blob: b40a4678c29639c3090be39e64033a46c61ed138 [file] [log] [blame]
/*
* Copyright (c) Red Hat Inc.
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sub license,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Authors: Dave Airlie <airlied@redhat.com>
* Jerome Glisse <jglisse@redhat.com>
* Pauli Nieminen <suokkos@gmail.com>
*/
/* simple list based uncached page pool
* - Pool collects resently freed pages for reuse
* - Use page->lru to keep a free list
* - doesn't track currently in use pages
*/
#define pr_fmt(fmt) "[TTM] " fmt
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/highmem.h>
#include <linux/mm_types.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/seq_file.h> /* for seq_printf */
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/atomic.h>
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_page_alloc.h>
#include <drm/ttm/ttm_set_memory.h>
#define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *))
#define SMALL_ALLOCATION 16
#define FREE_ALL_PAGES (~0U)
/* times are in msecs */
#define PAGE_FREE_INTERVAL 1000
/**
* struct ttm_page_pool - Pool to reuse recently allocated uc/wc pages.
*
* @lock: Protects the shared pool from concurrnet access. Must be used with
* irqsave/irqrestore variants because pool allocator maybe called from
* delayed work.
* @fill_lock: Prevent concurrent calls to fill.
* @list: Pool of free uc/wc pages for fast reuse.
* @gfp_flags: Flags to pass for alloc_page.
* @npages: Number of pages in pool.
*/
struct ttm_page_pool {
spinlock_t lock;
bool fill_lock;
struct list_head list;
gfp_t gfp_flags;
unsigned npages;
char *name;
unsigned long nfrees;
unsigned long nrefills;
unsigned int order;
};
/**
* Limits for the pool. They are handled without locks because only place where
* they may change is in sysfs store. They won't have immediate effect anyway
* so forcing serialization to access them is pointless.
*/
struct ttm_pool_opts {
unsigned alloc_size;
unsigned max_size;
unsigned small;
};
#define NUM_POOLS 6
/**
* struct ttm_pool_manager - Holds memory pools for fst allocation
*
* Manager is read only object for pool code so it doesn't need locking.
*
* @free_interval: minimum number of jiffies between freeing pages from pool.
* @page_alloc_inited: reference counting for pool allocation.
* @work: Work that is used to shrink the pool. Work is only run when there is
* some pages to free.
* @small_allocation: Limit in number of pages what is small allocation.
*
* @pools: All pool objects in use.
**/
struct ttm_pool_manager {
struct kobject kobj;
struct shrinker mm_shrink;
struct ttm_pool_opts options;
union {
struct ttm_page_pool pools[NUM_POOLS];
struct {
struct ttm_page_pool wc_pool;
struct ttm_page_pool uc_pool;
struct ttm_page_pool wc_pool_dma32;
struct ttm_page_pool uc_pool_dma32;
struct ttm_page_pool wc_pool_huge;
struct ttm_page_pool uc_pool_huge;
} ;
};
};
static struct attribute ttm_page_pool_max = {
.name = "pool_max_size",
.mode = S_IRUGO | S_IWUSR
};
static struct attribute ttm_page_pool_small = {
.name = "pool_small_allocation",
.mode = S_IRUGO | S_IWUSR
};
static struct attribute ttm_page_pool_alloc_size = {
.name = "pool_allocation_size",
.mode = S_IRUGO | S_IWUSR
};
static struct attribute *ttm_pool_attrs[] = {
&ttm_page_pool_max,
&ttm_page_pool_small,
&ttm_page_pool_alloc_size,
NULL
};
static void ttm_pool_kobj_release(struct kobject *kobj)
{
struct ttm_pool_manager *m =
container_of(kobj, struct ttm_pool_manager, kobj);
kfree(m);
}
static ssize_t ttm_pool_store(struct kobject *kobj,
struct attribute *attr, const char *buffer, size_t size)
{
struct ttm_pool_manager *m =
container_of(kobj, struct ttm_pool_manager, kobj);
int chars;
unsigned val;
chars = sscanf(buffer, "%u", &val);
if (chars == 0)
return size;
/* Convert kb to number of pages */
