#include <linux/init.h>
#include <linux/hash.h>
#include <linux/highmem.h>
-#include <linux/blktrace_api.h>
#include <asm/tlbflush.h>
-static mempool_t *page_pool, *isa_page_pool;
-
-static void *mempool_alloc_pages_isa(gfp_t gfp_mask, void *data)
-{
- return mempool_alloc_pages(gfp_mask | GFP_DMA, data);
-}
-
/*
* Virtual_count is not a pure "count".
* 0 means that it is not mapped, and has not been mapped
*/
#ifdef CONFIG_HIGHMEM
+unsigned long totalhigh_pages __read_mostly;
+EXPORT_SYMBOL(totalhigh_pages);
+
+unsigned int nr_free_highpages (void)
+{
+ pg_data_t *pgdat;
+ unsigned int pages = 0;
+
+ for_each_online_pgdat(pgdat) {
+ pages += zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
+ NR_FREE_PAGES);
+ if (zone_movable_is_highmem())
+ pages += zone_page_state(
+ &pgdat->node_zones[ZONE_MOVABLE],
+ NR_FREE_PAGES);
+ }
+
+ return pages;
+}
+
static int pkmap_count[LAST_PKMAP];
static unsigned int last_pkmap_nr;
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(kmap_lock);
static DECLARE_WAIT_QUEUE_HEAD(pkmap_map_wait);
+/*
+ * Most architectures have no use for kmap_high_get(), so let's abstract
+ * the disabling of IRQ out of the locking in that case to save on a
+ * potential useless overhead.
+ */
+#ifdef ARCH_NEEDS_KMAP_HIGH_GET
+#define lock_kmap() spin_lock_irq(&kmap_lock)
+#define unlock_kmap() spin_unlock_irq(&kmap_lock)
+#define lock_kmap_any(flags) spin_lock_irqsave(&kmap_lock, flags)
+#define unlock_kmap_any(flags) spin_unlock_irqrestore(&kmap_lock, flags)
+#else
+#define lock_kmap() spin_lock(&kmap_lock)
+#define unlock_kmap() spin_unlock(&kmap_lock)
+#define lock_kmap_any(flags) \
+ do { spin_lock(&kmap_lock); (void)(flags); } while (0)
+#define unlock_kmap_any(flags) \
+ do { spin_unlock(&kmap_lock); (void)(flags); } while (0)
+#endif
+
static void flush_all_zero_pkmaps(void)
{
int i;
+ int need_flush = 0;
flush_cache_kmaps();
&pkmap_page_table[i]);
set_page_address(page, NULL);
+ need_flush = 1;
}
- flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
+ if (need_flush)
+ flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP));
+}
+
+/**
+ * kmap_flush_unused - flush all unused kmap mappings in order to remove stray mappings
+ */
+void kmap_flush_unused(void)
+{
+ lock_kmap();
+ flush_all_zero_pkmaps();
+ unlock_kmap();
}
static inline unsigned long map_new_virtual(struct page *page)
__set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(&pkmap_map_wait, &wait);
- spin_unlock(&kmap_lock);
+ unlock_kmap();
schedule();
remove_wait_queue(&pkmap_map_wait, &wait);
- spin_lock(&kmap_lock);
+ lock_kmap();
/* Somebody else might have mapped it while we slept */
if (page_address(page))
return vaddr;
}
-void fastcall *kmap_high(struct page *page)
+/**
+ * kmap_high - map a highmem page into memory
+ * @page: &struct page to map
+ *
+ * Returns the page's virtual memory address.
+ *
+ * We cannot call this from interrupts, as it may block.
+ */
+void *kmap_high(struct page *page)
{
unsigned long vaddr;
/*
* For highmem pages, we can't trust "virtual" until
* after we have the lock.
