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authorJeff Garzik <jgarzik@pobox.com>2005-09-02 00:02:01 +0200
committerJeff Garzik <jgarzik@pobox.com>2005-09-02 00:02:01 +0200
commite3ee3b78f83688a0ae4315e8be71b2eac559904a (patch)
treedeb03bcdd020262af450ed23382d7c921263f5cf /arch/ppc64/mm/hugetlbpage.c
parent[PATCH] ieee80211: Fix debug comments ipw->ieee80211 (diff)
parentMerge refs/heads/upstream from master.kernel.org:/pub/scm/linux/kernel/git/jg... (diff)
downloadlinux-e3ee3b78f83688a0ae4315e8be71b2eac559904a.tar.xz
linux-e3ee3b78f83688a0ae4315e8be71b2eac559904a.zip
/spare/repo/netdev-2.6 branch 'master'
Diffstat (limited to 'arch/ppc64/mm/hugetlbpage.c')
-rw-r--r--arch/ppc64/mm/hugetlbpage.c388
1 files changed, 212 insertions, 176 deletions
diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c
index f9524602818d..e7833c80eb68 100644
--- a/arch/ppc64/mm/hugetlbpage.c
+++ b/arch/ppc64/mm/hugetlbpage.c
@@ -27,124 +27,94 @@
#include <linux/sysctl.h>
-#define HUGEPGDIR_SHIFT (HPAGE_SHIFT + PAGE_SHIFT - 3)
-#define HUGEPGDIR_SIZE (1UL << HUGEPGDIR_SHIFT)
-#define HUGEPGDIR_MASK (~(HUGEPGDIR_SIZE-1))
+#define NUM_LOW_AREAS (0x100000000UL >> SID_SHIFT)
+#define NUM_HIGH_AREAS (PGTABLE_RANGE >> HTLB_AREA_SHIFT)
-#define HUGEPTE_INDEX_SIZE 9
-#define HUGEPGD_INDEX_SIZE 10
-
-#define PTRS_PER_HUGEPTE (1 << HUGEPTE_INDEX_SIZE)
-#define PTRS_PER_HUGEPGD (1 << HUGEPGD_INDEX_SIZE)
-
-static inline int hugepgd_index(unsigned long addr)
-{
- return (addr & ~REGION_MASK) >> HUGEPGDIR_SHIFT;
-}
-
-static pud_t *hugepgd_offset(struct mm_struct *mm, unsigned long addr)
+/* Modelled after find_linux_pte() */
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
- int index;
+ pgd_t *pg;
+ pud_t *pu;
+ pmd_t *pm;
+ pte_t *pt;
- if (! mm->context.huge_pgdir)
- return NULL;
+ BUG_ON(! in_hugepage_area(mm->context, addr));
+ addr &= HPAGE_MASK;
+
+ pg = pgd_offset(mm, addr);
+ if (!pgd_none(*pg)) {
+ pu = pud_offset(pg, addr);
+ if (!pud_none(*pu)) {
+ pm = pmd_offset(pu, addr);
+ pt = (pte_t *)pm;
+ BUG_ON(!pmd_none(*pm)
+ && !(pte_present(*pt) && pte_huge(*pt)));
+ return pt;
+ }
+ }
- index = hugepgd_index(addr);
- BUG_ON(index >= PTRS_PER_HUGEPGD);
- return (pud_t *)(mm->context.huge_pgdir + index);
+ return NULL;
}
-static inline pte_t *hugepte_offset(pud_t *dir, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
{
- int index;
-
- if (pud_none(*dir))
- return NULL;
+ pgd_t *pg;
+ pud_t *pu;
+ pmd_t *pm;
+ pte_t *pt;
- index = (addr >> HPAGE_SHIFT) % PTRS_PER_HUGEPTE;
- return (pte_t *)pud_page(*dir) + index;
-}
-
-static pud_t *hugepgd_alloc(struct mm_struct *mm, unsigned long addr)
-{
BUG_ON(! in_hugepage_area(mm->context, addr));
- if (! mm->context.huge_pgdir) {
- pgd_t *new;
- spin_unlock(&mm->page_table_lock);
- /* Don't use pgd_alloc(), because we want __GFP_REPEAT */
- new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT);
- BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE));
- spin_lock(&mm->page_table_lock);
+ addr &= HPAGE_MASK;
- /*
- * Because we dropped the lock, we should re-check the
- * entry, as somebody else could have populated it..