val = val / (PAGE_SIZE >> 10);
if (attr == &ttm_page_pool_max)
m->options.max_size = val;
else if (attr == &ttm_page_pool_small)
m->options.small = val;
else if (attr == &ttm_page_pool_alloc_size) {
if (val > NUM_PAGES_TO_ALLOC*8) {
pr_err("Setting allocation size to %lu is not allowed. Recommended size is %lu\n",
NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 7),
NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10));
return size;
} else if (val > NUM_PAGES_TO_ALLOC) {
pr_warn("Setting allocation size to larger than %lu is not recommended\n",
NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10));
}
m->options.alloc_size = val;
}
return size;
}
static ssize_t ttm_pool_show(struct kobject *kobj,
struct attribute *attr, char *buffer)
{
struct ttm_pool_manager *m =
container_of(kobj, struct ttm_pool_manager, kobj);
unsigned val = 0;
if (attr == &ttm_page_pool_max)
val = m->options.max_size;
else if (attr == &ttm_page_pool_small)
val = m->options.small;
else if (attr == &ttm_page_pool_alloc_size)
val = m->options.alloc_size;
val = val * (PAGE_SIZE >> 10);
return snprintf(buffer, PAGE_SIZE, "%u\n", val);
}
static const struct sysfs_ops ttm_pool_sysfs_ops = {
.show = &ttm_pool_show,
.store = &ttm_pool_store,
};
static struct kobj_type ttm_pool_kobj_type = {
.release = &ttm_pool_kobj_release,
.sysfs_ops = &ttm_pool_sysfs_ops,
.default_attrs = ttm_pool_attrs,
};
static struct ttm_pool_manager *_manager;
/**
* Select the right pool or requested caching state and ttm flags. */
static struct ttm_page_pool *ttm_get_pool(int flags, bool huge,
enum ttm_caching_state cstate)
{
int pool_index;
if (cstate == tt_cached)
return NULL;
if (cstate == tt_wc)
pool_index = 0x0;
else
pool_index = 0x1;
if (flags & TTM_PAGE_FLAG_DMA32) {
if (huge)
return NULL;
pool_index |= 0x2;
} else if (huge) {
pool_index |= 0x4;
}
return &_manager->pools[pool_index];
}
/* set memory back to wb and free the pages. */
static void ttm_pages_put(struct page *pages[], unsigned npages,
unsigned int order)
{
unsigned int i, pages_nr = (1 << order);
if (order == 0) {
if (ttm_set_pages_array_wb(pages, npages))
pr_err("Failed to set %d pages to wb!\n", npages);
}
for (i = 0; i < npages; ++i) {
if (order > 0) {
if (ttm_set_pages_wb(pages[i], pages_nr))
pr_err("Failed to set %d pages to wb!\n", pages_nr);
}
__free_pages(pages[i], order);
}
}
static void ttm_pool_update_free_locked(struct ttm_page_pool *pool,
unsigned freed_pages)
{
pool->npages -= freed_pages;
pool->nfrees += freed_pages;
}
/**
* Free pages from pool.
*
* To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC
* number of pages in one go.
*
* @pool: to free the pages from
* @free_all: If set to true will free all pages in pool
* @use_static: Safe to use static buffer
**/
static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free,
bool use_static)
{
static struct page *static_buf[NUM_PAGES_TO_ALLOC];
unsigned long irq_flags;
struct page *p;
struct page **pages_to_free;
unsigned freed_pages = 0,
npages_to_free = nr_free;
if (NUM_PAGES_TO_ALLOC < nr_free)
npages_to_free = NUM_PAGES_TO_ALLOC;
if (use_static)
pages_to_free = static_buf;
else
pages_to_free = kmalloc_array(npages_to_free,
sizeof(struct page *),
GFP_KERNEL);
if (!pages_to_free) {
pr_debug("Failed to allocate memory for pool free operation\n");
return 0;
}
restart:
spin_lock_irqsave(&pool->lock, irq_flags);
list_for_each_entry_reverse(p, &pool->list, lru) {
if (freed_pages >= npages_to_free)
break;
pages_to_free[freed_pages++] = p;
/* We can only remove NUM_PAGES_TO_ALLOC at a time. */
if (freed_pages >= NUM_PAGES_TO_ALLOC) {
/* remove range of pages from the pool */
__list_del(p->lru.prev, &pool->list);
ttm_pool_update_free_locked(pool, freed_pages);
/**
* Because changing page caching is costly
* we unlock the pool to prevent stalling.
