[Qemu-devel] [PATCH 0/2] SaveVM: Remove ram support for v1 and v2

[Qemu-devel] [PATCH 0/2] SaveVM: Remove ram support for v1 and v2

[Juan Quintela]

Hi

SaveVM don't work for v2 since at least April.

>From commit message of removal of v2:

It don't work.  It fails in this check

        if (qemu_get_be32(f) != last_ram_offset)

With 512MB of ram, values were for me:

	v = 20c00000 last_ram_offset = 20840000

Last time that some code changed that was this one.

    commit 94a6b54fd6d2d3321066cb4db7abeeb417af9365
    Implement dynamic guest ram allocation.
    (I.e. it has been broken since at least April)

Going back to the previous commit, ram load correctly, but vga screen gets
corrupted and ide don't load correctly.  At this point I decide that removing
support is the only viable thing.

The last user of the ram_compress_* were RAM_SAVE_FLAG_FULL flag, but
that flag was never ever been stored in an image. Mark the flag obsolete
and remove the functions.


Later, Juan.

Juan Quintela (2):
  ram: remove support for loading v1
  ram: Remove SaveVM Version 2 support

 vl.c |  136 +-----------------------------------------------------------------
 1 files changed, 1 insertions(+), 135 deletions(-)

[Qemu-devel] [PATCH 1/2] ram: remove support for loading v1

[Juan Quintela]

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 vl.c |   42 ------------------------------------------
 1 files changed, 0 insertions(+), 42 deletions(-)

diff --git a/vl.c b/vl.c
index 098daaa..4f8a91a 100644
--- a/vl.c
+++ b/vl.c
@@ -2874,45 +2874,6 @@ void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
 /***********************************************************/
 /* ram save/restore */

-static int ram_get_page(QEMUFile *f, uint8_t *buf, int len)
-{
-    int v;
-
-    v = qemu_get_byte(f);
-    switch(v) {
-    case 0:
-        if (qemu_get_buffer(f, buf, len) != len)
-            return -EIO;
-        break;
-    case 1:
-        v = qemu_get_byte(f);
-        memset(buf, v, len);
-        break;
-    default:
-        return -EINVAL;
-    }
-
-    if (qemu_file_has_error(f))
-        return -EIO;
-
-    return 0;
-}
-
-static int ram_load_v1(QEMUFile *f, void *opaque)
-{
-    int ret;
-    ram_addr_t i;
-
-    if (qemu_get_be32(f) != last_ram_offset)
-        return -EINVAL;
-    for(i = 0; i < last_ram_offset; i+= TARGET_PAGE_SIZE) {
-        ret = ram_get_page(f, qemu_get_ram_ptr(i), TARGET_PAGE_SIZE);
-        if (ret)
-            return ret;
-    }
-    return 0;
-}
-
 #define BDRV_HASH_BLOCK_SIZE 1024
 #define IOBUF_SIZE 4096
 #define RAM_CBLOCK_MAGIC 0xfabe
@@ -3147,9 +3108,6 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
     ram_addr_t addr;
     int flags;

-    if (version_id == 1)
-        return ram_load_v1(f, opaque);
-
     if (version_id == 2) {
         if (qemu_get_be32(f) != last_ram_offset)
             return -EINVAL;
-- 
1.6.2.5

[Qemu-devel] [PATCH 2/2] ram: Remove SaveVM Version 2 support

[Juan Quintela]

It don't work.  It fails in this check

        if (qemu_get_be32(f) != last_ram_offset)

With 512MB of ram, values were for me:

	v = 20c00000 last_ram_offset = 20840000

Last time that some code changed that was this one.

    commit 94a6b54fd6d2d3321066cb4db7abeeb417af9365
    Implement dynamic guest ram allocation.
    (I.e. it has been broken since at least April)

Going back to the previous commit, ram load correctly, but vga screen gets
corrupted and ide don't load correctly.  At this point I decide that removing
support is the only viable thing.

The last user of the ram_compress_* were RAM_SAVE_FLAG_FULL flag, but
that flag was never ever been stored in an image. Mark the flag obsolete
and remove the functions.

