/*
- * PPC64 (POWER4) Huge TLB Page Support for Kernel.
+ * PPC Huge TLB Page Support for Kernel.
*
* Copyright (C) 2003 David Gibson, IBM Corporation.
+ * Copyright (C) 2011 Becky Bruce, Freescale Semiconductor
*
* Based on the IA-32 version:
* Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/hugetlb.h>
+#include <linux/of_fdt.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
+#include <asm/setup.h>
#define PAGE_SHIFT_64K 16
#define PAGE_SHIFT_16M 24
#define PAGE_SHIFT_16G 34
-#define MAX_NUMBER_GPAGES 1024
+unsigned int HPAGE_SHIFT;
-/* Tracks the 16G pages after the device tree is scanned and before the
- * huge_boot_pages list is ready. */
-static unsigned long gpage_freearray[MAX_NUMBER_GPAGES];
+/*
+ * Tracks gpages after the device tree is scanned and before the
+ * huge_boot_pages list is ready. On 64-bit implementations, this is
+ * just used to track 16G pages and so is a single array. 32-bit
+ * implementations may have more than one gpage size due to limitations
+ * of the memory allocators, so we need multiple arrays
+ */
+#ifdef CONFIG_PPC64
+#define MAX_NUMBER_GPAGES 1024
+static u64 gpage_freearray[MAX_NUMBER_GPAGES];
static unsigned nr_gpages;
-
-/* Flag to mark huge PD pointers. This means pmd_bad() and pud_bad()
- * will choke on pointers to hugepte tables, which is handy for
- * catching screwups early. */
+#else
+#define MAX_NUMBER_GPAGES 128
+struct psize_gpages {
+ u64 gpage_list[MAX_NUMBER_GPAGES];
+ unsigned int nr_gpages;
+};
+static struct psize_gpages gpage_freearray[MMU_PAGE_COUNT];
+#endif
static inline int shift_to_mmu_psize(unsigned int shift)
{
#define hugepd_none(hpd) ((hpd).pd == 0)
-static inline pte_t *hugepd_page(hugepd_t hpd)
-{
- BUG_ON(!hugepd_ok(hpd));
- return (pte_t *)((hpd.pd & ~HUGEPD_SHIFT_MASK) | 0xc000000000000000);
-}
-
-static inline unsigned int hugepd_shift(hugepd_t hpd)
-{
- return hpd.pd & HUGEPD_SHIFT_MASK;
-}
-
-static inline pte_t *hugepte_offset(hugepd_t *hpdp, unsigned long addr, unsigned pdshift)
-{
- unsigned long idx = (addr & ((1UL << pdshift) - 1)) >> hugepd_shift(*hpdp);
- pte_t *dir = hugepd_page(*hpdp);
-
- return dir + idx;
-}
-
pte_t *find_linux_pte_or_hugepte(pgd_t *pgdir, unsigned long ea, unsigned *shift)
{
pgd_t *pg;
if (is_hugepd(pm))
hpdp = (hugepd_t *)pm;
else if (!pmd_none(*pm)) {
- return pte_offset_map(pm, ea);
+ return pte_offset_kernel(pm, ea);
}
}
}
static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
unsigned long address, unsigned pdshift, unsigned pshift)
{
- pte_t *new = kmem_cache_zalloc(PGT_CACHE(pdshift - pshift),
- GFP_KERNEL|__GFP_REPEAT);
+ struct kmem_cache *cachep;
+ pte_t *new;
+
+#ifdef CONFIG_PPC64
+ cachep = PGT_CACHE(pdshift - pshift);
+#else
+ int i;
+ int num_hugepd = 1 << (pshift - pdshift);
+ cachep = hugepte_cache;
+#endif
+
+ new = kmem_cache_zalloc(cachep, GFP_KERNEL|__GFP_REPEAT);
BUG_ON(pshift > HUGEPD_SHIFT_MASK);
BUG_ON((unsigned long)new & HUGEPD_SHIFT_MASK);
return -ENOMEM;
spin_lock(&mm->page_table_lock);
+#ifdef CONFIG_PPC64
if (!hugepd_none(*hpdp))
- kmem_cache_free(PGT_CACHE(pdshift - pshift), new);
+ kmem_cache_free(cachep, new);
else
- hpdp->pd = ((unsigned long)new & ~0x8000000000000000) | pshift;
+ hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift;
+#else
+ /*
+ * We have multiple higher-level entries that point to the same
+ * actual pte location. Fill in each as we go and backtrack on error.
