Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Thu 31 Aug 2017 09:21:49 BST
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  qcow2: allocate cluster_cache/cluster_data on demand
  qemu-doc: Add UUID support in initiator name
  tests: migration/guestperf Python 2.6 argparse compatibility
  docker.py: Python 2.6 argparse compatibility
  scripts: add argparse module for Python 2.6 compatibility
  misc: Remove unused Error variables
  oslib-posix: Print errors before aborting on qemu_alloc_stack()
  throttle: Test the valid range of config values
  throttle: Make burst_length 64bit and add range checks
  throttle: Make LeakyBucket.avg and LeakyBucket.max integer types
  throttle: Remove throttle_fix_bucket() / throttle_unfix_bucket()
  throttle: Make throttle_is_valid() a bit less verbose
  throttle: Update the throttle_fix_bucket() documentation
  throttle: Fix wrong variable name in the header documentation
  nvme: Fix get/set number of queues feature, again
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

COPYING.PYTHON

+A. HISTORY OF THE SOFTWARE
+==========================
+
+Python was created in the early 1990s by Guido van Rossum at Stichting
+Mathematisch Centrum (CWI, see http://www.cwi.nl) in the Netherlands
+as a successor of a language called ABC.  Guido remains Python's
+principal author, although it includes many contributions from others.
+
+In 1995, Guido continued his work on Python at the Corporation for
+National Research Initiatives (CNRI, see http://www.cnri.reston.va.us)
+in Reston, Virginia where he released several versions of the
+software.
+
+In May 2000, Guido and the Python core development team moved to
+BeOpen.com to form the BeOpen PythonLabs team.  In October of the same
+year, the PythonLabs team moved to Digital Creations (now Zope
+Corporation, see http://www.zope.com).  In 2001, the Python Software
+Foundation (PSF, see http://www.python.org/psf/) was formed, a
+non-profit organization created specifically to own Python-related
+Intellectual Property.  Zope Corporation is a sponsoring member of
+the PSF.
+
+All Python releases are Open Source (see http://www.opensource.org for
+the Open Source Definition).  Historically, most, but not all, Python
+releases have also been GPL-compatible; the table below summarizes
+the various releases.
+
+    Release         Derived     Year        Owner       GPL-
+                    from                                compatible? (1)
+
+    0.9.0 thru 1.2              1991-1995   CWI         yes
+    1.3 thru 1.5.2  1.2         1995-1999   CNRI        yes
+    1.6             1.5.2       2000        CNRI        no
+    2.0             1.6         2000        BeOpen.com  no
+    1.6.1           1.6         2001        CNRI        yes (2)
+    2.1             2.0+1.6.1   2001        PSF         no
+    2.0.1           2.0+1.6.1   2001        PSF         yes
+    2.1.1           2.1+2.0.1   2001        PSF         yes
+    2.2             2.1.1       2001        PSF         yes
+    2.1.2           2.1.1       2002        PSF         yes
+    2.1.3           2.1.2       2002        PSF         yes
+    2.2.1           2.2         2002        PSF         yes
+    2.2.2           2.2.1       2002        PSF         yes
+    2.2.3           2.2.2       2003        PSF         yes
+    2.3             2.2.2       2002-2003   PSF         yes
+    2.3.1           2.3         2002-2003   PSF         yes
+    2.3.2           2.3.1       2002-2003   PSF         yes
+    2.3.3           2.3.2       2002-2003   PSF         yes
+    2.3.4           2.3.3       2004        PSF         yes
+    2.3.5           2.3.4       2005        PSF         yes
+    2.4             2.3         2004        PSF         yes
+    2.4.1           2.4         2005        PSF         yes
+    2.4.2           2.4.1       2005        PSF         yes
+    2.4.3           2.4.2       2006        PSF         yes
+    2.5             2.4         2006        PSF         yes
+    2.7             2.6         2010        PSF         yes
+
+Footnotes:
+
+(1) GPL-compatible doesn't mean that we're distributing Python under
+    the GPL.  All Python licenses, unlike the GPL, let you distribute
+    a modified version without making your changes open source.  The
