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authorLinus Torvalds2019-05-07 18:14:36 -0700
committerLinus Torvalds2019-05-07 18:14:36 -0700
commit67a242223958d628f0ba33283668e3ddd192d057 (patch)
treea39e7039e9a2ef9ab46f8ba561175dbdc6101d11 /include
parent8b35ad6232c462b02e397e87ce702bcddd4ba543 (diff)
parentb8753433fc611e23e31300e1d099001a08955c88 (diff)
Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe: "Nothing major in this series, just fixes and improvements all over the map. This contains: - Series of fixes for sed-opal (David, Jonas) - Fixes and performance tweaks for BFQ (via Paolo) - Set of fixes for bcache (via Coly) - Set of fixes for md (via Song) - Enabling multi-page for passthrough requests (Ming) - Queue release fix series (Ming) - Device notification improvements (Martin) - Propagate underlying device rotational status in loop (Holger) - Removal of mtip32xx trim support, which has been disabled for years (Christoph) - Improvement and cleanup of nvme command handling (Christoph) - Add block SPDX tags (Christoph) - Cleanup/hardening of bio/bvec iteration (Christoph) - A few NVMe pull requests (Christoph) - Removal of CONFIG_LBDAF (Christoph) - Various little fixes here and there" * tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits) block: fix mismerge in bvec_advance block: don't drain in-progress dispatch in blk_cleanup_queue() blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release blk-mq: always free hctx after request queue is freed blk-mq: split blk_mq_alloc_and_init_hctx into two parts blk-mq: free hw queue's resource in hctx's release handler blk-mq: move cancel of requeue_work into blk_mq_release blk-mq: grab .q_usage_counter when queuing request from plug code path block: fix function name in comment nvmet: protect discovery change log event list iteration nvme: mark nvme_core_init and nvme_core_exit static nvme: move command size checks to the core nvme-fabrics: check more command sizes nvme-pci: check more command sizes nvme-pci: remove an unneeded variable initialization nvme-pci: unquiesce admin queue on shutdown nvme-pci: shutdown on timeout during deletion nvme-pci: fix psdt field for single segment sgls nvme-multipath: don't print ANA group state by default nvme-multipath: split bios with the ns_head bio_set before submitting ...
Diffstat (limited to 'include')
-rw-r--r--include/linux/bio.h20
-rw-r--r--include/linux/blk-mq-rdma.h1
-rw-r--r--include/linux/blk-mq.h2
-rw-r--r--include/linux/blk_types.h29
-rw-r--r--include/linux/blkdev.h42
-rw-r--r--include/linux/bsg-lib.h16
-rw-r--r--include/linux/bvec.h36
-rw-r--r--include/linux/genhd.h20
-rw-r--r--include/linux/kernel.h14
-rw-r--r--include/linux/nvme-rdma.h2
-rw-r--r--include/linux/sed-opal.h10
-rw-r--r--include/linux/types.h5
-rw-r--r--include/uapi/linux/sed-opal.h11
-rw-r--r--include/xen/xen.h4
14 files changed, 92 insertions, 120 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h
index e584673c1881..ea73df36529a 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -1,19 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2001 Jens Axboe <axboe@suse.de>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public Licens
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
#ifndef __LINUX_BIO_H
#define __LINUX_BIO_H
@@ -134,9 +121,8 @@ static inline bool bio_next_segment(const struct bio *bio,
* drivers should _never_ use the all version - the bio may have been split
* before it got to the driver and the driver won't own all of it
*/
-#define bio_for_each_segment_all(bvl, bio, i, iter) \
- for (i = 0, bvl = bvec_init_iter_all(&iter); \
- bio_next_segment((bio), &iter); i++)
+#define bio_for_each_segment_all(bvl, bio, iter) \
+ for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
unsigned bytes)
diff --git a/include/linux/blk-mq-rdma.h b/include/linux/blk-mq-rdma.h
index 7b6ecf9ac4c3..5cc5f0f36218 100644
--- a/include/linux/blk-mq-rdma.h
+++ b/include/linux/blk-mq-rdma.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_BLK_MQ_RDMA_H
