mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Qian Cai](/assets/img/avatar_default.png)
When running heavy memory pressure workloads, this 5+ old system is
throwing endless warnings below because disk IO is too slow to recover
from swapping. Since the volume from alloc_iova_fast() could be large,
once it calls printk(), it will trigger disk IO (writing to the log
files) and pending softirqs which could cause an infinite loop and make
no progress for days by the ongoimng memory reclaim. This is the counter
part for Intel where the AMD part has already been merged. See the
commit 3d70889532
("iommu/amd: Silence warnings under memory
pressure"). Since the allocation failure will be reported in
intel_alloc_iova(), so just call dev_err_once() there because even the
"ratelimited" is too much, and silence the one in alloc_iova_mem() to
avoid the expensive warn_alloc().
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
slab_out_of_memory: 66 callbacks suppressed
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
cache: iommu_iova, object size: 40, buffer size: 448, default order:
0, min order: 0
node 0: slabs: 1822, objs: 16398, free: 0
node 1: slabs: 2051, objs: 18459, free: 31
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
cache: iommu_iova, object size: 40, buffer size: 448, default order:
0, min order: 0
node 0: slabs: 1822, objs: 16398, free: 0
node 1: slabs: 2051, objs: 18459, free: 31
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
cache: iommu_iova, object size: 40, buffer size: 448, default order:
0, min order: 0
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
node 0: slabs: 697, objs: 4182, free: 0
node 0: slabs: 697, objs: 4182, free: 0
node 0: slabs: 697, objs: 4182, free: 0
node 0: slabs: 697, objs: 4182, free: 0
node 1: slabs: 381, objs: 2286, free: 27
node 1: slabs: 381, objs: 2286, free: 27
node 1: slabs: 381, objs: 2286, free: 27
node 1: slabs: 381, objs: 2286, free: 27
node 0: slabs: 1822, objs: 16398, free: 0
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
node 1: slabs: 2051, objs: 18459, free: 31
node 0: slabs: 697, objs: 4182, free: 0
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
node 1: slabs: 381, objs: 2286, free: 27
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
node 0: slabs: 697, objs: 4182, free: 0
node 1: slabs: 381, objs: 2286, free: 27
hpsa 0000:03:00.0: DMAR: Allocating 1-page iova failed
warn_alloc: 96 callbacks suppressed
kworker/11:1H: page allocation failure: order:0,
mode:0xa20(GFP_ATOMIC), nodemask=(null),cpuset=/,mems_allowed=0-1
CPU: 11 PID: 1642 Comm: kworker/11:1H Tainted: G B
Hardware name: HP ProLiant XL420 Gen9/ProLiant XL420 Gen9, BIOS U19
12/27/2015
Workqueue: kblockd blk_mq_run_work_fn
Call Trace:
dump_stack+0xa0/0xea
warn_alloc.cold.94+0x8a/0x12d
__alloc_pages_slowpath+0x1750/0x1870
__alloc_pages_nodemask+0x58a/0x710
alloc_pages_current+0x9c/0x110
alloc_slab_page+0xc9/0x760
allocate_slab+0x48f/0x5d0
new_slab+0x46/0x70
___slab_alloc+0x4ab/0x7b0
__slab_alloc+0x43/0x70
kmem_cache_alloc+0x2dd/0x450
SLUB: Unable to allocate memory on node -1, gfp=0xa20(GFP_ATOMIC)
alloc_iova+0x33/0x210
cache: skbuff_head_cache, object size: 208, buffer size: 640, default
order: 0, min order: 0
node 0: slabs: 697, objs: 4182, free: 0
alloc_iova_fast+0x62/0x3d1
node 1: slabs: 381, objs: 2286, free: 27
intel_alloc_iova+0xce/0xe0
intel_map_sg+0xed/0x410
scsi_dma_map+0xd7/0x160
scsi_queue_rq+0xbf7/0x1310
blk_mq_dispatch_rq_list+0x4d9/0xbc0
blk_mq_sched_dispatch_requests+0x24a/0x300
__blk_mq_run_hw_queue+0x156/0x230
blk_mq_run_work_fn+0x3b/0x40
process_one_work+0x579/0xb90
worker_thread+0x63/0x5b0
kthread+0x1e6/0x210
ret_from_fork+0x3a/0x50
Mem-Info:
active_anon:2422723 inactive_anon:361971 isolated_anon:34403
active_file:2285 inactive_file:1838 isolated_file:0
unevictable:0 dirty:1 writeback:5 unstable:0
slab_reclaimable:13972 slab_unreclaimable:453879
mapped:2380 shmem:154 pagetables:6948 bounce:0
free:19133 free_pcp:7363 free_cma:0
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
1048 lines
26 KiB
C
1048 lines
26 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright © 2006-2009, Intel Corporation.