+    GPL-compatible licenses make it possible to combine Python with
+    other software that is released under the GPL; the others don't.
+
+(2) According to Richard Stallman, 1.6.1 is not GPL-compatible,
+    because its license has a choice of law clause.  According to
+    CNRI, however, Stallman's lawyer has told CNRI's lawyer that 1.6.1
+    is "not incompatible" with the GPL.
+
+Thanks to the many outside volunteers who have worked under Guido's
+direction to make these releases possible.
+
+
+B. TERMS AND CONDITIONS FOR ACCESSING OR OTHERWISE USING PYTHON
+===============================================================
+
+PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
+--------------------------------------------
+
+1. This LICENSE AGREEMENT is between the Python Software Foundation
+("PSF"), and the Individual or Organization ("Licensee") accessing and
+otherwise using this software ("Python") in source or binary form and
+its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, PSF
+hereby grants Licensee a nonexclusive, royalty-free, world-wide
+license to reproduce, analyze, test, perform and/or display publicly,
+prepare derivative works, distribute, and otherwise use Python
+alone or in any derivative version, provided, however, that PSF's
+License Agreement and PSF's notice of copyright, i.e., "Copyright (c)
+2001, 2002, 2003, 2004, 2005, 2006 Python Software Foundation; All Rights
+Reserved" are retained in Python alone or in any derivative version 
+prepared by Licensee.
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python.
+
+4. PSF is making Python available to Licensee on an "AS IS"
+basis.  PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. Nothing in this License Agreement shall be deemed to create any
+relationship of agency, partnership, or joint venture between PSF and
+Licensee.  This License Agreement does not grant permission to use PSF
+trademarks or trade name in a trademark sense to endorse or promote
+products or services of Licensee, or any third party.
+
+8. By copying, installing or otherwise using Python, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+BEOPEN.COM LICENSE AGREEMENT FOR PYTHON 2.0
+-------------------------------------------
+
+BEOPEN PYTHON OPEN SOURCE LICENSE AGREEMENT VERSION 1
+
+1. This LICENSE AGREEMENT is between BeOpen.com ("BeOpen"), having an
+office at 160 Saratoga Avenue, Santa Clara, CA 95051, and the
+Individual or Organization ("Licensee") accessing and otherwise using
+this software in source or binary form and its associated
+documentation ("the Software").
+
+2. Subject to the terms and conditions of this BeOpen Python License
+Agreement, BeOpen hereby grants Licensee a non-exclusive,
+royalty-free, world-wide license to reproduce, analyze, test, perform
+and/or display publicly, prepare derivative works, distribute, and
+otherwise use the Software alone or in any derivative version,
+provided, however, that the BeOpen Python License is retained in the
+Software, alone or in any derivative version prepared by Licensee.
+
+3. BeOpen is making the Software available to Licensee on an "AS IS"
+basis.  BEOPEN MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, BEOPEN MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF THE SOFTWARE WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+4. BEOPEN SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF THE
+SOFTWARE FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS
+AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THE SOFTWARE, OR ANY
+DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+5. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+6. This License Agreement shall be governed by and interpreted in all
+respects by the law of the State of California, excluding conflict of
+law provisions.  Nothing in this License Agreement shall be deemed to
+create any relationship of agency, partnership, or joint venture
+between BeOpen and Licensee.  This License Agreement does not grant
+permission to use BeOpen trademarks or trade names in a trademark
+sense to endorse or promote products or services of Licensee, or any
+third party.  As an exception, the "BeOpen Python" logos available at
+http://www.pythonlabs.com/logos.html may be used according to the
+permissions granted on that web page.