#define _LINUX_BLK_MQ_RDMA_H
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index db29928de467..15d1aa53d96c 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -70,6 +70,8 @@ struct blk_mq_hw_ctx {
struct dentry *sched_debugfs_dir;
#endif
+ struct list_head hctx_list;
+
/* Must be the last member - see also blk_mq_hw_ctx_size(). */
struct srcu_struct srcu[0];
};
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 791fee35df88..be418275763c 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -215,21 +215,24 @@ struct bio {
/*
* bio flags
*/
-#define BIO_NO_PAGE_REF 0 /* don't put release vec pages */
-#define BIO_SEG_VALID 1 /* bi_phys_segments valid */
-#define BIO_CLONED 2 /* doesn't own data */
-#define BIO_BOUNCED 3 /* bio is a bounce bio */
-#define BIO_USER_MAPPED 4 /* contains user pages */
-#define BIO_NULL_MAPPED 5 /* contains invalid user pages */
-#define BIO_QUIET 6 /* Make BIO Quiet */
-#define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
-#define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
-#define BIO_THROTTLED 9 /* This bio has already been subjected to
+enum {
+ BIO_NO_PAGE_REF, /* don't put release vec pages */
+ BIO_SEG_VALID, /* bi_phys_segments valid */
+ BIO_CLONED, /* doesn't own data */
+ BIO_BOUNCED, /* bio is a bounce bio */
+ BIO_USER_MAPPED, /* contains user pages */
+ BIO_NULL_MAPPED, /* contains invalid user pages */
+ BIO_QUIET, /* Make BIO Quiet */
+ BIO_CHAIN, /* chained bio, ->bi_remaining in effect */
+ BIO_REFFED, /* bio has elevated ->bi_cnt */
+ BIO_THROTTLED, /* This bio has already been subjected to
* throttling rules. Don't do it again. */
-#define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
+ BIO_TRACE_COMPLETION, /* bio_endio() should trace the final completion
* of this bio. */
-#define BIO_QUEUE_ENTERED 11 /* can use blk_queue_enter_live() */
-#define BIO_TRACKED 12 /* set if bio goes through the rq_qos path */
+ BIO_QUEUE_ENTERED, /* can use blk_queue_enter_live() */
+ BIO_TRACKED, /* set if bio goes through the rq_qos path */
+ BIO_FLAG_LAST
+};
/* See BVEC_POOL_OFFSET below before adding new flags */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 317ab30d2904..1aafeb923e7b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -535,6 +535,13 @@ struct request_queue {
struct mutex sysfs_lock;
+ /*
+ * for reusing dead hctx instance in case of updating
+ * nr_hw_queues
+ */
+ struct list_head unused_hctx_list;
+ spinlock_t unused_hctx_lock;
+
atomic_t mq_freeze_depth;
#if defined(CONFIG_BLK_DEV_BSG)
@@ -640,6 +647,13 @@ static inline bool blk_account_rq(struct request *rq)
#define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
+#define rq_dma_dir(rq) \
+ (op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
+
+#define dma_map_bvec(dev, bv, dir, attrs) \
+ dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
+ (dir), (attrs))
+
static inline bool queue_is_mq(struct request_queue *q)
{
return q->mq_ops;
@@ -931,6 +945,17 @@ static inline unsigned int blk_rq_payload_bytes(struct request *rq)
return blk_rq_bytes(rq);
}
+/*
+ * Return the first full biovec in the request. The caller needs to check that
+ * there are any bvecs before calling this helper.
+ */
+static inline struct bio_vec req_bvec(struct request *rq)
+{
+ if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
+ return rq->special_vec;
+ return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
+}
+
static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
int op)
{
@@ -1051,7 +1076,6 @@ extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
sector_t offset);
extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
-extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
extern int blk_queue_dma_drain(struct request_queue *q,
dma_drain_needed_fn *dma_drain_needed,
@@ -1547,6 +1571,17 @@ static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
}
+/*
+ * Return the first bvec that contains integrity data. Only drivers that are
+ * limited to a single integrity segment should use this helper.
