From 4e0ebb941ba15c31e7d19d44189bf47fee3181c9 Mon Sep 17 00:00:00 2001
From: Yuan Liu <yuan1.liu@intel.com>
Date: Mon, 10 Jun 2024 18:21:05 +0800
Subject: [73/99] migration/multifd: put IOV initialization into compression
 method

commit d9d3e4f243214f742425d9d8360f0794bb05c999 upstream.

Different compression methods may require different numbers of IOVs.
Based on streaming compression of zlib and zstd, all pages will be
compressed to a data block, so two IOVs are needed for packet header
and compressed data block.

Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Reviewed-by: Nanhai Zou <nanhai.zou@intel.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Jason Zeng <jason.zeng@intel.com>
---
 migration/multifd-zlib.c |  7 +++++++
 migration/multifd-zstd.c |  8 +++++++-
 migration/multifd.c      | 22 ++++++++++++----------
 3 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
index b210725f6e..2df4983780 100644
--- a/migration/multifd-zlib.c
+++ b/migration/multifd-zlib.c
@@ -70,6 +70,10 @@ static int zlib_send_setup(MultiFDSendParams *p, Error **errp)
         goto err_free_zbuff;
     }
     p->compress_data = z;
+
+    /* Needs 2 IOVs, one for packet header and one for compressed data */
+    p->iov = g_new0(struct iovec, 2);
+
     return 0;
 
 err_free_zbuff:
@@ -101,6 +105,9 @@ static void zlib_send_cleanup(MultiFDSendParams *p, Error **errp)
     z->buf = NULL;
     g_free(p->compress_data);
     p->compress_data = NULL;
+
+    g_free(p->iov);
+    p->iov = NULL;
 }
 
 /**
diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
index 256858df0a..ca17b7e310 100644
--- a/migration/multifd-zstd.c
+++ b/migration/multifd-zstd.c
@@ -52,7 +52,6 @@ static int zstd_send_setup(MultiFDSendParams *p, Error **errp)
     struct zstd_data *z = g_new0(struct zstd_data, 1);
     int res;
 
-    p->compress_data = z;
     z->zcs = ZSTD_createCStream();
     if (!z->zcs) {
         g_free(z);
@@ -77,6 +76,10 @@ static int zstd_send_setup(MultiFDSendParams *p, Error **errp)
         error_setg(errp, "multifd %u: out of memory for zbuff", p->id);
         return -1;
     }
+    p->compress_data = z;
+
+    /* Needs 2 IOVs, one for packet header and one for compressed data */
+    p->iov = g_new0(struct iovec, 2);
     return 0;
 }
 
@@ -98,6 +101,9 @@ static void zstd_send_cleanup(MultiFDSendParams *p, Error **errp)
     z->zbuff = NULL;
     g_free(p->compress_data);
     p->compress_data = NULL;
+
+    g_free(p->iov);
+    p->iov = NULL;
 }
 
 /**
diff --git a/migration/multifd.c b/migration/multifd.c
index 4394952fbb..0fcecc3759 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -113,6 +113,13 @@ static int nocomp_send_setup(MultiFDSendParams *p, Error **errp)
         p->write_flags |= QIO_CHANNEL_WRITE_FLAG_ZERO_COPY;
     }
 
+    if (multifd_use_packets()) {
+        /* We need one extra place for the packet header */
+        p->iov = g_new0(struct iovec, p->page_count + 1);
+    } else {
+        p->iov = g_new0(struct iovec, p->page_count);
+    }
+
     return 0;
 }
 
@@ -126,6 +133,8 @@ static int nocomp_send_setup(MultiFDSendParams *p, Error **errp)
  */
 static void nocomp_send_cleanup(MultiFDSendParams *p, Error **errp)
 {
+    g_free(p->iov);
+    p->iov = NULL;
     return;
 }
 
@@ -202,6 +211,7 @@ static int nocomp_send_prepare(MultiFDSendParams *p, Error **errp)
  */
 static int nocomp_recv_setup(MultiFDRecvParams *p, Error **errp)
 {
+    p->iov = g_new0(struct iovec, p->page_count);
     return 0;
 }
 
@@ -214,6 +224,8 @@ static int nocomp_recv_setup(MultiFDRecvParams *p, Error **errp)
  */
 static void nocomp_recv_cleanup(MultiFDRecvParams *p)
 {
+    g_free(p->iov);
+    p->iov = NULL;
 }
 
 /**
@@ -734,8 +746,6 @@ static bool multifd_send_cleanup_channel(MultiFDSendParams *p, Error **errp)
     p->packet_len = 0;
     g_free(p->packet);
     p->packet = NULL;
-    g_free(p->iov);
-    p->iov = NULL;
     multifd_send_state->ops->send_cleanup(p, errp);
 
     return *errp == NULL;
@@ -1120,11 +1130,6 @@ bool multifd_send_setup(void)
             p->packet = g_malloc0(p->packet_len);
             p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
             p->packet->version = cpu_to_be32(MULTIFD_VERSION);
-
-            /* We need one extra place for the packet header */
-            p->iov = g_new0(struct iovec, page_count + 1);
-        } else {
-            p->iov = g_new0(struct iovec, page_count);
         }
         p->name = g_strdup_printf("multifdsend_%d", i);
         p->page_size = qemu_target_page_size();
@@ -1224,8 +1229,6 @@ static void multifd_recv_cleanup_channel(MultiFDRecvParams *p)
     p->packet_len = 0;
     g_free(p->packet);
     p->packet = NULL;
-    g_free(p->iov);
-    p->iov = NULL;
     g_free(p->normal);
     p->normal = NULL;
     g_free(p->zero);
@@ -1403,7 +1406,6 @@ int multifd_recv_setup(Error **errp)
             p->packet = g_malloc0(p->packet_len);
         }
         p->name = g_strdup_printf("multifdrecv_%d", i);
-        p->iov = g_new0(struct iovec, page_count);
         p->normal = g_new0(ram_addr_t, page_count);
         p->zero = g_new0(ram_addr_t, page_count);
         p->page_count = page_count;
-- 
2.33.0