+
+7. By copying, installing or otherwise using the software, Licensee
+agrees to be bound by the terms and conditions of this License
+Agreement.
+
+
+CNRI LICENSE AGREEMENT FOR PYTHON 1.6.1
+---------------------------------------
+
+1. This LICENSE AGREEMENT is between the Corporation for National
+Research Initiatives, having an office at 1895 Preston White Drive,
+Reston, VA 20191 ("CNRI"), and the Individual or Organization
+("Licensee") accessing and otherwise using Python 1.6.1 software in
+source or binary form and its associated documentation.
+
+2. Subject to the terms and conditions of this License Agreement, CNRI
+hereby grants Licensee a nonexclusive, royalty-free, world-wide
+license to reproduce, analyze, test, perform and/or display publicly,
+prepare derivative works, distribute, and otherwise use Python 1.6.1
+alone or in any derivative version, provided, however, that CNRI's
+License Agreement and CNRI's notice of copyright, i.e., "Copyright (c)
+1995-2001 Corporation for National Research Initiatives; All Rights
+Reserved" are retained in Python 1.6.1 alone or in any derivative
+version prepared by Licensee.  Alternately, in lieu of CNRI's License
+Agreement, Licensee may substitute the following text (omitting the
+quotes): "Python 1.6.1 is made available subject to the terms and
+conditions in CNRI's License Agreement.  This Agreement together with
+Python 1.6.1 may be located on the Internet using the following
+unique, persistent identifier (known as a handle): 1895.22/1013.  This
+Agreement may also be obtained from a proxy server on the Internet
+using the following URL: http://hdl.handle.net/1895.22/1013".
+
+3. In the event Licensee prepares a derivative work that is based on
+or incorporates Python 1.6.1 or any part thereof, and wants to make
+the derivative work available to others as provided herein, then
+Licensee hereby agrees to include in any such work a brief summary of
+the changes made to Python 1.6.1.
+
+4. CNRI is making Python 1.6.1 available to Licensee on an "AS IS"
+basis.  CNRI MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
+IMPLIED.  BY WAY OF EXAMPLE, BUT NOT LIMITATION, CNRI MAKES NO AND
+DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
+FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON 1.6.1 WILL NOT
+INFRINGE ANY THIRD PARTY RIGHTS.
+
+5. CNRI SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
+1.6.1 FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
+A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 1.6.1,
+OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
+
+6. This License Agreement will automatically terminate upon a material
+breach of its terms and conditions.
+
+7. This License Agreement shall be governed by the federal
+intellectual property law of the United States, including without
+limitation the federal copyright law, and, to the extent such
+U.S. federal law does not apply, by the law of the Commonwealth of
+Virginia, excluding Virginia's conflict of law provisions.
+Notwithstanding the foregoing, with regard to derivative works based
+on Python 1.6.1 that incorporate non-separable material that was
+previously distributed under the GNU General Public License (GPL), the
+law of the Commonwealth of Virginia shall govern this License
+Agreement only as to issues arising under or with respect to
+Paragraphs 4, 5, and 7 of this License Agreement.  Nothing in this
+License Agreement shall be deemed to create any relationship of
+agency, partnership, or joint venture between CNRI and Licensee.  This
+License Agreement does not grant permission to use CNRI trademarks or
+trade name in a trademark sense to endorse or promote products or
+services of Licensee, or any third party.
+
+8. By clicking on the "ACCEPT" button where indicated, or by copying,
+installing or otherwise using Python 1.6.1, Licensee agrees to be
+bound by the terms and conditions of this License Agreement.
+
+        ACCEPT
+
+
+CWI LICENSE AGREEMENT FOR PYTHON 0.9.0 THROUGH 1.2
+--------------------------------------------------
+
+Copyright (c) 1991 - 1995, Stichting Mathematisch Centrum Amsterdam,
+The Netherlands.  All rights reserved.
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior
+permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