+ * We need all of these so the DTLB pgtable walk code can find the
+ * right higher-level entry without knowing if it's a hugepage or not.
+ */
+ for (i = 0; i < num_hugepd; i++, hpdp++) {
+ if (unlikely(!hugepd_none(*hpdp)))
+ break;
+ else
+ hpdp->pd = ((unsigned long)new & ~PD_HUGE) | pshift;
+ }
+ /* If we bailed from the for loop early, an error occurred, clean up */
+ if (i < num_hugepd) {
+ for (i = i - 1 ; i >= 0; i--, hpdp--)
+ hpdp->pd = 0;
+ kmem_cache_free(cachep, new);
+ }
+#endif
spin_unlock(&mm->page_table_lock);
return 0;
}
return hugepte_offset(hpdp, addr, pdshift);
}
+#ifdef CONFIG_PPC32
/* Build list of addresses of gigantic pages. This function is used in early
* boot before the buddy or bootmem allocator is setup.
*/
-void add_gpage(unsigned long addr, unsigned long page_size,
- unsigned long number_of_pages)
+void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
+{
+ unsigned int idx = shift_to_mmu_psize(__ffs(page_size));
+ int i;
+
+ if (addr == 0)
+ return;
+
+ gpage_freearray[idx].nr_gpages = number_of_pages;
+
+ for (i = 0; i < number_of_pages; i++) {
+ gpage_freearray[idx].gpage_list[i] = addr;
+ addr += page_size;
+ }
+}
+
+/*
+ * Moves the gigantic page addresses from the temporary list to the
+ * huge_boot_pages list.
+ */
+int alloc_bootmem_huge_page(struct hstate *hstate)
+{
+ struct huge_bootmem_page *m;
+ int idx = shift_to_mmu_psize(hstate->order + PAGE_SHIFT);
+ int nr_gpages = gpage_freearray[idx].nr_gpages;
+
+ if (nr_gpages == 0)
+ return 0;
+
+#ifdef CONFIG_HIGHMEM
+ /*
+ * If gpages can be in highmem we can't use the trick of storing the
+ * data structure in the page; allocate space for this
+ */
+ m = alloc_bootmem(sizeof(struct huge_bootmem_page));
+ m->phys = gpage_freearray[idx].gpage_list[--nr_gpages];
+#else
+ m = phys_to_virt(gpage_freearray[idx].gpage_list[--nr_gpages]);
+#endif
+
+ list_add(&m->list, &huge_boot_pages);
+ gpage_freearray[idx].nr_gpages = nr_gpages;
+ gpage_freearray[idx].gpage_list[nr_gpages] = 0;
+ m->hstate = hstate;
+
+ return 1;
+}
+/*
+ * Scan the command line hugepagesz= options for gigantic pages; store those in
+ * a list that we use to allocate the memory once all options are parsed.
+ */
+
+unsigned long gpage_npages[MMU_PAGE_COUNT];
+
+static int __init do_gpage_early_setup(char *param, char *val)
+{
+ static phys_addr_t size;
+ unsigned long npages;
+
+ /*
+ * The hugepagesz and hugepages cmdline options are interleaved. We
+ * use the size variable to keep track of whether or not this was done
+ * properly and skip over instances where it is incorrect. Other
+ * command-line parsing code will issue warnings, so we don't need to.
+ *
+ */
+ if ((strcmp(param, "default_hugepagesz") == 0) ||
+ (strcmp(param, "hugepagesz") == 0)) {
+ size = memparse(val, NULL);
+ } else if (strcmp(param, "hugepages") == 0) {
+ if (size != 0) {
+ if (sscanf(val, "%lu", &npages) <= 0)
+ npages = 0;
+ gpage_npages[shift_to_mmu_psize(__ffs(size))] = npages;
+ size = 0;
+ }
+ }
+ return 0;
+}
+
+
+/*
+ * This function allocates physical space for pages that are larger than the
+ * buddy allocator can handle. We want to allocate these in highmem because
+ * the amount of lowmem is limited. This means that this function MUST be
+ * called before lowmem_end_addr is set up in MMU_init() in order for the lmb
+ * allocate to grab highmem.
+ */
+void __init reserve_hugetlb_gpages(void)
+{
+ static __initdata char cmdline[COMMAND_LINE_SIZE];
+ phys_addr_t size, base;
+ int i;
+
+ strlcpy(cmdline, boot_command_line, COMMAND_LINE_SIZE);
+ parse_args("hugetlb gpages", cmdline, NULL, 0, &do_gpage_early_setup);
+
+ /*
+ * Walk gpage list in reverse, allocating larger page sizes first.
