From patchwork Wed Jul 13 13:07:05 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: supriya kannery X-Patchwork-Id: 104501 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 A4272B6F6B for ; Wed, 13 Jul 2011 22:58:38 +1000 (EST) Received: from localhost ([::1]:42527 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qgz1O-0005L8-Ut for incoming@patchwork.ozlabs.org; Wed, 13 Jul 2011 08:58:35 -0400 Received: from eggs.gnu.org ([140.186.70.92]:59833) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qgyyj-0005Kg-Cw for qemu-devel@nongnu.org; Wed, 13 Jul 2011 08:55:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qgyyg-0005wF-1v for qemu-devel@nongnu.org; Wed, 13 Jul 2011 08:55:49 -0400 Received: from e28smtp08.in.ibm.com ([122.248.162.8]:44462) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qgyye-0005vg-K6 for qemu-devel@nongnu.org; Wed, 13 Jul 2011 08:55:45 -0400 Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by e28smtp08.in.ibm.com (8.14.4/8.13.1) with ESMTP id p6DCaxuE013493 for ; Wed, 13 Jul 2011 18:06:59 +0530 Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p6DCtCUb2568228 for ; Wed, 13 Jul 2011 18:25:12 +0530 Received: from d28av01.in.ibm.com (loopback [127.0.0.1]) by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p6DCtCG6009284 for ; Wed, 13 Jul 2011 18:25:12 +0530 Received: from [9.79.239.106] ([9.79.239.106]) by d28av01.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p6DCtBmE009233; Wed, 13 Jul 2011 18:25:11 +0530 Message-ID: <4E1D9879.8060009@in.ibm.com> Date: Wed, 13 Jul 2011 18:37:05 +0530 From: Supriya Kannery User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: Stefan Hajnoczi References: <20110704104237.28170.97021.sendpatchset@skannery> <20110704104320.28170.29248.sendpatchset@skannery> <4E12ED9A.7070805@in.ibm.com> In-Reply-To: <4E12ED9A.7070805@in.ibm.com> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 122.248.162.8 Cc: Kevin Wolf , qemu-devel@nongnu.org, Christoph Hellwig Subject: Re: [Qemu-devel] [V4 Patch 3/4 - Updated]Qemu: Command "block_set" for dynamic block params change 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 Updated "block_set" command to accept multiple -drive parameters. Also, added code for re-opening of device file with original flags, incase opening file using changed hostcache setting fails. ---------------------------------------------------------------------- New command "block_set" added for dynamically changing any of the block device parameters. For now, dynamic setting of hostcache params using this command is implemented. Other block device parameters, can be integrated in similar lines. Signed-off-by: Supriya Kannery --- block.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ block.h | 2 + blockdev.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ blockdev.h | 1 hmp-commands.hx | 14 +++++++++++++ qemu-config.c | 13 ++++++++++++ qemu-option.c | 25 +++++++++++++++++++++++ qemu-option.h | 2 + qmp-commands.hx | 28 ++++++++++++++++++++++++++ 9 files changed, 205 insertions(+) .params = "target", Index: qemu/block.c =================================================================== --- qemu.orig/block.c +++ qemu/block.c @@ -651,6 +651,40 @@ unlink_and_fail: return ret; } +int bdrv_reopen(BlockDriverState *bs, int bdrv_flags) +{ + BlockDriver *drv = bs->drv; + int ret = 0; + + /* Quiesce IO for the given block device */ + qemu_aio_flush(); + if (bdrv_flush(bs)) { + qerror_report(QERR_DATA_SYNC_FAILED, bs->device_name); + return ret; + } + bdrv_close(bs); + + + ret = bdrv_open(bs, bs->filename, bdrv_flags, drv); + if (ret < 0) { + /* Reopen failed. Try to open with original flags */ + error_report("Opening file with changed flags..."); + qerror_report(QERR_REOPEN_FILE_FAILED, bs->filename); + + ret = bdrv_open(bs, bs->filename, bs->open_flags, drv); + if (ret < 0) { + /* + * Reopen failed with