From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:37877) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SfdSD-00070P-2F for qemu-devel@nongnu.org; Fri, 15 Jun 2012 16:49:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SfdSB-0001Ru-3I for qemu-devel@nongnu.org; Fri, 15 Jun 2012 16:49:12 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:60331) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SfdSA-0001RJ-V2 for qemu-devel@nongnu.org; Fri, 15 Jun 2012 16:49:11 -0400 Received: from /spool/local by e7.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 15 Jun 2012 16:49:07 -0400 Received: from d01relay01.pok.ibm.com (d01relay01.pok.ibm.com [9.56.227.233]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id BBCDE38C8052 for ; Fri, 15 Jun 2012 16:49:03 -0400 (EDT) Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay01.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q5FKn3qo163156 for ; Fri, 15 Jun 2012 16:49:03 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q5FKn2eQ007820 for ; Fri, 15 Jun 2012 17:49:03 -0300 From: Supriya Kannery Date: Sat, 16 Jun 2012 02:18:58 +0530 Message-Id: <20120615204858.9853.80223.sendpatchset@skannery.in.ibm.com> In-Reply-To: <20120615204648.9853.1225.sendpatchset@skannery.in.ibm.com> References: <20120615204648.9853.1225.sendpatchset@skannery.in.ibm.com> Subject: [Qemu-devel] [v1 Patch 9/10]Qemu: qcow image file reopen List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Shrinidhi Joshi , Stefan Hajnoczi , Jeff Cody , Luiz Capitulino , Christoph Hellwig qcow driver changes for bdrv_reopen_xx functions to safely reopen image files. Reopening of image files while changing hostcache dynamically is handled here. Signed-off-by: Shrinidhi Joshi Index: qemu/block/qcow.c =================================================================== --- qemu.orig/block/qcow.c +++ qemu/block/qcow.c @@ -78,7 +78,14 @@ typedef struct BDRVQcowState { Error *migration_blocker; } BDRVQcowState; +typedef struct BDRVQcowReopenState { + BDRVReopenState reopen_state; + BDRVQcowState *stash_s; +} BDRVQcowReopenState; + static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset); +static void qcow_stash_state(BDRVQcowState *stash_s, BDRVQcowState *s); +static void qcow_revert_state(BDRVQcowState *s, BDRVQcowState *stash_s); static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) { @@ -197,6 +204,103 @@ static int qcow_open(BlockDriverState *b return ret; } +static int qcow_reopen_prepare(BlockDriverState *bs, BDRVReopenState **prs, + int flags) +{ + BDRVQcowReopenState *qcow_rs = g_malloc0(sizeof(BDRVQcowReopenState)); + int ret = 0; + BDRVQcowState *s = bs->opaque; + + qcow_rs->reopen_state.bs = bs; + qcow_rs->stash_s = g_malloc0(sizeof(BDRVQcowState)); + qcow_stash_state(qcow_rs->stash_s, s); + *prs = &(qcow_rs->reopen_state); + + ret = qcow_open(bs, flags); + return ret; +} + +static void qcow_reopen_commit(BlockDriverState *bs, BDRVReopenState *rs) +{ + BDRVQcowReopenState *qcow_rs; + + qcow_rs = container_of(rs, BDRVQcowReopenState, reopen_state); + g_free(qcow_rs->stash_s); + g_free(qcow_rs); +} + +static void qcow_reopen_abort(BlockDriverState *bs, BDRVReopenState *rs) +{ + BDRVQcowReopenState *qcow_rs; + BDRVQcowState *s = bs->opaque; + + qcow_rs = container_of(rs, BDRVQcowReopenState, reopen_state); + + /* revert to stashed state */ + qcow_revert_state(s, qcow_rs->stash_s); + + g_free(qcow_rs->stash_s); + g_free(qcow_rs); +} + +static void qcow_stash_state(BDRVQcowState *stash_s, BDRVQcowState *s) +{ + int i; + + stash_s->cluster_bits = s->cluster_bits; + stash_s->cluster_size = s->cluster_size; + stash_s->cluster_sectors = s->cluster_sectors; + stash_s->l2_bits = s->l2_bits; + stash_s->l2_size = s->l2_size; + stash_s->l1_size = s->l1_size; + stash_s->cluster_offset_mask = s->cluster_offset_mask; + stash_s->l1_table_offset = s->l1_table_offset; + stash_s->l1_table = s->l1_table; + stash_s->l2_cache = s->l2_cache; + for (i = 0; i < L2_CACHE_SIZE; i++) { + stash_s->l2_cache_offsets[i] = s->l2_cache_offsets[i]; + stash_s->l2_cache_counts[i] = s->l2_cache_counts[i]; + } + stash_s->cluster_cache = s->cluster_cache; + stash_s->cluster_data = s->cluster_data; + stash_s->cluster_cache_offset = s->cluster_cache_offset; + stash_s->crypt_method = s->crypt_method; + stash_s->crypt_method_header = s->crypt_method_header; + stash_s->aes_encrypt_key = s->aes_encrypt_key; + stash_s->aes_decrypt_key = s->aes_decrypt_key; + stash_s->lock = s->lock; + stash_s->migration_blocker = s->migration_blocker; +} + +static void qcow_revert_state(BDRVQcowState *s, BDRVQcowState *stash_s) +{ + int i; + + s->cluster_bits = stash_s->cluster_bits; + s->cluster_size = stash_s->cluster_size; + s->cluster_sectors = stash_s->cluster_sectors; + s->l2_bits = stash_s->l2_bits; + s->l2_size = stash_s->l2_size; + s->l1_size = stash_s->l1_size; + s->cluster_offset_mask = stash_s->cluster_offset_mask; + s->l1_table_offset = stash_s->l1_table_offset; + s->l1_table = stash_s->l1_table; + s->l2_cache = stash_s->l2_cache; + for (i = 0; i < L2_CACHE_SIZE; i++) { + s->l2_cache_offsets[i] = s->l2_cache_offsets[i]; + s->l2_cache_counts[i] = stash_s->l2_cache_counts[i]; + } + s->cluster_cache = stash_s->cluster_cache; + s->cluster_data = stash_s->cluster_data; + s->cluster_cache_offset = stash_s->cluster_cache_offset; + s->crypt_method = stash_s->crypt_method; + s->crypt_method_header = stash_s->crypt_method_header; + s->aes_encrypt_key = stash_s->aes_encrypt_key; + s->aes_decrypt_key = stash_s->aes_decrypt_key; + s->lock = stash_s->lock; + s->migration_blocker = stash_s->migration_blocker; +} + static int qcow_set_key(BlockDriverState *bs, const char *key) { BDRVQcowState *s = bs->opaque; @@ -870,6 +974,10 @@ static BlockDriver bdrv_qcow = { .bdrv_close = qcow_close, .bdrv_create = qcow_create, + .bdrv_reopen_prepare = qcow_reopen_prepare, + .bdrv_reopen_commit = qcow_reopen_commit, + .bdrv_reopen_abort = qcow_reopen_abort, + .bdrv_co_readv = qcow_co_readv, .bdrv_co_writev = qcow_co_writev, .bdrv_co_is_allocated = qcow_co_is_allocated,