+ * Skip over unsupported sizes, or sizes that have 0 gpages allocated.
+ * When we reach the point in the list where pages are no longer
+ * considered gpages, we're done.
+ */
+ for (i = MMU_PAGE_COUNT-1; i >= 0; i--) {
+ if (mmu_psize_defs[i].shift == 0 || gpage_npages[i] == 0)
+ continue;
+ else if (mmu_psize_to_shift(i) < (MAX_ORDER + PAGE_SHIFT))
+ break;
+
+ size = (phys_addr_t)(1ULL << mmu_psize_to_shift(i));
+ base = memblock_alloc_base(size * gpage_npages[i], size,
+ MEMBLOCK_ALLOC_ANYWHERE);
+ add_gpage(base, size, gpage_npages[i]);
+ }
+}
+
+#else /* PPC64 */
+
+/* Build list of addresses of gigantic pages. This function is used in early
+ * boot before the buddy or bootmem allocator is setup.
+ */
+void add_gpage(u64 addr, u64 page_size, unsigned long number_of_pages)
{
if (!addr)
return;
m->hstate = hstate;
return 1;
}
+#endif
int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
{
return 0;
}
+#ifdef CONFIG_PPC32
+#define HUGEPD_FREELIST_SIZE \
+ ((PAGE_SIZE - sizeof(struct hugepd_freelist)) / sizeof(pte_t))
+
+struct hugepd_freelist {
+ struct rcu_head rcu;
+ unsigned int index;
+ void *ptes[0];
+};
+
+static DEFINE_PER_CPU(struct hugepd_freelist *, hugepd_freelist_cur);
+
+static void hugepd_free_rcu_callback(struct rcu_head *head)
+{
+ struct hugepd_freelist *batch =
+ container_of(head, struct hugepd_freelist, rcu);
+ unsigned int i;
+
+ for (i = 0; i < batch->index; i++)
+ kmem_cache_free(hugepte_cache, batch->ptes[i]);
+
+ free_page((unsigned long)batch);
+}
+
+static void hugepd_free(struct mmu_gather *tlb, void *hugepte)
+{
+ struct hugepd_freelist **batchp;
+
+ batchp = &__get_cpu_var(hugepd_freelist_cur);
+
+ if (atomic_read(&tlb->mm->mm_users) < 2 ||
+ cpumask_equal(mm_cpumask(tlb->mm),
+ cpumask_of(smp_processor_id()))) {
+ kmem_cache_free(hugepte_cache, hugepte);
+ return;
+ }
+
+ if (*batchp == NULL) {
+ *batchp = (struct hugepd_freelist *)__get_free_page(GFP_ATOMIC);
+ (*batchp)->index = 0;
+ }
+
+ (*batchp)->ptes[(*batchp)->index++] = hugepte;
+ if ((*batchp)->index == HUGEPD_FREELIST_SIZE) {
+ call_rcu_sched(&(*batchp)->rcu, hugepd_free_rcu_callback);
+ *batchp = NULL;
+ }
+}
+#endif
+
static void free_hugepd_range(struct mmu_gather *tlb, hugepd_t *hpdp, int pdshift,
unsigned long start, unsigned long end,
unsigned long floor, unsigned long ceiling)
{
pte_t *hugepte = hugepd_page(*hpdp);
- unsigned shift = hugepd_shift(*hpdp);
+ int i;
+
unsigned long pdmask = ~((1UL << pdshift) - 1);
+ unsigned int num_hugepd = 1;
+
+#ifdef CONFIG_PPC64
+ unsigned int shift = hugepd_shift(*hpdp);
+#else
+ /* Note: On 32-bit the hpdp may be the first of several */
+ num_hugepd = (1 << (hugepd_shift(*hpdp) - pdshift));
+#endif
start &= pdmask;
if (start < floor)
if (end - 1 > ceiling - 1)
return;
- hpdp->pd = 0;
+ for (i = 0; i < num_hugepd; i++, hpdp++)
+ hpdp->pd = 0;
+
tlb->need_flush = 1;
+#ifdef CONFIG_PPC64
pgtable_free_tlb(tlb, hugepte, pdshift - shift);
+#else
+ hugepd_free(tlb, hugepte);
+#endif
}
static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
* too.