*/
spin_unlock_irqrestore(&pool->lock, irq_flags);
ttm_pages_put(pages_to_free, freed_pages, pool->order);
if (likely(nr_free != FREE_ALL_PAGES))
nr_free -= freed_pages;
if (NUM_PAGES_TO_ALLOC >= nr_free)
npages_to_free = nr_free;
else
npages_to_free = NUM_PAGES_TO_ALLOC;
freed_pages = 0;
/* free all so restart the processing */
if (nr_free)
goto restart;
/* Not allowed to fall through or break because
* following context is inside spinlock while we are
* outside here.
*/
goto out;
}
}
/* remove range of pages from the pool */
if (freed_pages) {
__list_del(&p->lru, &pool->list);
ttm_pool_update_free_locked(pool, freed_pages);
nr_free -= freed_pages;
}
spin_unlock_irqrestore(&pool->lock, irq_flags);
if (freed_pages)
ttm_pages_put(pages_to_free, freed_pages, pool->order);
out:
if (pages_to_free != static_buf)
kfree(pages_to_free);
return nr_free;
}
/**
* Callback for mm to request pool to reduce number of page held.
*
* XXX: (dchinner) Deadlock warning!
*
* This code is crying out for a shrinker per pool....
*/
static unsigned long
ttm_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
{
static DEFINE_MUTEX(lock);
static unsigned start_pool;
unsigned i;
unsigned pool_offset;
struct ttm_page_pool *pool;
int shrink_pages = sc->nr_to_scan;
unsigned long freed = 0;
unsigned int nr_free_pool;
if (!mutex_trylock(&lock))
return SHRINK_STOP;
pool_offset = ++start_pool % NUM_POOLS;
/* select start pool in round robin fashion */
for (i = 0; i < NUM_POOLS; ++i) {
unsigned nr_free = shrink_pages;
unsigned page_nr;
if (shrink_pages == 0)
break;
pool = &_manager->pools[(i + pool_offset)%NUM_POOLS];
page_nr = (1 << pool->order);
/* OK to use static buffer since global mutex is held. */
nr_free_pool = roundup(nr_free, page_nr) >> pool->order;
shrink_pages = ttm_page_pool_free(pool, nr_free_pool, true);
freed += (nr_free_pool - shrink_pages) << pool->order;
if (freed >= sc->nr_to_scan)
break;
shrink_pages <<= pool->order;
}
mutex_unlock(&lock);
return freed;
}
static unsigned long
ttm_pool_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
{
unsigned i;
unsigned long count = 0;
struct ttm_page_pool *pool;
for (i = 0; i < NUM_POOLS; ++i) {
pool = &_manager->pools[i];
count += (pool->npages << pool->order);
}
return count;
}
static int ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager)
{
manager->mm_shrink.count_objects = ttm_pool_shrink_count;
manager->mm_shrink.scan_objects = ttm_pool_shrink_scan;
manager->mm_shrink.seeks = 1;
return register_shrinker(&manager->mm_shrink);
}
static void ttm_pool_mm_shrink_fini(struct ttm_pool_manager *manager)
{
unregister_shrinker(&manager->mm_shrink);
}
static int ttm_set_pages_caching(struct page **pages,
enum ttm_caching_state cstate, unsigned cpages)
{
int r = 0;
/* Set page caching */
switch (cstate) {
case tt_uncached:
r = ttm_set_pages_array_uc(pages, cpages);
if (r)
pr_err("Failed to set %d pages to uc!\n", cpages);
break;
case tt_wc:
r = ttm_set_pages_array_wc(pages, cpages);
if (r)
pr_err("Failed to set %d pages to wc!\n", cpages);
break;
default:
break;
}
return r;
}
/**
* Free pages the pages that failed to change the caching state. If there is
* any pages that have changed their caching state already put them to the
* pool.