- */
- if (mm->context.huge_pgdir)
- pgd_free(new);
- else
- mm->context.huge_pgdir = new;
- }
- return hugepgd_offset(mm, addr);
-}
+ pg = pgd_offset(mm, addr);
+ pu = pud_alloc(mm, pg, addr);
-static pte_t *hugepte_alloc(struct mm_struct *mm, pud_t *dir, unsigned long addr)
-{
- if (! pud_present(*dir)) {
- pte_t *new;
-
- spin_unlock(&mm->page_table_lock);
- new = kmem_cache_alloc(zero_cache, GFP_KERNEL | __GFP_REPEAT);
- BUG_ON(memcmp(new, empty_zero_page, PAGE_SIZE));
- spin_lock(&mm->page_table_lock);
- /*
- * Because we dropped the lock, we should re-check the
- * entry, as somebody else could have populated it..
- */
- if (pud_present(*dir)) {
- if (new)
- kmem_cache_free(zero_cache, new);
- } else {
- struct page *ptepage;
-
- if (! new)
- return NULL;
- ptepage = virt_to_page(new);
- ptepage->mapping = (void *) mm;
- ptepage->index = addr & HUGEPGDIR_MASK;
- pud_populate(mm, dir, new);
+ if (pu) {
+ pm = pmd_alloc(mm, pu, addr);
+ if (pm) {
+ pt = (pte_t *)pm;
+ BUG_ON(!pmd_none(*pm)
+ && !(pte_present(*pt) && pte_huge(*pt)));
+ return pt;
}
}
- return hugepte_offset(dir, addr);
+ return NULL;
}
-pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
-{
- pud_t *pud;
+#define HUGEPTE_BATCH_SIZE (HPAGE_SIZE / PMD_SIZE)
- BUG_ON(! in_hugepage_area(mm->context, addr));
+void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ int i;
- pud = hugepgd_offset(mm, addr);
- if (! pud)
- return NULL;
+ if (pte_present(*ptep)) {
+ pte_clear(mm, addr, ptep);
+ flush_tlb_pending();
+ }
- return hugepte_offset(pud, addr);
+ for (i = 0; i < HUGEPTE_BATCH_SIZE; i++) {
+ *ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
+ ptep++;
+ }
}
-pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep)
{
- pud_t *pud;
+ unsigned long old = pte_update(ptep, ~0UL);
+ int i;
- BUG_ON(! in_hugepage_area(mm->context, addr));
+ if (old & _PAGE_HASHPTE)
+ hpte_update(mm, addr, old, 0);
- pud = hugepgd_alloc(mm, addr);
- if (! pud)
- return NULL;
+ for (i = 1; i < HUGEPTE_BATCH_SIZE; i++)
+ ptep[i] = __pte(0);
- return hugepte_alloc(mm, pud, addr);
+ return __pte(old);
}
/*
@@ -162,15 +132,17 @@ int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
return 0;
}
-static void flush_segments(void *parm)
+static void flush_low_segments(void *parm)
{
- u16 segs = (unsigned long) parm;
+ u16 areas = (unsigned long) parm;
unsigned long i;
asm volatile("isync" : : : "memory");
- for (i = 0; i < 16; i++) {
- if (! (segs & (1U << i)))
+ BUILD_BUG_ON((sizeof(areas)*8) != NUM_LOW_AREAS);
+
+ for (i = 0; i < NUM_LOW_AREAS; i++) {
+ if (! (areas & (1U << i)))
continue;
asm volatile("slbie %0" : : "r" (i << SID_SHIFT));
}