*/
- pgd = pgd_offset(tlb->mm, addr);
do {
next = pgd_addr_end(addr, end);
+ pgd = pgd_offset(tlb->mm, addr);
if (!is_hugepd(pgd)) {
if (pgd_none_or_clear_bad(pgd))
continue;
hugetlb_free_pud_range(tlb, pgd, addr, next, floor, ceiling);
} else {
+#ifdef CONFIG_PPC32
+ /*
+ * Increment next by the size of the huge mapping since
+ * on 32-bit there may be more than one entry at the pgd
+ * level for a single hugepage, but all of them point to
+ * the same kmem cache that holds the hugepte.
+ */
+ next = addr + (1 << hugepd_shift(*(hugepd_t *)pgd));
+#endif
free_hugepd_range(tlb, (hugepd_t *)pgd, PGDIR_SHIFT,
addr, next, floor, ceiling);
}
- } while (pgd++, addr = next, addr != end);
+ } while (addr = next, addr != end);
}
struct page *
unsigned long len, unsigned long pgoff,
unsigned long flags)
{
+#ifdef CONFIG_PPC_MM_SLICES
struct hstate *hstate = hstate_file(file);
int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1, 0);
+#else
+ return get_unmapped_area(file, addr, len, pgoff, flags);
+#endif
}
unsigned long vma_mmu_pagesize(struct vm_area_struct *vma)
{
+#ifdef CONFIG_PPC_MM_SLICES
unsigned int psize = get_slice_psize(vma->vm_mm, vma->vm_start);
return 1UL << mmu_psize_to_shift(psize);
+#else
+ if (!is_vm_hugetlb_page(vma))
+ return PAGE_SIZE;
+
+ return huge_page_size(hstate_vma(vma));
+#endif
+}
+
+static inline bool is_power_of_4(unsigned long x)
+{
+ if (is_power_of_2(x))
+ return (__ilog2(x) % 2) ? false : true;
+ return false;
}
static int __init add_huge_page_size(unsigned long long size)
/* Check that it is a page size supported by the hardware and
* that it fits within pagetable and slice limits. */
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ if ((size < PAGE_SIZE) || !is_power_of_4(size))
+ return -EINVAL;
+#else
if (!is_power_of_2(size)
|| (shift > SLICE_HIGH_SHIFT) || (shift <= PAGE_SHIFT))
return -EINVAL;
+#endif
if ((mmu_psize = shift_to_mmu_psize(shift)) < 0)
return -EINVAL;
}
__setup("hugepagesz=", hugepage_setup_sz);
+#ifdef CONFIG_FSL_BOOKE
+struct kmem_cache *hugepte_cache;
+static int __init hugetlbpage_init(void)
+{
+ int psize;
+
+ for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
+ unsigned shift;
+
+ if (!mmu_psize_defs[psize].shift)
+ continue;
+
+ shift = mmu_psize_to_shift(psize);
+
+ /* Don't treat normal page sizes as huge... */
+ if (shift != PAGE_SHIFT)
+ if (add_huge_page_size(1ULL << shift) < 0)
+ continue;
+ }
+
+ /*
+ * Create a kmem cache for hugeptes. The bottom bits in the pte have
+ * size information encoded in them, so align them to allow this
+ */
+ hugepte_cache = kmem_cache_create("hugepte-cache", sizeof(pte_t),
+ HUGEPD_SHIFT_MASK + 1, 0, NULL);
+ if (hugepte_cache == NULL)
+ panic("%s: Unable to create kmem cache for hugeptes\n",
+ __func__);
+
+ /* Default hpage size = 4M */
+ if (mmu_psize_defs[MMU_PAGE_4M].shift)
+ HPAGE_SHIFT = mmu_psize_defs[MMU_PAGE_4M].shift;
+ else
+ panic("%s: Unable to set default huge page size\n", __func__);
+
+
+ return 0;
+}
+#else
static int __init hugetlbpage_init(void)
{
int psize;
return 0;
}
-
+#endif
module_init(hugetlbpage_init);
void flush_dcache_icache_hugepage(struct page *page)
{
int i;
+ void *start;
BUG_ON(!PageCompound(page));
- for (i = 0; i < (1UL << compound_order(page)); i++)
- __flush_dcache_icache(page_address(page+i));
+ for (i = 0; i < (1UL << compound_order(page)); i++) {
+ if (!PageHighMem(page)) {
+ __flush_dcache_icache(page_address(page+i));
+ } else {
+ start = kmap_atomic(page+i, KM_PPC_SYNC_ICACHE);
+ __flush_dcache_icache(start);
+ kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
+ }
+ }
}
git.openpandora.org / pandora-kernel.git / blobdiff