*/
static void ttm_handle_caching_state_failure(struct list_head *pages,
int ttm_flags, enum ttm_caching_state cstate,
struct page **failed_pages, unsigned cpages)
{
unsigned i;
/* Failed pages have to be freed */
for (i = 0; i < cpages; ++i) {
list_del(&failed_pages[i]->lru);
__free_page(failed_pages[i]);
}
}
/**
* Allocate new pages with correct caching.
*
* This function is reentrant if caller updates count depending on number of
* pages returned in pages array.
*/
static int ttm_alloc_new_pages(struct list_head *pages, gfp_t gfp_flags,
int ttm_flags, enum ttm_caching_state cstate,
unsigned count, unsigned order)
{
struct page **caching_array;
struct page *p;
int r = 0;
unsigned i, j, cpages;
unsigned npages = 1 << order;
unsigned max_cpages = min(count << order, (unsigned)NUM_PAGES_TO_ALLOC);
/* allocate array for page caching change */
caching_array = kmalloc_array(max_cpages, sizeof(struct page *),
GFP_KERNEL);
if (!caching_array) {
pr_debug("Unable to allocate table for new pages\n");
return -ENOMEM;
}
for (i = 0, cpages = 0; i < count; ++i) {
p = alloc_pages(gfp_flags, order);
if (!p) {
pr_debug("Unable to get page %u\n", i);
/* store already allocated pages in the pool after
* setting the caching state */
if (cpages) {
r = ttm_set_pages_caching(caching_array,
cstate, cpages);
if (r)
ttm_handle_caching_state_failure(pages,
ttm_flags, cstate,
caching_array, cpages);
}
r = -ENOMEM;
goto out;
}
list_add(&p->lru, pages);
#ifdef CONFIG_HIGHMEM
/* gfp flags of highmem page should never be dma32 so we
* we should be fine in such case
*/
if (PageHighMem(p))
continue;
#endif
for (j = 0; j < npages; ++j) {
caching_array[cpages++] = p++;
if (cpages == max_cpages) {
r = ttm_set_pages_caching(caching_array,
cstate, cpages);
if (r) {
ttm_handle_caching_state_failure(pages,
ttm_flags, cstate,
caching_array, cpages);
goto out;
}
cpages = 0;
}
}
}
if (cpages) {
r = ttm_set_pages_caching(caching_array, cstate, cpages);
if (r)
ttm_handle_caching_state_failure(pages,
ttm_flags, cstate,
caching_array, cpages);
}
out:
kfree(caching_array);
return r;
}
/**
* Fill the given pool if there aren't enough pages and the requested number of
* pages is small.
*/
static void ttm_page_pool_fill_locked(struct ttm_page_pool *pool, int ttm_flags,
enum ttm_caching_state cstate,
unsigned count, unsigned long *irq_flags)
{
struct page *p;
int r;
unsigned cpages = 0;
/**
* Only allow one pool fill operation at a time.
* If pool doesn't have enough pages for the allocation new pages are
* allocated from outside of pool.
*/
if (pool->fill_lock)
return;
pool->fill_lock = true;
/* If allocation request is small and there are not enough
* pages in a pool we fill the pool up first. */
if (count < _manager->options.small
&& count > pool->npages) {
struct list_head new_pages;
unsigned alloc_size = _manager->options.alloc_size;
/**
* Can't change page caching if in irqsave context. We have to
* drop the pool->lock.