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 vl.c |   94 +-----------------------------------------------------------------
 1 files changed, 1 insertions(+), 93 deletions(-)

diff --git a/vl.c b/vl.c
index 4f8a91a..8bce394 100644
--- a/vl.c
+++ b/vl.c
@@ -2874,58 +2874,7 @@ void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
 /***********************************************************/
 /* ram save/restore */

-#define BDRV_HASH_BLOCK_SIZE 1024
-#define IOBUF_SIZE 4096
-#define RAM_CBLOCK_MAGIC 0xfabe
-
-typedef struct RamDecompressState {
-    z_stream zstream;
-    QEMUFile *f;
-    uint8_t buf[IOBUF_SIZE];
-} RamDecompressState;
-
-static int ram_decompress_open(RamDecompressState *s, QEMUFile *f)
-{
-    int ret;
-    memset(s, 0, sizeof(*s));
-    s->f = f;
-    ret = inflateInit(&s->zstream);
-    if (ret != Z_OK)
-        return -1;
-    return 0;
-}
-
-static int ram_decompress_buf(RamDecompressState *s, uint8_t *buf, int len)
-{
-    int ret, clen;
-
-    s->zstream.avail_out = len;
-    s->zstream.next_out = buf;
-    while (s->zstream.avail_out > 0) {
-        if (s->zstream.avail_in == 0) {
-            if (qemu_get_be16(s->f) != RAM_CBLOCK_MAGIC)
-                return -1;
-            clen = qemu_get_be16(s->f);
-            if (clen > IOBUF_SIZE)
-                return -1;
-            qemu_get_buffer(s->f, s->buf, clen);
-            s->zstream.avail_in = clen;
-            s->zstream.next_in = s->buf;
-        }
-        ret = inflate(&s->zstream, Z_PARTIAL_FLUSH);
-        if (ret != Z_OK && ret != Z_STREAM_END) {
-            return -1;
-        }
-    }
-    return 0;
-}
-
-static void ram_decompress_close(RamDecompressState *s)
-{
-    inflateEnd(&s->zstream);
-}
-
-#define RAM_SAVE_FLAG_FULL	0x01
+#define RAM_SAVE_FLAG_FULL	0x01 /* Obsolete, not used anymore */
 #define RAM_SAVE_FLAG_COMPRESS	0x02
 #define RAM_SAVE_FLAG_MEM_SIZE	0x04
 #define RAM_SAVE_FLAG_PAGE	0x08
@@ -3073,47 +3022,11 @@ static int ram_save_live(QEMUFile *f, int stage, void *opaque)
     return (stage == 2) && (expected_time <= migrate_max_downtime());
 }

-static int ram_load_dead(QEMUFile *f, void *opaque)
-{
-    RamDecompressState s1, *s = &s1;
-    uint8_t buf[10];
-    ram_addr_t i;
-
-    if (ram_decompress_open(s, f) < 0)
-        return -EINVAL;
-    for(i = 0; i < last_ram_offset; i+= BDRV_HASH_BLOCK_SIZE) {
-        if (ram_decompress_buf(s, buf, 1) < 0) {
-            fprintf(stderr, "Error while reading ram block header\n");
-            goto error;
-        }
-        if (buf[0] == 0) {
-            if (ram_decompress_buf(s, qemu_get_ram_ptr(i),
-                                   BDRV_HASH_BLOCK_SIZE) < 0) {
-                fprintf(stderr, "Error while reading ram block address=0x%08" PRIx64, (uint64_t)i);
-                goto error;
-            }
-        } else {
-        error:
-            printf("Error block header\n");
-            return -EINVAL;
-        }
-    }
-    ram_decompress_close(s);
-
-    return 0;
-}
-
 static int ram_load(QEMUFile *f, void *opaque, int version_id)
 {
     ram_addr_t addr;
     int flags;

-    if (version_id == 2) {
-        if (qemu_get_be32(f) != last_ram_offset)
-            return -EINVAL;
-        return ram_load_dead(f, opaque);
-    }
-
     if (version_id != 3)
         return -EINVAL;

@@ -3128,11 +3041,6 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
                 return -EINVAL;
         }

-        if (flags & RAM_SAVE_FLAG_FULL) {
-            if (ram_load_dead(f, opaque) < 0)
-                return -EINVAL;
-        }
-        
         if (flags & RAM_SAVE_FLAG_COMPRESS) {
             uint8_t ch = qemu_get_byte(f);
             memset(qemu_get_ram_ptr(addr), ch, TARGET_PAGE_SIZE);
-- 
1.6.2.5