block/qcow.c

@@ -454,13 +454,11 @@ static uint64_t get_cluster_offset(BlockDriverState *bs,
                     start_sect = (offset & ~(s->cluster_size - 1)) >> 9;
                     for(i = 0; i < s->cluster_sectors; i++) {
                         if (i < n_start || i >= n_end) {
-                            Error *err = NULL;
                             memset(s->cluster_data, 0x00, 512);
                             if (qcrypto_block_encrypt(s->crypto, start_sect + i,
                                                       s->cluster_data,
                                                       BDRV_SECTOR_SIZE,
-                                                      &err) < 0) {
-                                error_free(err);
+                                                      NULL) < 0) {
                                 errno = EIO;
                                 return -1;
                             }
@@ -572,7 +570,6 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
     QEMUIOVector hd_qiov;
     uint8_t *buf;
     void *orig_buf;
-    Error *err = NULL;
 
     if (qiov->niov > 1) {
         buf = orig_buf = qemu_try_blockalign(bs, qiov->size);
@@ -637,7 +634,7 @@ static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
             if (bs->encrypted) {
                 assert(s->crypto);
                 if (qcrypto_block_decrypt(s->crypto, sector_num, buf,
-                                          n * BDRV_SECTOR_SIZE, &err) < 0) {
+                                          n * BDRV_SECTOR_SIZE, NULL) < 0) {
                     goto fail;
                 }
             }
@@ -660,7 +657,6 @@ done:
     return ret;
 
 fail:
-    error_free(err);
     ret = -EIO;
     goto done;
 }
@@ -709,11 +705,9 @@ static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
             break;
         }
         if (bs->encrypted) {
-            Error *err = NULL;
             assert(s->crypto);
             if (qcrypto_block_encrypt(s->crypto, sector_num, buf,
-                                      n * BDRV_SECTOR_SIZE, &err) < 0) {
-                error_free(err);
+                                      n * BDRV_SECTOR_SIZE, NULL) < 0) {
                 ret = -EIO;
                 break;
             }

block/qcow2-cluster.c

@@ -1516,6 +1516,23 @@ int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
         nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
         sector_offset = coffset & 511;
         csize = nb_csectors * 512 - sector_offset;
+
+        /* Allocate buffers on first decompress operation, most images are
+         * uncompressed and the memory overhead can be avoided.  The buffers
+         * are freed in .bdrv_close().
+         */
+        if (!s->cluster_data) {
+            /* one more sector for decompressed data alignment */
+            s->cluster_data = qemu_try_blockalign(bs->file->bs,
+                    QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size + 512);
+            if (!s->cluster_data) {
+                return -ENOMEM;
+            }
+        }
+        if (!s->cluster_cache) {
+            s->cluster_cache = g_malloc(s->cluster_size);
+        }
+
         BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED);
         ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data,
                         nb_csectors);

block/qcow2.c

@@ -1360,16 +1360,6 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
         goto fail;
     }
 
-    s->cluster_cache = g_malloc(s->cluster_size);
-    /* one more sector for decompressed data alignment */
-    s->cluster_data = qemu_try_blockalign(bs->file->bs, QCOW_MAX_CRYPT_CLUSTERS
-                                                    * s->cluster_size + 512);
-    if (s->cluster_data == NULL) {
-        error_setg(errp, "Could not allocate temporary cluster buffer");
-        ret = -ENOMEM;
-        goto fail;
-    }
-
     s->cluster_cache_offset = -1;
     s->flags = flags;
 