*/
spin_unlock_irqrestore(&pool->lock, *irq_flags);
INIT_LIST_HEAD(&new_pages);
r = ttm_alloc_new_pages(&new_pages, pool->gfp_flags, ttm_flags,
cstate, alloc_size, 0);
spin_lock_irqsave(&pool->lock, *irq_flags);
if (!r) {
list_splice(&new_pages, &pool->list);
++pool->nrefills;
pool->npages += alloc_size;
} else {
pr_debug("Failed to fill pool (%p)\n", pool);
/* If we have any pages left put them to the pool. */
list_for_each_entry(p, &new_pages, lru) {
++cpages;
}
list_splice(&new_pages, &pool->list);
pool->npages += cpages;
}
}
pool->fill_lock = false;
}
/**
* Allocate pages from the pool and put them on the return list.
*
* @return zero for success or negative error code.
*/
static int ttm_page_pool_get_pages(struct ttm_page_pool *pool,
struct list_head *pages,
int ttm_flags,
enum ttm_caching_state cstate,
unsigned count, unsigned order)
{
unsigned long irq_flags;
struct list_head *p;
unsigned i;
int r = 0;
spin_lock_irqsave(&pool->lock, irq_flags);
if (!order)
ttm_page_pool_fill_locked(pool, ttm_flags, cstate, count,
&irq_flags);
if (count >= pool->npages) {
/* take all pages from the pool */
list_splice_init(&pool->list, pages);
count -= pool->npages;
pool->npages = 0;
goto out;
}
/* find the last pages to include for requested number of pages. Split
* pool to begin and halve it to reduce search space. */
if (count <= pool->npages/2) {
i = 0;
list_for_each(p, &pool->list) {
if (++i == count)
break;
}
} else {
i = pool->npages + 1;
list_for_each_prev(p, &pool->list) {
if (--i == count)
break;
}
}
/* Cut 'count' number of pages from the pool */
list_cut_position(pages, &pool->list, p);
pool->npages -= count;
count = 0;
out:
spin_unlock_irqrestore(&pool->lock, irq_flags);
/* clear the pages coming from the pool if requested */
if (ttm_flags & TTM_PAGE_FLAG_ZERO_ALLOC) {
struct page *page;
list_for_each_entry(page, pages, lru) {
if (PageHighMem(page))
clear_highpage(page);
else
clear_page(page_address(page));
}
}
/* If pool didn't have enough pages allocate new one. */
if (count) {
gfp_t gfp_flags = pool->gfp_flags;
/* set zero flag for page allocation if required */
if (ttm_flags & TTM_PAGE_FLAG_ZERO_ALLOC)
gfp_flags |= __GFP_ZERO;
if (ttm_flags & TTM_PAGE_FLAG_NO_RETRY)
gfp_flags |= __GFP_RETRY_MAYFAIL;
/* ttm_alloc_new_pages doesn't reference pool so we can run
* multiple requests in parallel.
**/
r = ttm_alloc_new_pages(pages, gfp_flags, ttm_flags, cstate,
count, order);
}
return r;
}
/* Put all pages in pages list to correct pool to wait for reuse */
static void ttm_put_pages(struct page **pages, unsigned npages, int flags,
enum ttm_caching_state cstate)
{
struct ttm_page_pool *pool = ttm_get_pool(flags, false, cstate);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
struct ttm_page_pool *huge = ttm_get_pool(flags, true, cstate);
#endif
unsigned long irq_flags;
unsigned i;
if (pool == NULL) {
/* No pool for this memory type so free the pages */
i = 0;
while (i < npages) {
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
struct page *p = pages[i];
#endif
unsigned order = 0, j;
if (!pages[i]) {
++i;
continue;
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (!(flags & TTM_PAGE_FLAG_DMA32) &&
(npages - i) >= HPAGE_PMD_NR) {
for (j = 1; j < HPAGE_PMD_NR; ++j)
if (++p != pages[i + j])
break;
if (j == HPAGE_PMD_NR)
order = HPAGE_PMD_ORDER;
}
#endif
if (page_count(pages[i]) != 1)
pr_err("Erroneous page count. Leaking pages.\n");
__free_pages(pages[i], order);
j = 1 << order;
while (j) {
pages[i++] = NULL;
--j;
}
}
return;
}
i = 0;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (huge) {
unsigned max_size, n2free;
spin_lock_irqsave(&huge->lock, irq_flags);
