From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52962) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ffoal-0003Hh-FU for qemu-devel@nongnu.org; Wed, 18 Jul 2018 11:42:18 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ffoag-0000IB-LD for qemu-devel@nongnu.org; Wed, 18 Jul 2018 11:42:15 -0400 Received: from relay.sw.ru ([185.231.240.75]:36386) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ffoag-0000FN-8h for qemu-devel@nongnu.org; Wed, 18 Jul 2018 11:42:10 -0400 From: Denis Plotnikov Date: Wed, 18 Jul 2018 18:41:51 +0300 Message-Id: <20180718154200.26777-9-dplotnikov@virtuozzo.com> In-Reply-To: <20180718154200.26777-1-dplotnikov@virtuozzo.com> References: <20180718154200.26777-1-dplotnikov@virtuozzo.com> Subject: [Qemu-devel] [PATCH v1 08/17] migration: add helpers to change VM memory protection rights List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: dgilbert@redhat.com, quintela@redhat.com, pbonzini@redhat.com Cc: qemu-devel@nongnu.org Signed-off-by: Denis Plotnikov --- migration/ram.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++ migration/ram.h | 3 +++ 2 files changed, 57 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index 27d3403435..ce3dead932 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1555,6 +1555,60 @@ void ram_block_list_destroy(void) } } +static int mem_protect(void *addr, uint64_t length, int prot) +{ + int ret = mprotect(addr, length, prot); + + if (ret < 0) { + error_report("%s: Can't change protection on ram block at %p", + __func__, addr); + } + + return ret; +} + +static int ram_set_ro(void *addr, uint64_t length) +{ + return mem_protect(addr, length, PROT_READ); +} + +static int ram_set_rw(void *addr, uint64_t length) +{ + return mem_protect(addr, length, PROT_READ | PROT_WRITE); +} + +int ram_block_list_set_readonly(void) +{ + RAMBlock *block = NULL; + RamBlockList *block_list = ram_bgs_block_list_get(); + int ret = 0; + + QLIST_FOREACH(block, block_list, bgs_next) { + ret = ram_set_ro(block->host, block->used_length); + if (ret) { + break; + } + } + + return ret; +} + +int ram_block_list_set_writable(void) +{ + RAMBlock *block = NULL; + RamBlockList *block_list = ram_bgs_block_list_get(); + int ret = 0; + + QLIST_FOREACH(block, block_list, bgs_next) { + ret = ram_set_rw(block->host, block->used_length); + if (ret) { + break; + } + } + + return ret; +} + static void ram_page_buffer_decrease_used(void) { qemu_event_reset(&ram_state->page_buffer.used_decreased); diff --git a/migration/ram.h b/migration/ram.h index 7c802c1d7f..4c463597a5 100644 --- a/migration/ram.h +++ b/migration/ram.h @@ -71,4 +71,7 @@ RAMBlock *ram_bgs_block_find(uint8_t *address, ram_addr_t *page_offset); void *ram_page_buffer_get(void); int ram_page_buffer_free(void *buffer); +int ram_block_list_set_readonly(void); +int ram_block_list_set_writable(void); + #endif -- 2.17.0