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*
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* Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
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*/
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#include <linux/iova.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/smp.h>
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#include <linux/bitops.h>
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#include <linux/cpu.h>
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/* The anchor node sits above the top of the usable address space */
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#define IOVA_ANCHOR ~0UL
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static bool iova_rcache_insert(struct iova_domain *iovad,
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unsigned long pfn,
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unsigned long size);
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static unsigned long iova_rcache_get(struct iova_domain *iovad,
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unsigned long size,
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unsigned long limit_pfn);
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static void init_iova_rcaches(struct iova_domain *iovad);
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static void free_iova_rcaches(struct iova_domain *iovad);
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static void fq_destroy_all_entries(struct iova_domain *iovad);
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static void fq_flush_timeout(struct timer_list *t);
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void
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init_iova_domain(struct iova_domain *iovad, unsigned long granule,
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unsigned long start_pfn)
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{
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/*
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* IOVA granularity will normally be equal to the smallest
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* supported IOMMU page size; both *must* be capable of
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* representing individual CPU pages exactly.
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*/
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BUG_ON((granule > PAGE_SIZE) || !is_power_of_2(granule));
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spin_lock_init(&iovad->iova_rbtree_lock);
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iovad->rbroot = RB_ROOT;
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iovad->cached_node = &iovad->anchor.node;
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iovad->cached32_node = &iovad->anchor.node;
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iovad->granule = granule;
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iovad->start_pfn = start_pfn;
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iovad->dma_32bit_pfn = 1UL << (32 - iova_shift(iovad));
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iovad->max32_alloc_size = iovad->dma_32bit_pfn;
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iovad->flush_cb = NULL;
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iovad->fq = NULL;
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iovad->anchor.pfn_lo = iovad->anchor.pfn_hi = IOVA_ANCHOR;
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rb_link_node(&iovad->anchor.node, NULL, &iovad->rbroot.rb_node);
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rb_insert_color(&iovad->anchor.node, &iovad->rbroot);
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init_iova_rcaches(iovad);
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}
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EXPORT_SYMBOL_GPL(init_iova_domain);
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bool has_iova_flush_queue(struct iova_domain *iovad)
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{
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return !!iovad->fq;
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}
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static void free_iova_flush_queue(struct iova_domain *iovad)
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{
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if (!has_iova_flush_queue(iovad))
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return;
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if (timer_pending(&iovad->fq_timer))
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del_timer(&iovad->fq_timer);
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fq_destroy_all_entries(iovad);
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free_percpu(iovad->fq);
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iovad->fq = NULL;
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iovad->flush_cb = NULL;
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iovad->entry_dtor = NULL;
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}
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int init_iova_flush_queue(struct iova_domain *iovad,
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iova_flush_cb flush_cb, iova_entry_dtor entry_dtor)
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{
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struct iova_fq __percpu *queue;
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int cpu;
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atomic64_set(&iovad->fq_flush_start_cnt, 0);
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atomic64_set(&iovad->fq_flush_finish_cnt, 0);
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queue = alloc_percpu(struct iova_fq);
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if (!queue)
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return -ENOMEM;
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iovad->flush_cb = flush_cb;
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iovad->entry_dtor = entry_dtor;
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for_each_possible_cpu(cpu) {
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struct iova_fq *fq;
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fq = per_cpu_ptr(queue, cpu);
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fq->head = 0;
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fq->tail = 0;
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spin_lock_init(&fq->lock);
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}
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smp_wmb();
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iovad->fq = queue;
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timer_setup(&iovad->fq_timer, fq_flush_timeout, 0);
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atomic_set(&iovad->fq_timer_on, 0);
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return 0;
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}
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EXPORT_SYMBOL_GPL(init_iova_flush_queue);
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static struct rb_node *
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__get_cached_rbnode(struct iova_domain *iovad, unsigned long limit_pfn)
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{
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if (limit_pfn <= iovad->dma_32bit_pfn)
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return iovad->cached32_node;
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return iovad->cached_node;
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}
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static void
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__cached_rbnode_insert_update(struct iova_domain *iovad, struct iova *new)
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{
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if (new->pfn_hi < iovad->dma_32bit_pfn)
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iovad->cached32_node = &new->node;
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else
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iovad->cached_node = &new->node;
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}
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static void
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__cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
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{
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struct iova *cached_iova;
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cached_iova = rb_entry(iovad->cached32_node, struct iova, node);
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if (free == cached_iova ||
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(free->pfn_hi < iovad->dma_32bit_pfn &&
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free->pfn_lo >= cached_iova->pfn_lo)) {
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iovad->cached32_node = rb_next(&free->node);
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iovad->max32_alloc_size = iovad->dma_32bit_pfn;
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}
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cached_iova = rb_entry(iovad->cached_node, struct iova, node);
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if (free->pfn_lo >= cached_iova->pfn_lo)
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iovad->cached_node = rb_next(&free->node);
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}
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/* Insert the iova into domain rbtree by holding writer lock */
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static void
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iova_insert_rbtree(struct rb_root *root, struct iova *iova,
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struct rb_node *start)
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{
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struct rb_node **new, *parent = NULL;
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new = (start) ? &start : &(root->rb_node);
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/* Figure out where to put new node */
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while (*new) {
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struct iova *this = rb_entry(*new, struct iova, node);
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parent = *new;
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if (iova->pfn_lo < this->pfn_lo)
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new = &((*new)->rb_left);
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else if (iova->pfn_lo > this->pfn_lo)
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new = &((*new)->rb_right);
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else {
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WARN_ON(1); /* this should not happen */
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return;
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}
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}
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/* Add new node and rebalance tree. */
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rb_link_node(&iova->node, parent, new);
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rb_insert_color(&iova->node, root);