- *
- * We cannot call this from interrupts, as it may block
*/
- spin_lock(&kmap_lock);
+ lock_kmap();
vaddr = (unsigned long)page_address(page);
if (!vaddr)
vaddr = map_new_virtual(page);
pkmap_count[PKMAP_NR(vaddr)]++;
BUG_ON(pkmap_count[PKMAP_NR(vaddr)] < 2);
- spin_unlock(&kmap_lock);
+ unlock_kmap();
return (void*) vaddr;
}
EXPORT_SYMBOL(kmap_high);
-void fastcall kunmap_high(struct page *page)
+#ifdef ARCH_NEEDS_KMAP_HIGH_GET
+/**
+ * kmap_high_get - pin a highmem page into memory
+ * @page: &struct page to pin
+ *
+ * Returns the page's current virtual memory address, or NULL if no mapping
+ * exists. When and only when a non null address is returned then a
+ * matching call to kunmap_high() is necessary.
+ *
+ * This can be called from any context.
+ */
+void *kmap_high_get(struct page *page)
+{
+ unsigned long vaddr, flags;
+
+ lock_kmap_any(flags);
+ vaddr = (unsigned long)page_address(page);
+ if (vaddr) {
+ BUG_ON(pkmap_count[PKMAP_NR(vaddr)] < 1);
+ pkmap_count[PKMAP_NR(vaddr)]++;
+ }
+ unlock_kmap_any(flags);
+ return (void*) vaddr;
+}
+#endif
+
+/**
+ * kunmap_high - map a highmem page into memory
+ * @page: &struct page to unmap
+ *
+ * If ARCH_NEEDS_KMAP_HIGH_GET is not defined then this may be called
+ * only from user context.
+ */
+void kunmap_high(struct page *page)
{
unsigned long vaddr;
unsigned long nr;
+ unsigned long flags;
int need_wakeup;
- spin_lock(&kmap_lock);
+ lock_kmap_any(flags);
vaddr = (unsigned long)page_address(page);
BUG_ON(!vaddr);
nr = PKMAP_NR(vaddr);
*/
need_wakeup = waitqueue_active(&pkmap_map_wait);
}
- spin_unlock(&kmap_lock);
+ unlock_kmap_any(flags);
/* do wake-up, if needed, race-free outside of the spin lock */
if (need_wakeup)
}
EXPORT_SYMBOL(kunmap_high);
-
-#define POOL_SIZE 64
-
-static __init int init_emergency_pool(void)
-{
- struct sysinfo i;
- si_meminfo(&i);
- si_swapinfo(&i);
-
- if (!i.totalhigh)
- return 0;
-
- page_pool = mempool_create_page_pool(POOL_SIZE, 0);
- BUG_ON(!page_pool);
- printk("highmem bounce pool size: %d pages\n", POOL_SIZE);
-
- return 0;
-}
-
-__initcall(init_emergency_pool);
-
-/*
- * highmem version, map in to vec
- */
-static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom)
-{
- unsigned long flags;
- unsigned char *vto;
-
- local_irq_save(flags);
- vto = kmap_atomic(to->bv_page, KM_BOUNCE_READ);
- memcpy(vto + to->bv_offset, vfrom, to->bv_len);
- kunmap_atomic(vto, KM_BOUNCE_READ);
- local_irq_restore(flags);
-}
-
-#else /* CONFIG_HIGHMEM */
-
-#define bounce_copy_vec(to, vfrom) \
- memcpy(page_address((to)->bv_page) + (to)->bv_offset, vfrom, (to)->bv_len)
-
#endif
-#define ISA_POOL_SIZE 16
-
-/*
- * gets called "every" time someone init's a queue with BLK_BOUNCE_ISA
- * as the max address, so check if the pool has already been created.