+ */
+static inline struct bio_vec *rq_integrity_vec(struct request *rq)
+{
+ if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
+ return NULL;
+ return rq->bio->bi_integrity->bip_vec;
+}
+
#else /* CONFIG_BLK_DEV_INTEGRITY */
struct bio;
@@ -1621,6 +1656,11 @@ static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
return 0;
}
+static inline struct bio_vec *rq_integrity_vec(struct request *rq)
+{
+ return NULL;
+}
+
#endif /* CONFIG_BLK_DEV_INTEGRITY */
struct block_device_operations {
diff --git a/include/linux/bsg-lib.h b/include/linux/bsg-lib.h
index 7f14517a559b..960988d42f77 100644
--- a/include/linux/bsg-lib.h
+++ b/include/linux/bsg-lib.h
@@ -1,24 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* BSG helper library
*
* Copyright (C) 2008 James Smart, Emulex Corporation
* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
* Copyright (C) 2011 Mike Christie
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
*/
#ifndef _BLK_BSG_
#define _BLK_BSG_
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index ff13cbc1887d..a032f01e928c 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -1,21 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0 */
/*
* bvec iterator
*
* Copyright (C) 2001 Ming Lei <ming.lei@canonical.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- *
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public Licens
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
*/
#ifndef __LINUX_BVEC_ITER_H
#define __LINUX_BVEC_ITER_H
@@ -51,11 +38,6 @@ struct bvec_iter_all {
unsigned done;
};
-static inline struct page *bvec_nth_page(struct page *page, int idx)
-{
- return idx == 0 ? page : nth_page(page, idx);
-}
-
/*
* various member access, note that bio_data should of course not be used
* on highmem page vectors
@@ -92,8 +74,8 @@ static inline struct page *bvec_nth_page(struct page *page, int idx)
PAGE_SIZE - bvec_iter_offset((bvec), (iter)))
#define bvec_iter_page(bvec, iter) \
- bvec_nth_page(mp_bvec_iter_page((bvec), (iter)), \
- mp_bvec_iter_page_idx((bvec), (iter)))
+ (mp_bvec_iter_page((bvec), (iter)) + \
+ mp_bvec_iter_page_idx((bvec), (iter)))
#define bvec_iter_bvec(bvec, iter) \
((struct bio_vec) { \
@@ -157,11 +139,10 @@ static inline void bvec_advance(const struct bio_vec *bvec,
struct bio_vec *bv = &iter_all->bv;
if (iter_all->done) {
- bv->bv_page = nth_page(bv->bv_page, 1);
+ bv->bv_page++;
bv->bv_offset = 0;
} else {
- bv->bv_page = bvec_nth_page(bvec->bv_page, bvec->bv_offset /
- PAGE_SIZE);
+ bv->bv_page = bvec->bv_page + (bvec->bv_offset >> PAGE_SHIFT);
bv->bv_offset = bvec->bv_offset & ~PAGE_MASK;
}
bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset,
@@ -184,7 +165,7 @@ static inline void mp_bvec_last_segment(const struct bio_vec *bvec,
unsigned total = bvec->bv_offset + bvec->bv_len;
unsigned last_page = (total - 1) / PAGE_SIZE;
- seg->bv_page = bvec_nth_page(bvec->bv_page, last_page);
+ seg->bv_page = bvec->bv_page + last_page;
/* the whole segment is inside the last page */
if (bvec->bv_offset >= last_page * PAGE_SIZE) {
@@ -196,9 +177,4 @@ static inline void mp_bvec_last_segment(const struct bio_vec *bvec,
}
}
-#define mp_bvec_for_each_page(pg, bv, i) \
- for (i = (bv)->bv_offset / PAGE_SIZE; \
- (i <= (((bv)->bv_offset + (bv)->bv_len - 1) / PAGE_SIZE)) && \
- (pg = bvec_nth_page((bv)->bv_page, i)); i += 1)
-
#endif /* __LINUX_BVEC_ITER_H */
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 06c0fd594097..8b5330dd5ac0 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -150,6 +150,13 @@ enum {
DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */
};
+enum {
+ /* Poll even if events_poll_msecs is unset */
+ DISK_EVENT_FLAG_POLL = 1 << 0,
+ /* Forward events to udev */
+ DISK_EVENT_FLAG_UEVENT = 1 << 1,
+};
+
struct disk_part_tbl {
struct rcu_head rcu_head;
int len;
@@ -184,8 +191,8 @@ struct gendisk {
char disk_name[DISK_NAME_LEN]; /* name of major driver */
char *(*devnode)(struct gendisk *gd, umode_t *mode);
- unsigned int events; /* supported events */
- unsigned int async_events; /* async events, subset of all */
+ unsigned short events; /* supported events */
+ unsigned short event_flags; /* flags related to event processing */
/* Array of pointers to partitions indexed by partno.