orig and modified flags + */ + error_report("Opening file with original flags..."); + qerror_report(QERR_REOPEN_FILE_FAILED, bs->filename); + abort(); + } + } + + return ret; +} + void bdrv_close(BlockDriverState *bs) { if (bs->drv) { @@ -691,6 +725,32 @@ void bdrv_close_all(void) } } +int bdrv_change_hostcache(BlockDriverState *bs, bool enable_host_cache) +{ + int bdrv_flags = bs->open_flags; + + /* set hostcache flags (without changing WCE/flush bits) */ + if (enable_host_cache) { + bdrv_flags &= ~BDRV_O_NOCACHE; + } else { + bdrv_flags |= BDRV_O_NOCACHE; + } + + /* If no change in flags, no need to reopen */ + if (bdrv_flags == bs->open_flags) { + return 0; + } + + if (bdrv_is_inserted(bs)) { + /* Reopen file with changed set of flags */ + return bdrv_reopen(bs, bdrv_flags); + } else { + /* Save hostcache change for future use */ + bs->open_flags = bdrv_flags; + return 0; + } +} + /* make a BlockDriverState anonymous by removing from bdrv_state list. Also, NULL terminate the device_name to prevent double remove */ void bdrv_make_anon(BlockDriverState *bs) Index: qemu/block.h =================================================================== --- qemu.orig/block.h +++ qemu/block.h @@ -71,6 +71,7 @@ void bdrv_delete(BlockDriverState *bs); int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags); int bdrv_open(BlockDriverState *bs, const char *filename, int flags, BlockDriver *drv); +int bdrv_reopen(BlockDriverState *bs, int bdrv_flags); void bdrv_close(BlockDriverState *bs); int bdrv_attach(BlockDriverState *bs, DeviceState *qdev); void bdrv_detach(BlockDriverState *bs, DeviceState *qdev); @@ -96,6 +97,7 @@ void bdrv_commit_all(void); int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, const char *backing_fmt); void bdrv_register(BlockDriver *bdrv); +int bdrv_change_hostcache(BlockDriverState *bs, bool enable_host_cache); typedef struct BdrvCheckResult { Index: qemu/blockdev.c =================================================================== --- qemu.orig/blockdev.c +++ qemu/blockdev.c @@ -793,3 +793,63 @@ int do_block_resize(Monitor *mon, const return 0; } + + +/* + * Handle changes to block device settings, like hostcache, + * while guest is running. +*/ +int do_block_set(Monitor *mon, const QDict *qdict, QObject **ret_data) +{ + BlockDriverState *bs = NULL; + QemuOpts *opts; + int enable; + const char *device, *driver; + int ret; + + /* Validate device */ + device = qdict_get_str(qdict, "device"); + bs = bdrv_find(device); + if (!bs) { + qerror_report(QERR_DEVICE_NOT_FOUND, device); + return -1; + } + + opts = qemu_opts_from_qdict(qemu_find_opts("device"), qdict); + if (opts == NULL) { + return -1; + } + + /* If input not in "param=value" format, display error */ + driver = qemu_opt_get(opts, "driver"); + if (driver != NULL) { + error_report("Invalid parameter %s", driver); + return -1; + } + + /* Before validating parameters, remove "device" option */ + ret = qemu_opt_delete(opts, "device"); + if (ret == 1) { + error_report("Specify parameter to be changed"); + error_report("Usage: block_set device [prop=value][,...]"); + return 0; + } + + /* Validate parameters with "-drive" parameter list */ + ret = qemu_validate_opts(opts, "drive"); + if (ret == -1) { + return -1; + } + + /* Check for 'hostcache' parameter */ + enable = qemu_opt_get_bool(opts, "hostcache", -1); + if (enable != -1) { + return bdrv_change_hostcache(bs, enable); + } else { + error_report("Specify 'hostcache=on/off'"); + } + + return 0; + +} + Index: qemu/blockdev.h =================================================================== --- qemu.orig/blockdev.h +++ qemu/blockdev.h @@ -65,5 +65,6 @@ int do_change_block(Monitor *mon, const int do_drive_del(Monitor *mon, const QDict *qdict, QObject **ret_data); int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data); int do_block_resize(Monitor *mon, const QDict *qdict, QObject **ret_data); +int do_block_set(Monitor *mon, const QDict *qdict, QObject **ret_data); #endif Index: qemu/hmp-commands.hx =================================================================== --- qemu.orig/hmp-commands.hx +++ qemu/hmp-commands.hx @@ -70,6 +70,20 @@ but should be used with extreme caution. resizes image files, it can not resize block devices like LVM volumes. ETEXI + { + .name = "block_set", + .args_type = "device:B,device:O", + .params = "device [prop=value][,...]", + .help = "Change block device parameters [hostcache=on/off]", + .user_print = monitor_user_noop, + .mhandler.cmd_new = do_block_set, + }, +STEXI +@item block_set @var{config} +@findex block_set +Change block device parameters (eg: hostcache=on/off) while guest is running. +ETEXI + { .name = "eject", Index: qemu/qemu-config.c =================================================================== --- qemu.orig/qemu-config.c +++ qemu/qemu-config.c @@ -506,6 +506,19 @@ QemuOptsList *qemu_find_opts(const char return find_list(vm_config_groups, group); } +/* Validate given opts list with that of defined vm_group */ +int qemu_validate_opts(QemuOpts *opts, const char *group) +{ + QemuOptsList *vm_group; + + vm_group = qemu_find_opts(group); + if (vm_group == NULL) { + return -1; + } + + return qemu_opts_validate(opts, &vm_group->desc[0]); +} + void qemu_add_opts(QemuOptsList *list) { int entries, i; Index: qemu/qemu-option.c =================================================================== --- qemu.orig/qemu-option.c +++ qemu/qemu-option.c @@ -599,6 +599,31 @@ static void qemu_opt_del(QemuOpt *opt) qemu_free(opt); } +/* + * Delete specified parameter with name "name" from opts + * Return + * 0 - Deletion Successful + * -1 - Param doesn't exist in opts + * 1 - Deletion Successful and opts is empty. +*/ + +int qemu_opt_delete(QemuOpts *opts, const char *name) +{ + QemuOpt *opt = qemu_opt_find(opts, name); + if (opt == NULL) { + return -1; + } + + qemu_opt_del(opt); + + if ((&opts->head)->tqh_first == NULL) { + /* opt queue is empty */ + return 1; + } + + return 0; +} + int qemu_opt_set(QemuOpts *opts, const char *name, const char *value) { QemuOpt *opt; Index: qemu/qemu-option.h =================================================================== --- qemu.orig/qemu-option.h +++ qemu/qemu-option.h @@ -121,6 +121,7 @@ int qemu_opts_set(QemuOptsList *list, co const char *name, const char *value); const char *qemu_opts_id(QemuOpts *opts); void qemu_opts_del(QemuOpts *opts); +int qemu_opt_delete(QemuOpts *opts, const char *name); int qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc); int qemu_opts_do_parse(QemuOpts *opts, const char *params, const char *firstname); QemuOpts *qemu_opts_parse(QemuOptsList *list, const char *params, int permit_abbrev); @@ -131,5 +132,6 @@ typedef int (*qemu_opts_loopfunc)(QemuOp int qemu_opts_print(QemuOpts *opts, void *dummy); int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque, int abort_on_failure); +int qemu_validate_opts(QemuOpts *opts, const char *id); #endif Index: qemu/qmp-commands.hx =================================================================== --- qemu.orig/qmp-commands.hx +++ qemu/qmp-commands.hx @@ -693,7 +693,35 @@ Example: EQMP + { + .name = "block_set", + .args_type = "device:B,device:O", + .params = "device [prop=value][,...]", + .help = "Change block device parameters [hostcache=on/off]", + .user_print = monitor_user_noop, + .mhandler.cmd_new = do_block_set, + }, + +SQMP +block_set +--------- + +Change various block device parameters (eg: hostcache=on/off) + +Arguments: + +- "device": the device's ID, must be unique (json-string) +- device parameters to be changed (eg: "hostcache": "off") + +Example: + +-> { "execute": "block_set", "arguments": { "device": "ide0-hd0", "hostcache": "off"} } +<- { "return": {} } + +EQMP + + { .name = "balloon", .args_type = "value:M",