@@ -1507,8 +1497,6 @@ static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
     if (s->refcount_block_cache) {
         qcow2_cache_destroy(bs, s->refcount_block_cache);
     }
-    g_free(s->cluster_cache);
-    qemu_vfree(s->cluster_data);
     qcrypto_block_free(s->crypto);
     qapi_free_QCryptoBlockOpenOptions(s->crypto_opts);
     return ret;
@@ -1820,15 +1808,13 @@ static coroutine_fn int qcow2_co_preadv(BlockDriverState *bs, uint64_t offset,
                 assert(s->crypto);
                 assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
                 assert((cur_bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
-                Error *err = NULL;
                 if (qcrypto_block_decrypt(s->crypto,
                                           (s->crypt_physical_offset ?
                                            cluster_offset + offset_in_cluster :
                                            offset) >> BDRV_SECTOR_BITS,
                                           cluster_data,
                                           cur_bytes,
-                                          &err) < 0) {
-                    error_free(err);
+                                          NULL) < 0) {
                     ret = -EIO;
                     goto fail;
                 }
@@ -1942,7 +1928,6 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset,
         qemu_iovec_concat(&hd_qiov, qiov, bytes_done, cur_bytes);
 
         if (bs->encrypted) {
-            Error *err = NULL;
             assert(s->crypto);
             if (!cluster_data) {
                 cluster_data = qemu_try_blockalign(bs->file->bs,
@@ -1963,8 +1948,7 @@ static coroutine_fn int qcow2_co_pwritev(BlockDriverState *bs, uint64_t offset,
                                        cluster_offset + offset_in_cluster :
                                        offset) >> BDRV_SECTOR_BITS,
                                       cluster_data,
-                                      cur_bytes, &err) < 0) {
-                error_free(err);
+                                      cur_bytes, NULL) < 0) {
                 ret = -EIO;
                 goto fail;
             }

dump.c

@@ -1695,10 +1695,8 @@ static void dump_process(DumpState *s, Error **errp)
 
 static void *dump_thread(void *data)
 {
-    Error *err = NULL;
     DumpState *s = (DumpState *)data;
-    dump_process(s, &err);
-    error_free(err);
+    dump_process(s, NULL);
     return NULL;
 }
 

hw/block/nvme.c

@@ -615,7 +615,7 @@ static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         result = blk_enable_write_cache(n->conf.blk);
         break;
     case NVME_NUMBER_OF_QUEUES:
-        result = cpu_to_le32((n->num_queues - 1) | ((n->num_queues - 1) << 16));
+        result = cpu_to_le32((n->num_queues - 2) | ((n->num_queues - 2) << 16));
         break;
     default:
         return NVME_INVALID_FIELD | NVME_DNR;
@@ -636,7 +636,7 @@ static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
         break;
     case NVME_NUMBER_OF_QUEUES:
         req->cqe.result =
-            cpu_to_le32((n->num_queues - 1) | ((n->num_queues - 1) << 16));
+            cpu_to_le32((n->num_queues - 2) | ((n->num_queues - 2) << 16));
         break;
     default:
         return NVME_INVALID_FIELD | NVME_DNR;

include/qemu/throttle.h

@@ -63,7 +63,7 @@ typedef enum {
  * - The bkt.avg rate does not apply until the bucket is full,
  *   allowing the user to do bursts until then. The I/O limit during
  *   bursts is bkt.max. To enforce this limit we keep an additional
- *   bucket in bkt.burst_length that leaks at a rate of bkt.max units
+ *   bucket in bkt.burst_level that leaks at a rate of bkt.max units
  *   per second.
  *
  * - Because of all of the above, the user can perform I/O at a
@@ -77,11 +77,11 @@ typedef enum {
  */
 
 typedef struct LeakyBucket {
-    double  avg;              /* average goal in units per second */
-    double  max;              /* leaky bucket max burst in units */
+    uint64_t avg;             /* average goal in units per second */
+    uint64_t max;             /* leaky bucket max burst in units */
     double  level;            /* bucket level in units */
     double  burst_level;      /* bucket level in units (for computing bursts) */
-    unsigned burst_length;    /* max length of the burst period, in seconds */
+    uint64_t burst_length;    /* max length of the burst period, in seconds */
 } LeakyBucket;
 
 /* The following structure is used to configure a ThrottleState

qemu-doc.texi

@@ -1066,10 +1066,11 @@ in a configuration file provided via '-readconfig' or directly on the
 command line.
 