* Protected with matching bdev lock but stat and other
@@ -610,6 +617,7 @@ struct unixware_disklabel {
extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
extern void blk_free_devt(dev_t devt);
+extern void blk_invalidate_devt(dev_t devt);
extern dev_t blk_lookup_devt(const char *name, int partno);
extern char *disk_name (struct gendisk *hd, int partno, char *buf);
@@ -714,7 +722,7 @@ static inline void hd_free_part(struct hd_struct *part)
*/
static inline sector_t part_nr_sects_read(struct hd_struct *part)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
sector_t nr_sects;
unsigned seq;
do {
@@ -722,7 +730,7 @@ static inline sector_t part_nr_sects_read(struct hd_struct *part)
nr_sects = part->nr_sects;
} while (read_seqcount_retry(&part->nr_sects_seq, seq));
return nr_sects;
-#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
+#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
sector_t nr_sects;
preempt_disable();
@@ -741,11 +749,11 @@ static inline sector_t part_nr_sects_read(struct hd_struct *part)
*/
static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
{
-#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
+#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
write_seqcount_begin(&part->nr_sects_seq);
part->nr_sects = size;
write_seqcount_end(&part->nr_sects_seq);
-#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
+#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
preempt_disable();
part->nr_sects = size;
preempt_enable();
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2d14e21c16c0..a3b59d143afb 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -17,6 +17,7 @@
#include <asm/byteorder.h>
#include <asm/div64.h>
#include <uapi/linux/kernel.h>
+#include <asm/div64.h>
#define STACK_MAGIC 0xdeadbeef
@@ -175,18 +176,7 @@
#define _RET_IP_ (unsigned long)__builtin_return_address(0)
#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
-#ifdef CONFIG_LBDAF
-# define sector_div(a, b) do_div(a, b)
-#else
-# define sector_div(n, b)( \
-{ \
- int _res; \
- _res = (n) % (b); \
- (n) /= (b); \
- _res; \
-} \
-)
-#endif
+#define sector_div(a, b) do_div(a, b)
/**
* upper_32_bits - return bits 32-63 of a number
diff --git a/include/linux/nvme-rdma.h b/include/linux/nvme-rdma.h
index 3aa97b98dc89..3ec8e50efa16 100644
--- a/include/linux/nvme-rdma.h
+++ b/include/linux/nvme-rdma.h
@@ -77,7 +77,7 @@ struct nvme_rdma_cm_rep {
* struct nvme_rdma_cm_rej - rdma connect reject
*
* @recfmt: format of the RDMA Private Data
- * @fsts: error status for the associated connect request
+ * @sts: error status for the associated connect request
*/
struct nvme_rdma_cm_rej {
__le16 recfmt;
diff --git a/include/linux/sed-opal.h b/include/linux/sed-opal.h
index 04b124fca51e..3e76b6d7d97f 100644
--- a/include/linux/sed-opal.h
+++ b/include/linux/sed-opal.h
@@ -1,18 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright © 2016 Intel Corporation
*
* Authors:
* Rafael Antognolli <rafael.antognolli@intel.com>
* Scott Bauer <scott.bauer@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
*/
#ifndef LINUX_OPAL_H
diff --git a/include/linux/types.h b/include/linux/types.h
index cc0dbbe551d5..231114ae38f4 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -127,13 +127,8 @@ typedef s64 int64_t;
*
* blkcnt_t is the type of the inode's block count.
*/
-#ifdef CONFIG_LBDAF
typedef u64 sector_t;
typedef u64 blkcnt_t;
-#else
-typedef unsigned long sector_t;
-typedef unsigned long blkcnt_t;
-#endif
/*
* The type of an index into the pagecache.
diff --git a/include/uapi/linux/sed-opal.h b/include/uapi/linux/sed-opal.h
index 627624d35030..33e53b80cd1f 100644
--- a/include/uapi/linux/sed-opal.h
+++ b/include/uapi/linux/sed-opal.h
@@ -5,15 +5,6 @@
* Authors:
* Rafael Antognolli <rafael.antognolli@intel.com>
* Scott Bauer <scott.bauer@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
*/
#ifndef _UAPI_SED_OPAL_H
@@ -58,7 +49,7 @@ struct opal_key {
struct opal_lr_act {
struct opal_key key;
__u32 sum;
- __u8 num_lrs;
+ __u8 num_lrs;
__u8 lr[OPAL_MAX_LRS];
__u8 align[2]; /* Align to 8 byte boundary */
};
diff --git a/include/xen/xen.h b/include/xen/xen.h
index 19d032373de5..19a72f591e2b 100644
--- a/include/xen/xen.h
+++ b/include/xen/xen.h
@@ -43,8 +43,10 @@ extern struct hvm_start_info pvh_start_info;
#endif /* CONFIG_XEN_DOM0 */
struct bio_vec;
+struct page;
+
bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
- const struct bio_vec *vec2);
+ const struct page *page);
#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON)
extern u64 xen_saved_max_mem_size;