From patchwork Wed Jan 4 14:08:57 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 134256 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2CB4E1007D6 for ; Thu, 5 Jan 2012 01:12:11 +1100 (EST) Received: from localhost ([::1]:56202 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RiRZX-0000SP-Gu for incoming@patchwork.ozlabs.org; Wed, 04 Jan 2012 09:12:07 -0500 Received: from eggs.gnu.org ([140.186.70.92]:45823) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RiRZJ-0000Rk-8l for qemu-devel@nongnu.org; Wed, 04 Jan 2012 09:11:58 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RiRZC-0001cV-Qr for qemu-devel@nongnu.org; Wed, 04 Jan 2012 09:11:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:23787) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RiRZC-0001cK-Gh for qemu-devel@nongnu.org; Wed, 04 Jan 2012 09:11:46 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q04EBihZ026663 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 4 Jan 2012 09:11:44 -0500 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q04EBhfR018356; Wed, 4 Jan 2012 09:11:44 -0500 Received: from amt.cnet (vpn-9-110.rdu.redhat.com [10.11.9.110]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id q04EBggN019654; Wed, 4 Jan 2012 09:11:42 -0500 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 3BE71652354; Wed, 4 Jan 2012 12:10:55 -0200 (BRST) Received: (from marcelo@localhost) by amt.cnet (8.14.5/8.14.5/Submit) id q04EArN4019587; Wed, 4 Jan 2012 12:10:53 -0200 Message-Id: <20120104140945.618799948@redhat.com> User-Agent: quilt/0.48-1 Date: Wed, 04 Jan 2012 12:08:57 -0200 From: Marcelo Tosatti To: stefanha@linux.vnet.ibm.com, kwolf@redhat.com, qemu-devel@nongnu.org References: <20120104140854.631720304@redhat.com> Content-Disposition: inline; filename=block-stream-base X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 209.132.183.28 Cc: Marcelo Tosatti Subject: [Qemu-devel] [patch 3/4] block stream: add support for partial streaming X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Add support for streaming data from an intermediate section of the image chain (see patch and documentation for details). Signed-off-by: Marcelo Tosatti Index: stefanha/block.c =================================================================== --- stefanha.orig/block.c +++ stefanha/block.c @@ -2229,6 +2229,70 @@ int bdrv_is_allocated(BlockDriverState * return data.ret; } +/* + * Given an image chain: [BASE] -> [INTER1] -> [INTER2] -> [TOP] + * + * Return true if the given sector is allocated in top or base. + * Return false if the given sector is allocated in intermediate images. + * + * 'pnum' is set to the number of sectors (including and immediately following + * the specified sector) that are known to be in the same + * allocated/unallocated state. + * + */ +int coroutine_fn bdrv_co_is_allocated_base(BlockDriverState *top, + BlockDriverState *base, + int64_t sector_num, + int nb_sectors, int *pnum) +{ + BlockDriverState *intermediate; + int ret, n; + + ret = bdrv_co_is_allocated(top, sector_num, nb_sectors, &n); + if (ret) { + *pnum = n; + return ret; + } + + /* + * Is the unallocated chunk [sector_num, n] also + * unallocated between base and top? + */ + intermediate = top->backing_hd; + + while (intermediate) { + int pnum_inter; + + /* reached base */ + if (intermediate == base) { + *pnum = n; + return 1; + } + ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors, + &pnum_inter); + if (ret < 0) { + return ret; + } else if (ret) { + *pnum = pnum_inter; + return 0; + } + + /* + * [sector_num, nb_sectors] is unallocated on top but intermediate + * might have + * + * [sector_num+x, nr_sectors] allocated. + */ + if (n > pnum_inter) { + n = pnum_inter; + } + + intermediate = intermediate->backing_hd; + } + + return 1; +} + void bdrv_mon_event(const BlockDriverState *bdrv, BlockMonEventAction action, int is_read) { Index: stefanha/block.h =================================================================== --- stefanha.orig/block.h +++ stefanha/block.h @@ -222,6 +222,10 @@ int bdrv_co_discard(BlockDriverState *bs int bdrv_has_zero_init(BlockDriverState *bs); int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum); +int coroutine_fn bdrv_co_is_allocated_base(BlockDriverState *top, + BlockDriverState *base, + int64_t sector_num, int nb_sectors, + int *pnum); #define BIOS_ATA_TRANSLATION_AUTO 0 #define BIOS_ATA_TRANSLATION_NONE 1 Index: stefanha/block/stream.c =================================================================== --- stefanha.orig/block/stream.c +++ stefanha/block/stream.c @@ -57,6 +57,7 @@ typedef struct StreamBlockJob { BlockJob common; RateLimit limit; BlockDriverState *base; + char backing_file_id[1024]; } StreamBlockJob; static int coroutine_fn stream_populate(BlockDriverState *bs, @@ -79,6 +80,7 @@ static void coroutine_fn stream_run(void { StreamBlockJob *s = opaque; BlockDriverState *bs = s->common.bs; + BlockDriverState *base = s->base; int64_t sector_num, end; int ret = 0; int n; @@ -97,8 +99,17 @@ retry: break; } - ret = bdrv_co_is_allocated(bs, sector_num, - STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, &n); + + if (base) { + ret = bdrv_co_is_allocated_base(bs, base, sector_num, + STREAM_BUFFER_SIZE / + BDRV_SECTOR_SIZE, + &n); + } else { + ret = bdrv_co_is_allocated(bs, sector_num, + STREAM_BUFFER_SIZE / BDRV_SECTOR_SIZE, + &n); + } trace_stream_one_iteration(s, sector_num, n, ret); if (ret == 0) { if (s->common.speed) { @@ -115,6 +126,7 @@ retry: if (ret < 0) { break; } + ret = 0; /* Publish progress */ s->common.offset += n * BDRV_SECTOR_SIZE; @@ -129,7 +141,10 @@ retry: bdrv_disable_zero_detection(bs); if (sector_num == end && ret == 0) { - bdrv_change_backing_file(bs, NULL, NULL); + const char *base_id = NULL; + if (base) + base_id = s->backing_file_id; + bdrv_change_backing_file(bs, base_id, NULL); } qemu_vfree(buf); @@ -155,7 +170,8 @@ static BlockJobType stream_job_type = { }; int stream_start(BlockDriverState *bs, BlockDriverState *base, - BlockDriverCompletionFunc *cb, void *opaque) + const char *base_id, BlockDriverCompletionFunc *cb, + void *opaque) { StreamBlockJob *s; Coroutine *co; @@ -166,6 +182,8 @@ int stream_start(BlockDriverState *bs, B s = block_job_create(&stream_job_type, bs, cb, opaque); s->base = base; + if (base_id) + pstrcpy(s->backing_file_id, sizeof(s->backing_file_id), base_id); co = qemu_coroutine_create(stream_run); trace_stream_start(bs, base, s, co, opaque); Index: stefanha/blockdev.c =================================================================== --- stefanha.orig/blockdev.c +++ stefanha/blockdev.c @@ -931,6 +931,7 @@ void qmp_block_stream(const char *device const char *base, Error **errp) { BlockDriverState *bs; + BlockDriverState *base_bs = NULL; int ret; bs = bdrv_find(device); @@ -939,13 +940,15 @@ void qmp_block_stream(const char *device return; } - /* Base device not supported */ if (base) { - error_set(errp, QERR_NOT_SUPPORTED); - return; + base_bs = bdrv_find_backing_image(bs, base); + if (base_bs == NULL) { + error_set(errp, QERR_BASE_ID_NOT_FOUND, base); + return; + } } - ret = stream_start(bs, NULL, block_stream_cb, bs); + ret = stream_start(bs, base_bs, base, block_stream_cb, bs); if (ret < 0) { switch (ret) { case -EBUSY: Index: stefanha/block_int.h =================================================================== --- stefanha.orig/block_int.h +++ stefanha/block_int.h @@ -380,6 +380,7 @@ static inline bool block_job_is_cancelle } int stream_start(BlockDriverState *bs, BlockDriverState *base, - BlockDriverCompletionFunc *cb, void *opaque); + const char *base_id, BlockDriverCompletionFunc *cb, + void *opaque); #endif /* BLOCK_INT_H */