 If the initiator-name is not specified qemu will use a default name
-of 'iqn.2008-11.org.linux-kvm[:<name>'] where <name> is the name of the
+of 'iqn.2008-11.org.linux-kvm[:<uuid>'] where <uuid> is the UUID of the
+virtual machine. If the UUID is not specified qemu will use
+'iqn.2008-11.org.linux-kvm[:<name>'] where <name> is the name of the
 virtual machine.
 
-
 @example
 Setting a specific initiator name to use when logging in to the target
 -iscsi initiator-name=iqn.qemu.test:my-initiator

tests/docker/docker.py

@@ -13,12 +13,14 @@
 
 import os
 import sys
+sys.path.append(os.path.join(os.path.dirname(__file__),
+                             '..', '..', 'scripts'))
+import argparse
 import subprocess
 import json
 import hashlib
 import atexit
 import uuid
-import argparse
 import tempfile
 import re
 import signal

tests/migration/guestperf/shell.py

@@ -18,12 +18,14 @@
 #
 
 
-import argparse
-import fnmatch
 import os
 import os.path
-import platform
 import sys
+sys.path.append(os.path.join(os.path.dirname(__file__),
+                             '..', '..', '..', 'scripts'))
+import argparse
+import fnmatch
+import platform
 
 from guestperf.hardware import Hardware
 from guestperf.engine import Engine

tests/test-throttle.c

@@ -284,13 +284,14 @@ static void test_enabled(void)
     for (i = 0; i < BUCKETS_COUNT; i++) {
         throttle_config_init(&cfg);
         set_cfg_value(false, i, 150);
+        g_assert(throttle_is_valid(&cfg, NULL));
         g_assert(throttle_enabled(&cfg));
     }
 
     for (i = 0; i < BUCKETS_COUNT; i++) {
         throttle_config_init(&cfg);
         set_cfg_value(false, i, -150);
-        g_assert(!throttle_enabled(&cfg));
+        g_assert(!throttle_is_valid(&cfg, NULL));
     }
 }
 
@@ -377,6 +378,82 @@ static void test_is_valid(void)
     test_is_valid_for_value(1, true);
 }
 
+static void test_ranges(void)
+{
+    int i;
+
+    for (i = 0; i < BUCKETS_COUNT; i++) {
+        LeakyBucket *b = &cfg.buckets[i];
+        throttle_config_init(&cfg);
+
+        /* avg = 0 means throttling is disabled, but the config is valid */
+        b->avg = 0;
+        g_assert(throttle_is_valid(&cfg, NULL));
+        g_assert(!throttle_enabled(&cfg));
+
+        /* These are valid configurations (values <= THROTTLE_VALUE_MAX) */
+        b->avg = 1;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = THROTTLE_VALUE_MAX;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = THROTTLE_VALUE_MAX;
+        b->max = THROTTLE_VALUE_MAX;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        /* Values over THROTTLE_VALUE_MAX are not allowed */
+        b->avg = THROTTLE_VALUE_MAX + 1;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+
+        b->avg = THROTTLE_VALUE_MAX;
+        b->max = THROTTLE_VALUE_MAX + 1;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+
+        /* burst_length must be between 1 and THROTTLE_VALUE_MAX */
+        b->avg = 1;
+        b->max = 1;
+        b->burst_length = 0;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = 1;
+        b->burst_length = 1;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = 1;
+        b->burst_length = THROTTLE_VALUE_MAX;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = 1;
+        b->burst_length = THROTTLE_VALUE_MAX + 1;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+
+        /* burst_length * max cannot exceed THROTTLE_VALUE_MAX */
+        b->avg = 1;
+        b->max = 2;
+        b->burst_length = THROTTLE_VALUE_MAX / 2;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = 3;
+        b->burst_length = THROTTLE_VALUE_MAX / 2;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = THROTTLE_VALUE_MAX;
+        b->burst_length = 1;
+        g_assert(throttle_is_valid(&cfg, NULL));
+
+        b->avg = 1;
+        b->max = THROTTLE_VALUE_MAX;
+        b->burst_length = 2;
+        g_assert(!throttle_is_valid(&cfg, NULL));
+    }
+}
+
 static void test_max_is_missing_limit(void)
 {
     int i;
@@ -668,6 +745,7 @@ int main(int argc, char **argv)
     g_test_add_func("/throttle/config/enabled",     test_enabled);
     g_test_add_func("/throttle/config/conflicting", test_conflicting_config);
     g_test_add_func("/throttle/config/is_valid",    test_is_valid);
+    g_test_add_func("/throttle/config/ranges",      test_ranges);
     g_test_add_func("/throttle/config/max",         test_max_is_missing_limit);
     g_test_add_func("/throttle/config/iops_size",
                     test_iops_size_is_missing_limit);

