including everything

+         * then,

+         *   y1 = (y2 + a)/c

+         *   y2 = y1 * sizeof(u16) + y1 * sizeof(u16) * sizeof(u64) / c + m

+         * we can get y1:

+         *   y1 = (a + m) / (c - sizeof(u16) - sizeof(u16) * sizeof(u64) / c)

+         */

+        nrefblocke = (aligned_total_size + meta_size + cluster_size) /

+            (cluster_size - sizeof(uint16_t) -

+             1.0 * sizeof(uint16_t) * sizeof(uint64_t) / cluster_size);

+        nrefblocke = align_offset(nrefblocke, cluster_size / sizeof(uint16_t));

+        meta_size += nrefblocke * sizeof(uint16_t);

+

+        /* total size of refcount tables */

+        nreftablee = nrefblocke * sizeof(uint16_t) / cluster_size;

+        nreftablee = align_offset(nreftablee, cluster_size / sizeof(uint64_t));

+        meta_size += nreftablee * sizeof(uint64_t);

+

+        file_drv = bdrv_find_protocol(filename, true);

+        if (file_drv == NULL) {

+            error_setg(errp, "Could not find protocol for file '%s'", filename);

+            return -ENOENT;

+        }

+

+        options = append_option_parameters(options, file_drv->create_options);

+

+        set_option_parameter_int(options, BLOCK_OPT_SIZE,

+                                 aligned_total_size + meta_size);

+        set_option_parameter(options, BLOCK_OPT_PREALLOC,

+                             PreallocMode_lookup[prealloc]);

+    }

     ret = bdrv_create_file(filename, options, &local_err);

+    free_option_parameters(options);

     if (ret < 0) {

         error_propagate(errp, local_err);

         return ret;

@@ -1691,7 +1753,7 @@ static int qcow2_create2(const char *filename, int64_t total_size,

     }

     /* And if we're supposed to preallocate metadata, do that now */

-    if (prealloc == PREALLOC_MODE_METADATA) {

+    if (prealloc != PREALLOC_MODE_OFF) {

         BDRVQcowState *s = bs->opaque;

         qemu_co_mutex_lock(&s->lock);

         ret = preallocate(bs);

@@ -1761,13 +1823,6 @@ static int qcow2_create(const char *filename, QEMUOptionParameter *options,

         options++;

     }

-    if (prealloc != PREALLOC_MODE_OFF &&

-        prealloc != PREALLOC_MODE_METADATA) {

-        error_setg(errp, "Unsupported preallocate mode: %s",

-                   PreallocMode_lookup[prealloc]);

-        return -EINVAL;

-    }

-

     if (backing_file && prealloc != PREALLOC_MODE_OFF) {

         error_setg(errp, "Backing file and preallocation cannot be used at "

                    "the same time");

@@ -1780,8 +1835,9 @@ static int qcow2_create(const char *filename, QEMUOptionParameter *options,

         return -EINVAL;

     }

+    assert(!options || !options->name);

     ret = qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,

-                        cluster_size, prealloc, options, version, &local_err);

+                        cluster_size, prealloc, version, &local_err);

     if (error_is_set(&local_err)) {

         error_propagate(errp, local_err);

     }

@@ -2315,7 +2371,8 @@ static QEMUOptionParameter qcow2_create_options[] = {

     {

         .name = BLOCK_OPT_PREALLOC,

         .type = OPT_STRING,

-        .help = "Preallocation mode (allowed values: off, metadata)"

+        .help = "Preallocation mode (allowed values: off, metadata, "

+                "falloc, full)"

     },

     {

         .name = BLOCK_OPT_LAZY_REFCOUNTS,

diff --git a/qemu-doc.texi b/qemu-doc.texi

index dc5b49e..0f7e5f8 100644

--- a/qemu-doc.texi

+++ b/qemu-doc.texi

@@ -567,9 +567,11 @@ sizes can improve the image file size whereas larger cluster sizes generally

 provide better performance.

 @item preallocation

-Preallocation mode (allowed values: off, metadata). An image with preallocated

-metadata is initially larger but can improve performance when the image needs

-to grow.

+Preallocation mode (allowed values: @code{off}, @code{metadata}, @code{falloc},

+@code{full}). An image with preallocated metadata is initially larger but can

+improve performance when the image needs to grow. @code{falloc} and @code{full}

+preallocations are like the same options of @code{raw} format, but sets up

+metadata also.

 @item lazy_refcounts

 If this option is set to @code{on}, reference count updates are postponed with

diff --git a/qemu-img.texi b/qemu-img.texi

index 80d3261..e943856 100644

--- a/qemu-img.texi

+++ b/qemu-img.texi

@@ -432,9 +432,11 @@ sizes can improve the image file size whereas larger cluster sizes generally

 provide better performance.

 @item preallocation

-Preallocation mode (allowed values: off, metadata). An image with preallocated

-metadata is initially larger but can improve performance when the image needs

-to grow.

+Preallocation mode (allowed values: @code{off}, @code{metadata}, @code{falloc},

+@code{full}). An image with preallocated metadata is initially larger but can

+improve performance when the image needs to grow. @code{falloc} and @code{full}

+preallocations are like the same options of @code{raw} format, but sets up

+metadata also.

 @item lazy_refcounts

 If this option is set to @code{on}, reference count updates are postponed with

diff --git a/tests/qemu-iotests/082.out b/tests/qemu-iotests/082.out

index d71610b..8abfde7 100644

--- a/tests/qemu-iotests/082.out

+++ b/tests/qemu-iotests/082.out

@@ -64,7 +64,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o ? TEST_DIR/t.qcow2 128M

@@ -75,7 +75,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2 128M

@@ -86,7 +86,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2 128M

@@ -97,7 +97,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2 128M

@@ -108,7 +108,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2 128M

@@ -119,7 +119,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2 128M

@@ -130,7 +130,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2 128M

@@ -141,7 +141,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -f qcow2 -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 128M

@@ -167,7 +167,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: create -o help

@@ -245,7 +245,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o ? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -256,7 +256,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -267,7 +267,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -278,7 +278,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -289,7 +289,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -300,7 +300,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -311,7 +311,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -322,7 +322,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -O qcow2 -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base

@@ -348,7 +348,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -o help

@@ -415,7 +415,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o ? TEST_DIR/t.qcow2

@@ -426,7 +426,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2

@@ -437,7 +437,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2

@@ -448,7 +448,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2

@@ -459,7 +459,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2

@@ -470,7 +470,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2

@@ -481,7 +481,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2

@@ -492,7 +492,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: amend -f qcow2 -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2

@@ -520,7 +520,7 @@ backing_file     File name of a base image

 backing_fmt      Image format of the base image

 encryption       Encrypt the image

 cluster_size     qcow2 cluster size

-preallocation    Preallocation mode (allowed values: off, metadata)

+preallocation    Preallocation mode (allowed values: off, metadata, falloc, full)

 lazy_refcounts   Postpone refcount updates

 Testing: convert -o help

-- 

1.8.3.1