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}
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static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
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unsigned long size, unsigned long limit_pfn,
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struct iova *new, bool size_aligned)
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{
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struct rb_node *curr, *prev;
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struct iova *curr_iova;
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unsigned long flags;
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unsigned long new_pfn;
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unsigned long align_mask = ~0UL;
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if (size_aligned)
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align_mask <<= fls_long(size - 1);
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/* Walk the tree backwards */
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spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
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if (limit_pfn <= iovad->dma_32bit_pfn &&
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size >= iovad->max32_alloc_size)
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goto iova32_full;
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curr = __get_cached_rbnode(iovad, limit_pfn);
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curr_iova = rb_entry(curr, struct iova, node);
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do {
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limit_pfn = min(limit_pfn, curr_iova->pfn_lo);
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new_pfn = (limit_pfn - size) & align_mask;
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prev = curr;
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curr = rb_prev(curr);
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curr_iova = rb_entry(curr, struct iova, node);
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} while (curr && new_pfn <= curr_iova->pfn_hi);
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if (limit_pfn < size || new_pfn < iovad->start_pfn) {
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iovad->max32_alloc_size = size;
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goto iova32_full;
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}
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/* pfn_lo will point to size aligned address if size_aligned is set */
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new->pfn_lo = new_pfn;
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new->pfn_hi = new->pfn_lo + size - 1;
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/* If we have 'prev', it's a valid place to start the insertion. */
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iova_insert_rbtree(&iovad->rbroot, new, prev);
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__cached_rbnode_insert_update(iovad, new);
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spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
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return 0;
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iova32_full:
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spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
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return -ENOMEM;
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}
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static struct kmem_cache *iova_cache;
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static unsigned int iova_cache_users;
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static DEFINE_MUTEX(iova_cache_mutex);
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struct iova *alloc_iova_mem(void)
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{
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return kmem_cache_zalloc(iova_cache, GFP_ATOMIC | __GFP_NOWARN);
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}
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EXPORT_SYMBOL(alloc_iova_mem);
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void free_iova_mem(struct iova *iova)
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{
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if (iova->pfn_lo != IOVA_ANCHOR)
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kmem_cache_free(iova_cache, iova);
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}
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EXPORT_SYMBOL(free_iova_mem);
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int iova_cache_get(void)
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{
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mutex_lock(&iova_cache_mutex);
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if (!iova_cache_users) {
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iova_cache = kmem_cache_create(
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"iommu_iova", sizeof(struct iova), 0,
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SLAB_HWCACHE_ALIGN, NULL);
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if (!iova_cache) {
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mutex_unlock(&iova_cache_mutex);
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printk(KERN_ERR "Couldn't create iova cache\n");
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return -ENOMEM;
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}
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}
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iova_cache_users++;
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mutex_unlock(&iova_cache_mutex);
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return 0;
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}
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EXPORT_SYMBOL_GPL(iova_cache_get);
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void iova_cache_put(void)
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{
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mutex_lock(&iova_cache_mutex);
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if (WARN_ON(!iova_cache_users)) {
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mutex_unlock(&iova_cache_mutex);
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return;
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}
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iova_cache_users--;
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if (!iova_cache_users)
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kmem_cache_destroy(iova_cache);
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mutex_unlock(&iova_cache_mutex);
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}
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EXPORT_SYMBOL_GPL(iova_cache_put);
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/**
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* alloc_iova - allocates an iova
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* @iovad: - iova domain in question
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* @size: - size of page frames to allocate
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* @limit_pfn: - max limit address
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* @size_aligned: - set if size_aligned address range is required
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* This function allocates an iova in the range iovad->start_pfn to limit_pfn,
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* searching top-down from limit_pfn to iovad->start_pfn. If the size_aligned
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* flag is set then the allocated address iova->pfn_lo will be naturally
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* aligned on roundup_power_of_two(size).
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*/
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struct iova *
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alloc_iova(struct iova_domain *iovad, unsigned long size,
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unsigned long limit_pfn,
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bool size_aligned)
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{
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struct iova *new_iova;
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int ret;
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new_iova = alloc_iova_mem();
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if (!new_iova)
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return NULL;
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ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn + 1,
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new_iova, size_aligned);
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if (ret) {
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free_iova_mem(new_iova);
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return NULL;
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}
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return new_iova;
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}
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EXPORT_SYMBOL_GPL(alloc_iova);
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static struct iova *
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private_find_iova(struct iova_domain *iovad, unsigned long pfn)
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{
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struct rb_node *node = iovad->rbroot.rb_node;
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assert_spin_locked(&iovad->iova_rbtree_lock);
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while (node) {
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struct iova *iova = rb_entry(node, struct iova, node);
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if (pfn < iova->pfn_lo)
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node = node->rb_left;
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else if (pfn > iova->pfn_hi)
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node = node->rb_right;
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else
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return iova; /* pfn falls within iova's range */
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}
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return NULL;
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}
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static void private_free_iova(struct iova_domain *iovad, struct iova *iova)
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{
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assert_spin_locked(&iovad->iova_rbtree_lock);
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__cached_rbnode_delete_update(iovad, iova);
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rb_erase(&iova->node, &iovad->rbroot);
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free_iova_mem(iova);
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}
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/**
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* find_iova - finds an iova for a given pfn
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* @iovad: - iova domain in question.
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* @pfn: - page frame number
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* This function finds and returns an iova belonging to the
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* given doamin which matches the given pfn.
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*/
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struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
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{
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unsigned long flags;
|
|
struct iova *iova;
|
|
|
|
/* Take the lock so that no other thread is manipulating the rbtree */
|
|
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
|
|
iova = private_find_iova(iovad, pfn);
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
return iova;
|
|
}
|
|
EXPORT_SYMBOL_GPL(find_iova);
|
|
|
|
/**
|
|
* __free_iova - frees the given iova
|
|
* @iovad: iova domain in question.
|
|
* @iova: iova in question.
|
|
* Frees the given iova belonging to the giving domain
|
|
*/
|
|
void
|
|
__free_iova(struct iova_domain *iovad, struct iova *iova)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
|
|
private_free_iova(iovad, iova);
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__free_iova);
|
|
|
|
/**
|
|
* free_iova - finds and frees the iova for a given pfn
|
|
* @iovad: - iova domain in question.
|
|
* @pfn: - pfn that is allocated previously
|
|
* This functions finds an iova for a given pfn and then
|
|
* frees the iova from that domain.
|
|
*/
|
|
void
|
|
free_iova(struct iova_domain *iovad, unsigned long pfn)
|
|
{
|
|
struct iova *iova = find_iova(iovad, pfn);
|
|
|
|
if (iova)
|
|
__free_iova(iovad, iova);
|
|
|
|
}
|
|
EXPORT_SYMBOL_GPL(free_iova);
|
|
|
|
/**
|
|
* alloc_iova_fast - allocates an iova from rcache
|
|
* @iovad: - iova domain in question
|
|
* @size: - size of page frames to allocate
|
|
* @limit_pfn: - max limit address
|
|
* @flush_rcache: - set to flush rcache on regular allocation failure
|
|
* This function tries to satisfy an iova allocation from the rcache,
|
|
* and falls back to regular allocation on failure. If regular allocation
|
|
* fails too and the flush_rcache flag is set then the rcache will be flushed.
|
|
*/
|
|
unsigned long
|
|
alloc_iova_fast(struct iova_domain *iovad, unsigned long size,
|
|
unsigned long limit_pfn, bool flush_rcache)
|
|
{
|
|
unsigned long iova_pfn;
|
|
struct iova *new_iova;
|
|
|
|
iova_pfn = iova_rcache_get(iovad, size, limit_pfn + 1);
|
|
if (iova_pfn)
|
|
return iova_pfn;
|
|
|
|
retry:
|
|
new_iova = alloc_iova(iovad, size, limit_pfn, true);
|
|
if (!new_iova) {
|
|
unsigned int cpu;
|
|
|
|
if (!flush_rcache)
|
|
return 0;
|
|
|
|
/* Try replenishing IOVAs by flushing rcache. */
|
|
flush_rcache = false;
|
|
for_each_online_cpu(cpu)
|
|
free_cpu_cached_iovas(cpu, iovad);
|
|
goto retry;
|
|
}
|
|
|
|
return new_iova->pfn_lo;
|
|
}
|
|
EXPORT_SYMBOL_GPL(alloc_iova_fast);
|
|
|
|
/**
|
|
* free_iova_fast - free iova pfn range into rcache
|
|
* @iovad: - iova domain in question.
|
|
* @pfn: - pfn that is allocated previously
|
|
* @size: - # of pages in range
|
|
* This functions frees an iova range by trying to put it into the rcache,
|
|
* falling back to regular iova deallocation via free_iova() if this fails.
|
|
*/
|
|
void
|
|
free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
|
|
{
|
|
if (iova_rcache_insert(iovad, pfn, size))
|
|
return;
|
|
|
|
free_iova(iovad, pfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(free_iova_fast);
|
|
|
|
#define fq_ring_for_each(i, fq) \
|
|
for ((i) = (fq)->head; (i) != (fq)->tail; (i) = ((i) + 1) % IOVA_FQ_SIZE)
|
|
|
|
static inline bool fq_full(struct iova_fq *fq)
|
|
{
|
|
assert_spin_locked(&fq->lock);
|
|
return (((fq->tail + 1) % IOVA_FQ_SIZE) == fq->head);
|
|
}
|
|
|
|
static inline unsigned fq_ring_add(struct iova_fq *fq)
|
|
{
|
|
unsigned idx = fq->tail;
|
|
|
|
assert_spin_locked(&fq->lock);
|
|
|
|
fq->tail = (idx + 1) % IOVA_FQ_SIZE;
|
|
|
|
return idx;
|
|
}
|
|
|
|
static void fq_ring_free(struct iova_domain *iovad, struct iova_fq *fq)
|
|
{
|
|
u64 counter = atomic64_read(&iovad->fq_flush_finish_cnt);
|
|
unsigned idx;
|
|
|
|
assert_spin_locked(&fq->lock);
|
|
|
|
fq_ring_for_each(idx, fq) {
|
|
|
|
if (fq->entries[idx].counter >= counter)
|
|
break;
|
|
|
|
if (iovad->entry_dtor)
|
|
iovad->entry_dtor(fq->entries[idx].data);
|
|
|
|
free_iova_fast(iovad,
|
|
fq->entries[idx].iova_pfn,
|
|
fq->entries[idx].pages);
|
|
|
|
fq->head = (fq->head + 1) % IOVA_FQ_SIZE;
|
|
}
|
|
}
|
|
|
|
static void iova_domain_flush(struct iova_domain *iovad)
|
|
{
|
|
atomic64_inc(&iovad->fq_flush_start_cnt);
|
|
iovad->flush_cb(iovad);
|
|
atomic64_inc(&iovad->fq_flush_finish_cnt);
|
|
}
|
|
|
|
static void fq_destroy_all_entries(struct iova_domain *iovad)
|
|
{
|
|
int cpu;
|
|
|
|
/*
|
|
* This code runs when the iova_domain is being detroyed, so don't
|
|
* bother to free iovas, just call the entry_dtor on all remaining
|
|
* entries.
|
|
*/
|
|
if (!iovad->entry_dtor)
|
|
return;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct iova_fq *fq = per_cpu_ptr(iovad->fq, cpu);
|
|
int idx;
|
|
|
|
fq_ring_for_each(idx, fq)
|
|
iovad->entry_dtor(fq->entries[idx].data);
|
|
}
|
|
}
|
|
|
|
static void fq_flush_timeout(struct timer_list *t)
|
|
{
|
|
struct iova_domain *iovad = from_timer(iovad, t, fq_timer);
|
|
int cpu;
|
|
|
|
atomic_set(&iovad->fq_timer_on, 0);
|
|
iova_domain_flush(iovad);
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
unsigned long flags;
|
|
struct iova_fq *fq;
|
|
|
|
fq = per_cpu_ptr(iovad->fq, cpu);
|
|
spin_lock_irqsave(&fq->lock, flags);
|
|
fq_ring_free(iovad, fq);
|
|
spin_unlock_irqrestore(&fq->lock, flags);
|
|
}
|
|
}
|
|
|
|
void queue_iova(struct iova_domain *iovad,
|
|
unsigned long pfn, unsigned long pages,
|
|
unsigned long data)
|
|
{
|
|
struct iova_fq *fq = raw_cpu_ptr(iovad->fq);
|
|
unsigned long flags;
|
|
unsigned idx;
|
|
|
|
spin_lock_irqsave(&fq->lock, flags);
|
|
|
|
/*
|
|
* First remove all entries from the flush queue that have already been
|
|
* flushed out on another CPU. This makes the fq_full() check below less
|
|
* likely to be true.
|
|
*/
|
|
fq_ring_free(iovad, fq);
|
|
|
|
if (fq_full(fq)) {
|
|
iova_domain_flush(iovad);
|
|
fq_ring_free(iovad, fq);
|
|
}
|
|
|
|
idx = fq_ring_add(fq);
|
|
|
|
fq->entries[idx].iova_pfn = pfn;
|
|
fq->entries[idx].pages = pages;
|
|
fq->entries[idx].data = data;
|
|
fq->entries[idx].counter = atomic64_read(&iovad->fq_flush_start_cnt);
|
|
|
|
spin_unlock_irqrestore(&fq->lock, flags);
|
|
|
|
/* Avoid false sharing as much as possible. */
|
|
if (!atomic_read(&iovad->fq_timer_on) &&
|
|
!atomic_cmpxchg(&iovad->fq_timer_on, 0, 1))
|
|
mod_timer(&iovad->fq_timer,
|
|
jiffies + msecs_to_jiffies(IOVA_FQ_TIMEOUT));
|
|
}
|
|
EXPORT_SYMBOL_GPL(queue_iova);
|
|
|
|
/**
|
|
* put_iova_domain - destroys the iova doamin
|
|
* @iovad: - iova domain in question.
|
|
* All the iova's in that domain are destroyed.
|
|
*/
|
|
void put_iova_domain(struct iova_domain *iovad)
|
|
{
|
|
struct iova *iova, *tmp;
|
|
|
|
free_iova_flush_queue(iovad);
|
|
free_iova_rcaches(iovad);
|
|
rbtree_postorder_for_each_entry_safe(iova, tmp, &iovad->rbroot, node)
|
|
free_iova_mem(iova);
|
|
}
|
|
EXPORT_SYMBOL_GPL(put_iova_domain);
|
|
|
|
static int
|
|
__is_range_overlap(struct rb_node *node,
|
|
unsigned long pfn_lo, unsigned long pfn_hi)
|
|
{
|
|
struct iova *iova = rb_entry(node, struct iova, node);
|
|
|
|
if ((pfn_lo <= iova->pfn_hi) && (pfn_hi >= iova->pfn_lo))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static inline struct iova *
|
|
alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi)
|
|
{
|
|
struct iova *iova;
|
|
|
|
iova = alloc_iova_mem();
|
|
if (iova) {
|
|
iova->pfn_lo = pfn_lo;
|
|
iova->pfn_hi = pfn_hi;
|
|
}
|
|
|
|
return iova;
|
|
}
|
|
|
|
static struct iova *
|
|
__insert_new_range(struct iova_domain *iovad,
|
|
unsigned long pfn_lo, unsigned long pfn_hi)
|
|
{
|
|
struct iova *iova;
|
|
|
|
iova = alloc_and_init_iova(pfn_lo, pfn_hi);
|
|
if (iova)
|
|
iova_insert_rbtree(&iovad->rbroot, iova, NULL);
|
|
|
|
return iova;
|
|
}
|
|
|
|
static void
|
|
__adjust_overlap_range(struct iova *iova,
|
|
unsigned long *pfn_lo, unsigned long *pfn_hi)
|
|
{
|
|
if (*pfn_lo < iova->pfn_lo)
|
|
iova->pfn_lo = *pfn_lo;
|
|
if (*pfn_hi > iova->pfn_hi)
|
|
*pfn_lo = iova->pfn_hi + 1;
|
|
}
|
|
|
|
/**
|
|
* reserve_iova - reserves an iova in the given range
|
|
* @iovad: - iova domain pointer
|
|
* @pfn_lo: - lower page frame address
|
|
* @pfn_hi:- higher pfn adderss
|
|
* This function allocates reserves the address range from pfn_lo to pfn_hi so
|
|
* that this address is not dished out as part of alloc_iova.
|
|
*/
|
|
struct iova *
|
|
reserve_iova(struct iova_domain *iovad,
|
|
unsigned long pfn_lo, unsigned long pfn_hi)
|
|
{
|
|
struct rb_node *node;
|
|
unsigned long flags;
|
|
struct iova *iova;
|
|
unsigned int overlap = 0;
|
|
|
|
/* Don't allow nonsensical pfns */
|
|
if (WARN_ON((pfn_hi | pfn_lo) > (ULLONG_MAX >> iova_shift(iovad))))
|
|
return NULL;
|
|
|
|
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
|
|
for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
|
|
if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
|
|
iova = rb_entry(node, struct iova, node);
|
|
__adjust_overlap_range(iova, &pfn_lo, &pfn_hi);
|
|
if ((pfn_lo >= iova->pfn_lo) &&
|
|
(pfn_hi <= iova->pfn_hi))
|
|
goto finish;
|
|
overlap = 1;
|
|
|
|
} else if (overlap)
|
|
break;
|
|
}
|
|
|
|
/* We are here either because this is the first reserver node
|
|
* or need to insert remaining non overlap addr range
|
|
*/
|
|
iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
|
|
finish:
|
|
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
return iova;
|
|
}
|
|
EXPORT_SYMBOL_GPL(reserve_iova);
|
|
|
|
/**
|
|
* copy_reserved_iova - copies the reserved between domains
|
|
* @from: - source doamin from where to copy
|
|
* @to: - destination domin where to copy
|
|
* This function copies reserved iova's from one doamin to
|
|
* other.
|
|
*/
|
|
void
|
|
copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
|
|
{
|
|
unsigned long flags;
|
|
struct rb_node *node;
|
|
|
|
spin_lock_irqsave(&from->iova_rbtree_lock, flags);
|
|
for (node = rb_first(&from->rbroot); node; node = rb_next(node)) {
|
|
struct iova *iova = rb_entry(node, struct iova, node);
|
|
struct iova *new_iova;
|
|
|
|
if (iova->pfn_lo == IOVA_ANCHOR)
|
|
continue;
|
|
|
|
new_iova = reserve_iova(to, iova->pfn_lo, iova->pfn_hi);
|
|
if (!new_iova)
|
|
printk(KERN_ERR "Reserve iova range %lx@%lx failed\n",
|
|
iova->pfn_lo, iova->pfn_lo);
|
|
}
|
|
spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(copy_reserved_iova);
|
|
|
|
struct iova *
|
|
split_and_remove_iova(struct iova_domain *iovad, struct iova *iova,
|
|
unsigned long pfn_lo, unsigned long pfn_hi)
|
|
{
|
|
unsigned long flags;
|
|
struct iova *prev = NULL, *next = NULL;
|
|
|
|
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
|
|
if (iova->pfn_lo < pfn_lo) {
|
|
prev = alloc_and_init_iova(iova->pfn_lo, pfn_lo - 1);
|
|
if (prev == NULL)
|
|
goto error;
|
|
}
|
|
if (iova->pfn_hi > pfn_hi) {
|
|
next = alloc_and_init_iova(pfn_hi + 1, iova->pfn_hi);
|
|
if (next == NULL)
|
|
goto error;
|
|
}
|
|
|
|
__cached_rbnode_delete_update(iovad, iova);
|
|
rb_erase(&iova->node, &iovad->rbroot);
|
|
|
|
if (prev) {
|
|
iova_insert_rbtree(&iovad->rbroot, prev, NULL);
|
|
iova->pfn_lo = pfn_lo;
|
|
}
|
|
if (next) {
|
|
iova_insert_rbtree(&iovad->rbroot, next, NULL);
|
|
iova->pfn_hi = pfn_hi;
|
|
}
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
|
|
return iova;
|
|
|
|
error:
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
if (prev)
|
|
free_iova_mem(prev);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Magazine caches for IOVA ranges. For an introduction to magazines,
|
|
* see the USENIX 2001 paper "Magazines and Vmem: Extending the Slab
|
|
* Allocator to Many CPUs and Arbitrary Resources" by Bonwick and Adams.
|
|
* For simplicity, we use a static magazine size and don't implement the
|
|
* dynamic size tuning described in the paper.