util/oslib-posix.c

@@ -530,6 +530,7 @@ void *qemu_alloc_stack(size_t *sz)
     ptr = mmap(NULL, *sz, PROT_READ | PROT_WRITE,
                MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
     if (ptr == MAP_FAILED) {
+        perror("failed to allocate memory for stack");
         abort();
     }
 
@@ -544,6 +545,7 @@ void *qemu_alloc_stack(size_t *sz)
     guardpage = ptr;
 #endif
     if (mprotect(guardpage, pagesz, PROT_NONE) != 0) {
+        perror("failed to set up stack guard page");
         abort();
     }
 

util/throttle.c

@@ -95,23 +95,36 @@ static int64_t throttle_do_compute_wait(double limit, double extra)
 int64_t throttle_compute_wait(LeakyBucket *bkt)
 {
     double extra; /* the number of extra units blocking the io */
+    double bucket_size;   /* I/O before throttling to bkt->avg */
+    double burst_bucket_size; /* Before throttling to bkt->max */
 
     if (!bkt->avg) {
         return 0;
     }
 
-    /* If the bucket is full then we have to wait */
-    extra = bkt->level - bkt->max * bkt->burst_length;
+    if (!bkt->max) {
+        /* If bkt->max is 0 we still want to allow short bursts of I/O
+         * from the guest, otherwise every other request will be throttled
+         * and performance will suffer considerably. */
+        bucket_size = (double) bkt->avg / 10;
+        burst_bucket_size = 0;
+    } else {
+        /* If we have a burst limit then we have to wait until all I/O
+         * at burst rate has finished before throttling to bkt->avg */
+        bucket_size = bkt->max * bkt->burst_length;
+        burst_bucket_size = (double) bkt->max / 10;
+    }
+
+    /* If the main bucket is full then we have to wait */
+    extra = bkt->level - bucket_size;
     if (extra > 0) {
         return throttle_do_compute_wait(bkt->avg, extra);
     }
 
-    /* If the bucket is not full yet we have to make sure that we
-     * fulfill the goal of bkt->max units per second. */
+    /* If the main bucket is not full yet we still have to check the
+     * burst bucket in order to enforce the burst limit */
     if (bkt->burst_length > 1) {
-        /* We use 1/10 of the max value to smooth the throttling.
-         * See throttle_fix_bucket() for more details. */
-        extra = bkt->burst_level - bkt->max / 10;
+        extra = bkt->burst_level - burst_bucket_size;
         if (extra > 0) {
             return throttle_do_compute_wait(bkt->max, extra);
         }
@@ -324,32 +337,35 @@ bool throttle_is_valid(ThrottleConfig *cfg, Error **errp)
     }
 
     for (i = 0; i < BUCKETS_COUNT; i++) {
-        if (cfg->buckets[i].avg < 0 ||
-            cfg->buckets[i].max < 0 ||
-            cfg->buckets[i].avg > THROTTLE_VALUE_MAX ||
-            cfg->buckets[i].max > THROTTLE_VALUE_MAX) {
+        LeakyBucket *bkt = &cfg->buckets[i];
+        if (bkt->avg > THROTTLE_VALUE_MAX || bkt->max > THROTTLE_VALUE_MAX) {
             error_setg(errp, "bps/iops/max values must be within [0, %lld]",
                        THROTTLE_VALUE_MAX);
             return false;
         }
 
-        if (!cfg->buckets[i].burst_length) {
+        if (!bkt->burst_length) {
             error_setg(errp, "the burst length cannot be 0");
             return false;
         }
 
-        if (cfg->buckets[i].burst_length > 1 && !cfg->buckets[i].max) {
+        if (bkt->burst_length > 1 && !bkt->max) {
             error_setg(errp, "burst length set without burst rate");
             return false;
         }
 
-        if (cfg->buckets[i].max && !cfg->buckets[i].avg) {
+        if (bkt->max && bkt->burst_length > THROTTLE_VALUE_MAX / bkt->max) {
+            error_setg(errp, "burst length too high for this burst rate");
+            return false;
+        }
+
+        if (bkt->max && !bkt->avg) {
             error_setg(errp, "bps_max/iops_max require corresponding"
                        " bps/iops values");
             return false;
         }
 
-        if (cfg->buckets[i].max && cfg->buckets[i].max < cfg->buckets[i].avg) {
+        if (bkt->max && bkt->max < bkt->avg) {
             error_setg(errp, "bps_max/iops_max cannot be lower than bps/iops");
             return false;
         }
@@ -358,36 +374,6 @@ bool throttle_is_valid(ThrottleConfig *cfg, Error **errp)
     return true;
 }
 
-/* fix bucket parameters */
-static void throttle_fix_bucket(LeakyBucket *bkt)
-{
-    double min;
-
-    /* zero bucket level */
-    bkt->level = bkt->burst_level = 0;
-
-    /* The following is done to cope with the Linux CFQ block scheduler
-     * which regroup reads and writes by block of 100ms in the guest.
-     * When they are two process one making reads and one making writes cfq
-     * make a pattern looking like the following:
-     * WWWWWWWWWWWRRRRRRRRRRRRRRWWWWWWWWWWWWWwRRRRRRRRRRRRRRRRR
-     * Having a max burst value of 100ms of the average will help smooth the
-     * throttling
-     */
-    min = bkt->avg / 10;
-    if (bkt->avg && !bkt->max) {
-        bkt->max = min;
-    }
-}
-
-/* undo internal bucket parameter changes (see throttle_fix_bucket()) */
-static void throttle_unfix_bucket(LeakyBucket *bkt)
-{
-    if (bkt->max < bkt->avg) {
-        bkt->max = 0;
-    }
-}
-
 /* Used to configure the throttle
  *
  * @ts: the throttle state we are working on
@@ -402,8 +388,10 @@ void throttle_config(ThrottleState *ts,
 
     ts->cfg = *cfg;
 
+    /* Zero bucket level */
     for (i = 0; i < BUCKETS_COUNT; i++) {
-        throttle_fix_bucket(&ts->cfg.buckets[i]);
+        ts->cfg.buckets[i].level = 0;
+        ts->cfg.buckets[i].burst_level = 0;
     }
 
     ts->previous_leak = qemu_clock_get_ns(clock_type);
@@ -416,13 +404,7 @@ void throttle_config(ThrottleState *ts,
  */
 void throttle_get_config(ThrottleState *ts, ThrottleConfig *cfg)
 {
-    int i;
-
     *cfg = ts->cfg;
-
-    for (i = 0; i < BUCKETS_COUNT; i++) {
-        throttle_unfix_bucket(&cfg->buckets[i]);
-    }
 }