- */
-int init_emergency_isa_pool(void)
-{
- if (isa_page_pool)
- return 0;
-
- isa_page_pool = mempool_create(ISA_POOL_SIZE, mempool_alloc_pages_isa,
- mempool_free_pages, (void *) 0);
- BUG_ON(!isa_page_pool);
-
- printk("isa bounce pool size: %d pages\n", ISA_POOL_SIZE);
- return 0;
-}
-
-/*
- * Simple bounce buffer support for highmem pages. Depending on the
- * queue gfp mask set, *to may or may not be a highmem page. kmap it
- * always, it will do the Right Thing
- */
-static void copy_to_high_bio_irq(struct bio *to, struct bio *from)
-{
- unsigned char *vfrom;
- struct bio_vec *tovec, *fromvec;
- int i;
-
- __bio_for_each_segment(tovec, to, i, 0) {
- fromvec = from->bi_io_vec + i;
-
- /*
- * not bounced
- */
- if (tovec->bv_page == fromvec->bv_page)
- continue;
-
- /*
- * fromvec->bv_offset and fromvec->bv_len might have been
- * modified by the block layer, so use the original copy,
- * bounce_copy_vec already uses tovec->bv_len
- */
- vfrom = page_address(fromvec->bv_page) + tovec->bv_offset;
-
- flush_dcache_page(tovec->bv_page);
- bounce_copy_vec(tovec, vfrom);
- }
-}
-
-static void bounce_end_io(struct bio *bio, mempool_t *pool, int err)
-{
- struct bio *bio_orig = bio->bi_private;
- struct bio_vec *bvec, *org_vec;
- int i;
-
- if (test_bit(BIO_EOPNOTSUPP, &bio->bi_flags))
- set_bit(BIO_EOPNOTSUPP, &bio_orig->bi_flags);
-
- /*
- * free up bounce indirect pages used
- */
- __bio_for_each_segment(bvec, bio, i, 0) {
- org_vec = bio_orig->bi_io_vec + i;
- if (bvec->bv_page == org_vec->bv_page)
- continue;
-
- dec_zone_page_state(bvec->bv_page, NR_BOUNCE);
- mempool_free(bvec->bv_page, pool);
- }
-
- bio_endio(bio_orig, bio_orig->bi_size, err);
- bio_put(bio);
-}
-
-static int bounce_end_io_write(struct bio *bio, unsigned int bytes_done, int err)
-{
- if (bio->bi_size)
- return 1;
-
- bounce_end_io(bio, page_pool, err);
- return 0;
-}
-
-static int bounce_end_io_write_isa(struct bio *bio, unsigned int bytes_done, int err)
-{
- if (bio->bi_size)
- return 1;
-
- bounce_end_io(bio, isa_page_pool, err);
- return 0;
-}
-
-static void __bounce_end_io_read(struct bio *bio, mempool_t *pool, int err)
-{
- struct bio *bio_orig = bio->bi_private;
-
- if (test_bit(BIO_UPTODATE, &bio->bi_flags))
- copy_to_high_bio_irq(bio_orig, bio);
-
- bounce_end_io(bio, pool, err);
-}
-
-static int bounce_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
-{
- if (bio->bi_size)
- return 1;
-
- __bounce_end_io_read(bio, page_pool, err);
- return 0;
-}
-
-static int bounce_end_io_read_isa(struct bio *bio, unsigned int bytes_done, int err)
-{
- if (bio->bi_size)
- return 1;
-
- __bounce_end_io_read(bio, isa_page_pool, err);
- return 0;
-}
-
-static void __blk_queue_bounce(request_queue_t *q, struct bio **bio_orig,
- mempool_t *pool)
-{
- struct page *page;
- struct bio *bio = NULL;
- int i, rw = bio_data_dir(*bio_orig);
- struct bio_vec *to, *from;
-
- bio_for_each_segment(from, *bio_orig, i) {
- page = from->bv_page;
-
- /*
- * is destination page below bounce pfn?