|
|
*/
|
|
|
|
#define IOVA_MAG_SIZE 128
|
|
|
|
struct iova_magazine {
|
|
unsigned long size;
|
|
unsigned long pfns[IOVA_MAG_SIZE];
|
|
};
|
|
|
|
struct iova_cpu_rcache {
|
|
spinlock_t lock;
|
|
struct iova_magazine *loaded;
|
|
struct iova_magazine *prev;
|
|
};
|
|
|
|
static struct iova_magazine *iova_magazine_alloc(gfp_t flags)
|
|
{
|
|
return kzalloc(sizeof(struct iova_magazine), flags);
|
|
}
|
|
|
|
static void iova_magazine_free(struct iova_magazine *mag)
|
|
{
|
|
kfree(mag);
|
|
}
|
|
|
|
static void
|
|
iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad)
|
|
{
|
|
unsigned long flags;
|
|
int i;
|
|
|
|
if (!mag)
|
|
return;
|
|
|
|
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
|
|
|
|
for (i = 0 ; i < mag->size; ++i) {
|
|
struct iova *iova = private_find_iova(iovad, mag->pfns[i]);
|
|
|
|
BUG_ON(!iova);
|
|
private_free_iova(iovad, iova);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
|
|
|
|
mag->size = 0;
|
|
}
|
|
|
|
static bool iova_magazine_full(struct iova_magazine *mag)
|
|
{
|
|
return (mag && mag->size == IOVA_MAG_SIZE);
|
|
}
|
|
|
|
static bool iova_magazine_empty(struct iova_magazine *mag)
|
|
{
|
|
return (!mag || mag->size == 0);
|
|
}
|
|
|
|
static unsigned long iova_magazine_pop(struct iova_magazine *mag,
|
|
unsigned long limit_pfn)
|
|
{
|
|
int i;
|
|
unsigned long pfn;
|
|
|
|
BUG_ON(iova_magazine_empty(mag));
|
|
|
|
/* Only fall back to the rbtree if we have no suitable pfns at all */
|
|
for (i = mag->size - 1; mag->pfns[i] > limit_pfn; i--)
|
|
if (i == 0)
|
|
return 0;
|
|
|
|
/* Swap it to pop it */
|
|
pfn = mag->pfns[i];
|
|
mag->pfns[i] = mag->pfns[--mag->size];
|
|
|
|
return pfn;
|
|
}
|
|
|
|
static void iova_magazine_push(struct iova_magazine *mag, unsigned long pfn)
|
|
{
|
|
BUG_ON(iova_magazine_full(mag));
|
|
|
|
mag->pfns[mag->size++] = pfn;
|
|
}
|
|
|
|
static void init_iova_rcaches(struct iova_domain *iovad)
|
|
{
|
|
struct iova_cpu_rcache *cpu_rcache;
|
|
struct iova_rcache *rcache;
|
|
unsigned int cpu;
|
|
int i;
|
|
|
|
for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
|
|
rcache = &iovad->rcaches[i];
|
|
spin_lock_init(&rcache->lock);
|
|
rcache->depot_size = 0;
|
|
rcache->cpu_rcaches = __alloc_percpu(sizeof(*cpu_rcache), cache_line_size());
|
|
if (WARN_ON(!rcache->cpu_rcaches))
|
|
continue;
|
|
for_each_possible_cpu(cpu) {
|
|
cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
|
|
spin_lock_init(&cpu_rcache->lock);
|
|
cpu_rcache->loaded = iova_magazine_alloc(GFP_KERNEL);
|
|
cpu_rcache->prev = iova_magazine_alloc(GFP_KERNEL);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Try inserting IOVA range starting with 'iova_pfn' into 'rcache', and
|
|
* return true on success. Can fail if rcache is full and we can't free
|
|
* space, and free_iova() (our only caller) will then return the IOVA
|
|
* range to the rbtree instead.
|
|
*/
|
|
static bool __iova_rcache_insert(struct iova_domain *iovad,
|
|
struct iova_rcache *rcache,
|
|
unsigned long iova_pfn)
|
|
{
|
|
struct iova_magazine *mag_to_free = NULL;
|
|
struct iova_cpu_rcache *cpu_rcache;
|
|
bool can_insert = false;
|
|
unsigned long flags;
|
|
|
|
cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
|
|
spin_lock_irqsave(&cpu_rcache->lock, flags);
|
|
|
|
if (!iova_magazine_full(cpu_rcache->loaded)) {
|
|
can_insert = true;
|
|
} else if (!iova_magazine_full(cpu_rcache->prev)) {
|
|
swap(cpu_rcache->prev, cpu_rcache->loaded);
|
|
can_insert = true;
|
|
} else {
|
|
struct iova_magazine *new_mag = iova_magazine_alloc(GFP_ATOMIC);
|
|
|
|
if (new_mag) {
|
|
spin_lock(&rcache->lock);
|
|
if (rcache->depot_size < MAX_GLOBAL_MAGS) {
|
|
rcache->depot[rcache->depot_size++] =
|
|
cpu_rcache->loaded;
|
|
} else {
|
|
mag_to_free = cpu_rcache->loaded;
|
|
}
|
|
spin_unlock(&rcache->lock);
|
|
|
|
cpu_rcache->loaded = new_mag;
|
|
can_insert = true;
|
|
}
|
|
}
|
|
|
|
if (can_insert)
|
|
iova_magazine_push(cpu_rcache->loaded, iova_pfn);
|
|
|
|
spin_unlock_irqrestore(&cpu_rcache->lock, flags);
|
|
|
|
if (mag_to_free) {
|
|
iova_magazine_free_pfns(mag_to_free, iovad);
|
|
iova_magazine_free(mag_to_free);
|
|
}
|
|
|
|
return can_insert;
|
|
}
|
|
|
|
static bool iova_rcache_insert(struct iova_domain *iovad, unsigned long pfn,
|
|
unsigned long size)
|
|
{
|
|
unsigned int log_size = order_base_2(size);
|
|
|
|
if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
|
|
return false;
|
|
|
|
return __iova_rcache_insert(iovad, &iovad->rcaches[log_size], pfn);
|
|
}
|
|
|
|
/*
|
|
* Caller wants to allocate a new IOVA range from 'rcache'. If we can
|
|
* satisfy the request, return a matching non-NULL range and remove
|
|
* it from the 'rcache'.
|
|
*/
|
|
static unsigned long __iova_rcache_get(struct iova_rcache *rcache,
|
|
unsigned long limit_pfn)
|
|
{
|
|
struct iova_cpu_rcache *cpu_rcache;
|
|
unsigned long iova_pfn = 0;
|
|
bool has_pfn = false;
|
|
unsigned long flags;
|
|
|
|
cpu_rcache = raw_cpu_ptr(rcache->cpu_rcaches);
|
|
spin_lock_irqsave(&cpu_rcache->lock, flags);
|
|
|
|
if (!iova_magazine_empty(cpu_rcache->loaded)) {
|
|
has_pfn = true;
|
|
} else if (!iova_magazine_empty(cpu_rcache->prev)) {
|
|
swap(cpu_rcache->prev, cpu_rcache->loaded);
|
|
has_pfn = true;
|
|
} else {
|
|
spin_lock(&rcache->lock);
|
|
if (rcache->depot_size > 0) {
|
|
iova_magazine_free(cpu_rcache->loaded);
|
|
cpu_rcache->loaded = rcache->depot[--rcache->depot_size];
|
|
has_pfn = true;
|
|
}
|
|
spin_unlock(&rcache->lock);
|
|
}
|
|
|
|
if (has_pfn)
|
|
iova_pfn = iova_magazine_pop(cpu_rcache->loaded, limit_pfn);
|
|
|
|
spin_unlock_irqrestore(&cpu_rcache->lock, flags);
|
|
|
|
return iova_pfn;
|
|
}
|
|
|
|
/*
|
|
* Try to satisfy IOVA allocation range from rcache. Fail if requested
|
|
* size is too big or the DMA limit we are given isn't satisfied by the
|
|
* top element in the magazine.
|
|
*/
|
|
static unsigned long iova_rcache_get(struct iova_domain *iovad,
|
|
unsigned long size,
|
|
unsigned long limit_pfn)
|
|
{
|
|
unsigned int log_size = order_base_2(size);
|
|
|
|
if (log_size >= IOVA_RANGE_CACHE_MAX_SIZE)
|
|
return 0;
|
|
|
|
return __iova_rcache_get(&iovad->rcaches[log_size], limit_pfn - size);
|
|
}
|
|
|
|
/*
|
|
* free rcache data structures.
|
|
*/
|
|
static void free_iova_rcaches(struct iova_domain *iovad)
|
|
{
|
|
struct iova_rcache *rcache;
|
|
struct iova_cpu_rcache *cpu_rcache;
|
|
unsigned int cpu;
|
|
int i, j;
|
|
|
|
for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
|
|
rcache = &iovad->rcaches[i];
|
|
for_each_possible_cpu(cpu) {
|
|
cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
|
|
iova_magazine_free(cpu_rcache->loaded);
|
|
iova_magazine_free(cpu_rcache->prev);
|
|
}
|
|
free_percpu(rcache->cpu_rcaches);
|
|
for (j = 0; j < rcache->depot_size; ++j)
|
|
iova_magazine_free(rcache->depot[j]);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* free all the IOVA ranges cached by a cpu (used when cpu is unplugged)
|
|
*/
|
|
void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad)
|
|
{
|
|
struct iova_cpu_rcache *cpu_rcache;
|
|
struct iova_rcache *rcache;
|
|
unsigned long flags;
|
|
int i;
|
|
|
|
for (i = 0; i < IOVA_RANGE_CACHE_MAX_SIZE; ++i) {
|
|
rcache = &iovad->rcaches[i];
|
|
cpu_rcache = per_cpu_ptr(rcache->cpu_rcaches, cpu);
|
|
spin_lock_irqsave(&cpu_rcache->lock, flags);
|
|
iova_magazine_free_pfns(cpu_rcache->loaded, iovad);
|
|
iova_magazine_free_pfns(cpu_rcache->prev, iovad);
|
|
spin_unlock_irqrestore(&cpu_rcache->lock, flags);
|
|
}
|
|
}
|
|
|
|
MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>");
|
|
MODULE_LICENSE("GPL");
|