while ((npages - i) >= HPAGE_PMD_NR) {
struct page *p = pages[i];
unsigned j;
if (!p)
break;
for (j = 1; j < HPAGE_PMD_NR; ++j)
if (++p != pages[i + j])
break;
if (j != HPAGE_PMD_NR)
break;
list_add_tail(&pages[i]->lru, &huge->list);
for (j = 0; j < HPAGE_PMD_NR; ++j)
pages[i++] = NULL;
huge->npages++;
}
/* Check that we don't go over the pool limit */
max_size = _manager->options.max_size;
max_size /= HPAGE_PMD_NR;
if (huge->npages > max_size)
n2free = huge->npages - max_size;
else
n2free = 0;
spin_unlock_irqrestore(&huge->lock, irq_flags);
if (n2free)
ttm_page_pool_free(huge, n2free, false);
}
#endif
spin_lock_irqsave(&pool->lock, irq_flags);
while (i < npages) {
if (pages[i]) {
if (page_count(pages[i]) != 1)
pr_err("Erroneous page count. Leaking pages.\n");
list_add_tail(&pages[i]->lru, &pool->list);
pages[i] = NULL;
pool->npages++;
}
++i;
}
/* Check that we don't go over the pool limit */
npages = 0;
if (pool->npages > _manager->options.max_size) {
npages = pool->npages - _manager->options.max_size;
/* free at least NUM_PAGES_TO_ALLOC number of pages
* to reduce calls to set_memory_wb */
if (npages < NUM_PAGES_TO_ALLOC)
npages = NUM_PAGES_TO_ALLOC;
}
spin_unlock_irqrestore(&pool->lock, irq_flags);
if (npages)
ttm_page_pool_free(pool, npages, false);
}
/*
* On success pages list will hold count number of correctly
* cached pages.
*/
static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
enum ttm_caching_state cstate)
{
struct ttm_page_pool *pool = ttm_get_pool(flags, false, cstate);
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
struct ttm_page_pool *huge = ttm_get_pool(flags, true, cstate);
#endif
struct list_head plist;
struct page *p = NULL;
unsigned count, first;
int r;
/* No pool for cached pages */
if (pool == NULL) {
gfp_t gfp_flags = GFP_USER;
unsigned i;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
unsigned j;
#endif
/* set zero flag for page allocation if required */
if (flags & TTM_PAGE_FLAG_ZERO_ALLOC)
gfp_flags |= __GFP_ZERO;
if (flags & TTM_PAGE_FLAG_NO_RETRY)
gfp_flags |= __GFP_RETRY_MAYFAIL;
if (flags & TTM_PAGE_FLAG_DMA32)
gfp_flags |= GFP_DMA32;
else
gfp_flags |= GFP_HIGHUSER;
i = 0;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (!(gfp_flags & GFP_DMA32)) {
while (npages >= HPAGE_PMD_NR) {
gfp_t huge_flags = gfp_flags;
huge_flags |= GFP_TRANSHUGE_LIGHT | __GFP_NORETRY |
__GFP_KSWAPD_RECLAIM;
huge_flags &= ~__GFP_MOVABLE;
huge_flags &= ~__GFP_COMP;
p = alloc_pages(huge_flags, HPAGE_PMD_ORDER);
if (!p)
break;
for (j = 0; j < HPAGE_PMD_NR; ++j)
pages[i++] = p++;
npages -= HPAGE_PMD_NR;
}
}
#endif
first = i;
while (npages) {
p = alloc_page(gfp_flags);
if (!p) {
pr_debug("Unable to allocate page\n");
return -ENOMEM;
}
/* Swap the pages if we detect consecutive order */
if (i > first && pages[i - 1] == p - 1)
swap(p, pages[i - 1]);
pages[i++] = p;
--npages;
}
return 0;
}
count = 0;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (huge && npages >= HPAGE_PMD_NR) {
INIT_LIST_HEAD(&plist);
ttm_page_pool_get_pages(huge, &plist, flags, cstate,
npages / HPAGE_PMD_NR,
HPAGE_PMD_ORDER);
list_for_each_entry(p, &plist, lru) {
unsigned j;
for (j = 0; j < HPAGE_PMD_NR; ++j)
pages[count++] = &p[j];
}
}
#endif
INIT_LIST_HEAD(&plist);
r = ttm_page_pool_get_pages(pool, &plist, flags, cstate,
npages - count, 0);
first = count;
list_for_each_entry(p, &plist, lru) {
struct page *tmp = p;
/* Swap the pages if we detect consecutive order */
if (count > first && pages[count - 1] == tmp - 1)
swap(tmp, pages[count - 1]);
pages[count++] = tmp;
}
if (r) {
/* If there is any pages in the list put them back to
* the pool.