- */
- if (page_to_pfn(page) < q->bounce_pfn)
- continue;
-
- /*
- * irk, bounce it
- */
- if (!bio)
- bio = bio_alloc(GFP_NOIO, (*bio_orig)->bi_vcnt);
-
- to = bio->bi_io_vec + i;
-
- to->bv_page = mempool_alloc(pool, q->bounce_gfp);
- to->bv_len = from->bv_len;
- to->bv_offset = from->bv_offset;
- inc_zone_page_state(to->bv_page, NR_BOUNCE);
-
- if (rw == WRITE) {
- char *vto, *vfrom;
-
- flush_dcache_page(from->bv_page);
- vto = page_address(to->bv_page) + to->bv_offset;
- vfrom = kmap(from->bv_page) + from->bv_offset;
- memcpy(vto, vfrom, to->bv_len);
- kunmap(from->bv_page);
- }
- }
-
- /*
- * no pages bounced
- */
- if (!bio)
- return;
-
- /*
- * at least one page was bounced, fill in possible non-highmem
- * pages
- */
- __bio_for_each_segment(from, *bio_orig, i, 0) {
- to = bio_iovec_idx(bio, i);
- if (!to->bv_page) {
- to->bv_page = from->bv_page;
- to->bv_len = from->bv_len;
- to->bv_offset = from->bv_offset;
- }
- }
-
- bio->bi_bdev = (*bio_orig)->bi_bdev;
- bio->bi_flags |= (1 << BIO_BOUNCED);
- bio->bi_sector = (*bio_orig)->bi_sector;
- bio->bi_rw = (*bio_orig)->bi_rw;
-
- bio->bi_vcnt = (*bio_orig)->bi_vcnt;
- bio->bi_idx = (*bio_orig)->bi_idx;
- bio->bi_size = (*bio_orig)->bi_size;
-
- if (pool == page_pool) {
- bio->bi_end_io = bounce_end_io_write;
- if (rw == READ)
- bio->bi_end_io = bounce_end_io_read;
- } else {
- bio->bi_end_io = bounce_end_io_write_isa;
- if (rw == READ)
- bio->bi_end_io = bounce_end_io_read_isa;
- }
-
- bio->bi_private = *bio_orig;
- *bio_orig = bio;
-}
-
-void blk_queue_bounce(request_queue_t *q, struct bio **bio_orig)
-{
- mempool_t *pool;
-
- /*
- * for non-isa bounce case, just check if the bounce pfn is equal
- * to or bigger than the highest pfn in the system -- in that case,
- * don't waste time iterating over bio segments
- */
- if (!(q->bounce_gfp & GFP_DMA)) {
- if (q->bounce_pfn >= blk_max_pfn)
- return;
- pool = page_pool;
- } else {
- BUG_ON(!isa_page_pool);
- pool = isa_page_pool;
- }
-
- blk_add_trace_bio(q, *bio_orig, BLK_TA_BOUNCE);
-
- /*
- * slow path
- */
- __blk_queue_bounce(q, bio_orig, pool);
-}
-
-EXPORT_SYMBOL(blk_queue_bounce);
-
#if defined(HASHED_PAGE_VIRTUAL)
#define PA_HASH_ORDER 7
return &page_address_htable[hash_ptr(page, PA_HASH_ORDER)];
}
+/**
+ * page_address - get the mapped virtual address of a page
+ * @page: &struct page to get the virtual address of
+ *
+ * Returns the page's virtual address.
+ */
void *page_address(struct page *page)
{
unsigned long flags;
EXPORT_SYMBOL(page_address);
+/**
+ * set_page_address - set a page's virtual address
+ * @page: &struct page to set
+ * @virtual: virtual address to use
+ */
void set_page_address(struct page *page, void *virtual)
{
unsigned long flags;
}
#endif /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */
+
+#if defined(CONFIG_DEBUG_HIGHMEM) && defined(CONFIG_TRACE_IRQFLAGS_SUPPORT)
+
+void debug_kmap_atomic(enum km_type type)
+{
+ static int warn_count = 10;
+
+ if (unlikely(warn_count < 0))
+ return;
+
+ if (unlikely(in_interrupt())) {
+ if (in_nmi()) {
+ if (type != KM_NMI && type != KM_NMI_PTE) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ } else if (in_irq()) {
+ if (type != KM_IRQ0 && type != KM_IRQ1 &&
+ type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ &&
+ type != KM_BOUNCE_READ && type != KM_IRQ_PTE) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ } else if (!irqs_disabled()) { /* softirq */
+ if (type != KM_IRQ0 && type != KM_IRQ1 &&
+ type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
+ type != KM_SKB_SUNRPC_DATA &&
+ type != KM_SKB_DATA_SOFTIRQ &&
+ type != KM_BOUNCE_READ) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ }
+ }
+
+ if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
+ type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ ||
+ type == KM_IRQ_PTE || type == KM_NMI ||
+ type == KM_NMI_PTE ) {
+ if (!irqs_disabled()) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ } else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
+ if (irq_count() == 0 && !irqs_disabled()) {
+ WARN_ON(1);
+ warn_count--;
+ }
+ }
+}
+
+#endif
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff