From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52986) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XBfvK-0005RP-5E for qemu-devel@nongnu.org; Mon, 28 Jul 2014 04:04:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XBfvA-00059N-6Y for qemu-devel@nongnu.org; Mon, 28 Jul 2014 04:04:46 -0400 From: Igor Mammedov Date: Mon, 28 Jul 2014 08:03:24 +0000 Message-Id: <1406534605-18911-2-git-send-email-imammedo@redhat.com> In-Reply-To: <1406534605-18911-1-git-send-email-imammedo@redhat.com> References: <1406534605-18911-1-git-send-email-imammedo@redhat.com> Subject: [Qemu-devel] [PATCH for-2.1 v2 1/2] migration: load smaller RAMBlock to a bigger one if permitted List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: peter.maydell@linaro.org, mst@redhat.com, dgilbert@redhat.com, qemu-stable@nongnu.org, amit.shah@redhat.com, pbonzini@redhat.com, lersek@redhat.com Add API to mark memory region as extend-able on migration, to allow migration code to load smaller RAMBlock into a bigger one on destination QEMU instance. This will allow to fix broken migration from QEMU 1.7/2.0 to QEMU 2.1 due to ACPI tables size changes across 1.7/2.0/2.1 versions by marking ACPI tables ROM blob as extend-able. So that smaller tables from previous version could be always migrated to a bigger rom blob on new version. Credits-for-idea: Michael S. Tsirkin Signed-off-by: Igor Mammedov --- v2: fixed patch as suggested by Laszlo --- arch_init.c | 22 +++++++++++++++++----- exec.c | 8 ++++++++ include/exec/memory.h | 11 +++++++++++ include/exec/ram_addr.h | 3 +++ memory.c | 5 +++++ 5 files changed, 44 insertions(+), 5 deletions(-) diff --git a/arch_init.c b/arch_init.c index 8ddaf35..2c0c238 100644 --- a/arch_init.c +++ b/arch_init.c @@ -1071,11 +1071,23 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) QTAILQ_FOREACH(block, &ram_list.blocks, next) { if (!strncmp(id, block->idstr, sizeof(id))) { - if (block->length != length) { - error_report("Length mismatch: %s: " RAM_ADDR_FMT - " in != " RAM_ADDR_FMT, id, length, - block->length); - ret = -EINVAL; + if (block->flags & RAM_EXTENDABLE_ON_MIGRATE) { + if (block->length < length) { + error_report("Length too big: %s: " RAM_ADDR_FMT + " in > " RAM_ADDR_FMT, id, length, + block->length); + ret = -EINVAL; + } else { + memset(block->host, 0, block->length); + } + } else { + if (block->length != length) { + error_report("Length mismatch: %s: " + RAM_ADDR_FMT " in != " + RAM_ADDR_FMT, + id, length, block->length); + ret = -EINVAL; + } } break; } diff --git a/exec.c b/exec.c index 765bd94..02536f8e 100644 --- a/exec.c +++ b/exec.c @@ -1214,6 +1214,14 @@ void qemu_ram_unset_idstr(ram_addr_t addr) } } +void qemu_ram_set_extendable_on_migration(ram_addr_t addr) +{ + RAMBlock *block = find_ram_block(addr); + + assert(block != NULL); + block->flags |= RAM_EXTENDABLE_ON_MIGRATE; +} + static int memory_try_enable_merging(void *addr, size_t len) { if (!qemu_opt_get_bool(qemu_get_machine_opts(), "mem-merge", true)) { diff --git a/include/exec/memory.h b/include/exec/memory.h index e2c8e3e..f96ddbb 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -894,6 +894,17 @@ bool memory_region_present(MemoryRegion *container, hwaddr addr); bool memory_region_is_mapped(MemoryRegion *mr); /** + * memory_region_permit_extendable_migration: marks #MemoryRegion + * as extendable on migration, allowing the migration code to load + * source memory block of smaller size than destination memory block + * at migration time + * + * @mr: a #MemoryRegion whose #RAMBlock should be marked as + * extendable on migration + */ +void memory_region_permit_extendable_migration(MemoryRegion *mr); + +/** * memory_region_find: translate an address/size relative to a * MemoryRegion into a #MemoryRegionSection. * diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index 6593be1..7a6b782 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -34,6 +34,9 @@ void *qemu_get_ram_ptr(ram_addr_t addr); void qemu_ram_free(ram_addr_t addr); void qemu_ram_free_from_ptr(ram_addr_t addr); +#define RAM_EXTENDABLE_ON_MIGRATE (1U << 31) +void qemu_ram_set_extendable_on_migration(ram_addr_t addr); + static inline bool cpu_physical_memory_get_dirty(ram_addr_t start, ram_addr_t length, unsigned client) diff --git a/memory.c b/memory.c index 64d7176..744c746 100644 --- a/memory.c +++ b/memory.c @@ -1791,6 +1791,11 @@ bool memory_region_is_mapped(MemoryRegion *mr) return mr->container ? true : false; } +void memory_region_permit_extendable_migration(MemoryRegion *mr) +{ + qemu_ram_set_extendable_on_migration(mr->ram_addr); +} + MemoryRegionSection memory_region_find(MemoryRegion *mr, hwaddr addr, uint64_t size) { -- 1.8.3.1