*/
pr_debug("Failed to allocate extra pages for large request\n");
ttm_put_pages(pages, count, flags, cstate);
return r;
}
return 0;
}
static void ttm_page_pool_init_locked(struct ttm_page_pool *pool, gfp_t flags,
char *name, unsigned int order)
{
spin_lock_init(&pool->lock);
pool->fill_lock = false;
INIT_LIST_HEAD(&pool->list);
pool->npages = pool->nfrees = 0;
pool->gfp_flags = flags;
pool->name = name;
pool->order = order;
}
int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
{
int ret;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
unsigned order = HPAGE_PMD_ORDER;
#else
unsigned order = 0;
#endif
WARN_ON(_manager);
pr_info("Initializing pool allocator\n");
_manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
if (!_manager)
return -ENOMEM;
ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc", 0);
ttm_page_pool_init_locked(&_manager->uc_pool, GFP_HIGHUSER, "uc", 0);
ttm_page_pool_init_locked(&_manager->wc_pool_dma32,
GFP_USER | GFP_DMA32, "wc dma", 0);
ttm_page_pool_init_locked(&_manager->uc_pool_dma32,
GFP_USER | GFP_DMA32, "uc dma", 0);
ttm_page_pool_init_locked(&_manager->wc_pool_huge,
(GFP_TRANSHUGE_LIGHT | __GFP_NORETRY |
__GFP_KSWAPD_RECLAIM) &
~(__GFP_MOVABLE | __GFP_COMP),
"wc huge", order);
ttm_page_pool_init_locked(&_manager->uc_pool_huge,
(GFP_TRANSHUGE_LIGHT | __GFP_NORETRY |
__GFP_KSWAPD_RECLAIM) &
~(__GFP_MOVABLE | __GFP_COMP)
, "uc huge", order);
_manager->options.max_size = max_pages;
_manager->options.small = SMALL_ALLOCATION;
_manager->options.alloc_size = NUM_PAGES_TO_ALLOC;
ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type,
&glob->kobj, "pool");
if (unlikely(ret != 0))
goto error;
ret = ttm_pool_mm_shrink_init(_manager);
if (unlikely(ret != 0))
goto error;
return 0;
error:
kobject_put(&_manager->kobj);
_manager = NULL;
return ret;
}
void ttm_page_alloc_fini(void)
{
int i;
pr_info("Finalizing pool allocator\n");
ttm_pool_mm_shrink_fini(_manager);
/* OK to use static buffer since global mutex is no longer used. */
for (i = 0; i < NUM_POOLS; ++i)
ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true);
kobject_put(&_manager->kobj);
_manager = NULL;
}
static void
ttm_pool_unpopulate_helper(struct ttm_tt *ttm, unsigned mem_count_update)
{
struct ttm_mem_global *mem_glob = &ttm_mem_glob;
unsigned i;
if (mem_count_update == 0)
goto put_pages;
for (i = 0; i < mem_count_update; ++i) {
if (!ttm->pages[i])
continue;
ttm_mem_global_free_page(mem_glob, ttm->pages[i], PAGE_SIZE);
}
put_pages:
ttm_put_pages(ttm->pages, ttm->num_pages, ttm->page_flags,
ttm->caching_state);
ttm->state = tt_unpopulated;
}
int ttm_pool_populate(struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
{
struct ttm_mem_global *mem_glob = &ttm_mem_glob;
unsigned i;
int ret;
if (ttm->state != tt_unpopulated)
return 0;
if (ttm_check_under_lowerlimit(mem_glob, ttm->num_pages, ctx))
return -ENOMEM;
ret = ttm_get_pages(ttm->pages, ttm->num_pages, ttm->page_flags,
ttm->caching_state);
if (unlikely(ret != 0)) {
ttm_pool_unpopulate_helper(ttm, 0);
return ret;
}
for (i = 0; i < ttm->num_pages; ++i) {
ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i],
PAGE_SIZE, ctx);
if (unlikely(ret != 0)) {
ttm_pool_unpopulate_helper(ttm, i);
return -ENOMEM;
}
}
if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
ret = ttm_tt_swapin(ttm);
if (unlikely(ret != 0)) {
ttm_pool_unpopulate(ttm);
return ret;
}
}
ttm->state = tt_unbound;
return 0;
}
EXPORT_SYMBOL(ttm_pool_populate);
void ttm_pool_unpopulate(struct ttm_tt *ttm)
{
ttm_pool_unpopulate_helper(ttm, ttm->num_pages);
}
EXPORT_SYMBOL(ttm_pool_unpopulate);
int ttm_populate_and_map_pages(struct device *dev, struct ttm_dma_tt *tt,
struct ttm_operation_ctx *ctx)
{
unsigned i, j;
int r;
r = ttm_pool_populate(&tt->ttm, ctx);
if (r)
return r;
for (i = 0; i < tt->ttm.num_pages; ++i) {
struct page *p = tt->ttm.pages[i];
size_t num_pages = 1;
for (j = i + 1; j < tt->ttm.num_pages; ++j) {
if (++p != tt->ttm.pages[j])
break;
++num_pages;
}
tt->dma_address[i] = dma_map_page(dev, tt->ttm.pages[i],
0, num_pages * PAGE_SIZE,
DMA_BIDIRECTIONAL);
if (dma_mapping_error(dev, tt->dma_address[i])) {
while (i--) {
dma_unmap_page(dev, tt->dma_address[i],
PAGE_SIZE, DMA_BIDIRECTIONAL);
tt->dma_address[i] = 0;
}
ttm_pool_unpopulate(&tt->ttm);
return -EFAULT;
}
for (j = 1; j < num_pages; ++j) {
tt->dma_address[i + 1] = tt->dma_address[i] + PAGE_SIZE;
++i;
}
}
return 0;
}
EXPORT_SYMBOL(ttm_populate_and_map_pages);
void ttm_unmap_and_unpopulate_pages(struct device *dev, struct ttm_dma_tt *tt)
{
unsigned i, j;
for (i = 0; i < tt->ttm.num_pages;) {
struct page *p = tt->ttm.pages[i];
size_t num_pages = 1;
if (!tt->dma_address[i] || !tt->ttm.pages[i]) {
++i;
continue;
}
for (j = i + 1; j < tt->ttm.num_pages; ++j) {
if (++p != tt->ttm.pages[j])
break;
++num_pages;
}
dma_unmap_page(dev, tt->dma_address[i], num_pages * PAGE_SIZE,
DMA_BIDIRECTIONAL);
i += num_pages;
}
ttm_pool_unpopulate(&tt->ttm);
}
EXPORT_SYMBOL(ttm_unmap_and_unpopulate_pages);
int ttm_page_alloc_debugfs(struct seq_file *m, void *data)
{
struct ttm_page_pool *p;
unsigned i;
char *h[] = {"pool", "refills", "pages freed", "size"};
if (!_manager) {
seq_printf(m, "No pool allocator running.\n");
return 0;
}
seq_printf(m, "%7s %12s %13s %8s\n",
h[0], h[1], h[2], h[3]);
for (i = 0; i < NUM_POOLS; ++i) {
p = &_manager->pools[i];
seq_printf(m, "%7s %12ld %13ld %8d\n",
p->name, p->nrefills,
p->nfrees, p->npages);
}
return 0;
}
EXPORT_SYMBOL(ttm_page_alloc_debugfs);