@@ -178,13 +150,33 @@ static void flush_segments(void *parm)
asm volatile("isync" : : : "memory");
}
-static int prepare_low_seg_for_htlb(struct mm_struct *mm, unsigned long seg)
+static void flush_high_segments(void *parm)
{
- unsigned long start = seg << SID_SHIFT;
- unsigned long end = (seg+1) << SID_SHIFT;
+ u16 areas = (unsigned long) parm;
+ unsigned long i, j;
+
+ asm volatile("isync" : : : "memory");
+
+ BUILD_BUG_ON((sizeof(areas)*8) != NUM_HIGH_AREAS);
+
+ for (i = 0; i < NUM_HIGH_AREAS; i++) {
+ if (! (areas & (1U << i)))
+ continue;
+ for (j = 0; j < (1UL << (HTLB_AREA_SHIFT-SID_SHIFT)); j++)
+ asm volatile("slbie %0"
+ :: "r" ((i << HTLB_AREA_SHIFT) + (j << SID_SHIFT)));
+ }
+
+ asm volatile("isync" : : : "memory");
+}
+
+static int prepare_low_area_for_htlb(struct mm_struct *mm, unsigned long area)
+{
+ unsigned long start = area << SID_SHIFT;
+ unsigned long end = (area+1) << SID_SHIFT;
struct vm_area_struct *vma;
- BUG_ON(seg >= 16);
+ BUG_ON(area >= NUM_LOW_AREAS);
/* Check no VMAs are in the region */
vma = find_vma(mm, start);
@@ -194,20 +186,39 @@ static int prepare_low_seg_for_htlb(struct mm_struct *mm, unsigned long seg)
return 0;
}
-static int open_low_hpage_segs(struct mm_struct *mm, u16 newsegs)
+static int prepare_high_area_for_htlb(struct mm_struct *mm, unsigned long area)
+{
+ unsigned long start = area << HTLB_AREA_SHIFT;
+ unsigned long end = (area+1) << HTLB_AREA_SHIFT;
+ struct vm_area_struct *vma;
+
+ BUG_ON(area >= NUM_HIGH_AREAS);
+
+ /* Check no VMAs are in the region */
+ vma = find_vma(mm, start);
+ if (vma && (vma->vm_start < end))
+ return -EBUSY;
+
+ return 0;
+}
+
+static int open_low_hpage_areas(struct mm_struct *mm, u16 newareas)
{
unsigned long i;
- newsegs &= ~(mm->context.htlb_segs);
- if (! newsegs)
+ BUILD_BUG_ON((sizeof(newareas)*8) != NUM_LOW_AREAS);
+ BUILD_BUG_ON((sizeof(mm->context.low_htlb_areas)*8) != NUM_LOW_AREAS);
+
+ newareas &= ~(mm->context.low_htlb_areas);
+ if (! newareas)
return 0; /* The segments we want are already open */
- for (i = 0; i < 16; i++)
- if ((1 << i) & newsegs)
- if (prepare_low_seg_for_htlb(mm, i) != 0)
+ for (i = 0; i < NUM_LOW_AREAS; i++)
+ if ((1 << i) & newareas)
+ if (prepare_low_area_for_htlb(mm, i) != 0)
return -EBUSY;
- mm->context.htlb_segs |= newsegs;
+ mm->context.low_htlb_areas |= newareas;
/* update the paca copy of the context struct */
get_paca()->context = mm->context;
@@ -215,29 +226,63 @@ static int open_low_hpage_segs(struct mm_struct *mm, u16 newsegs)
/* the context change must make it to memory before the flush,
* so that further SLB misses do the right thing. */
mb();
- on_each_cpu(flush_segments, (void *)(unsigned long)newsegs, 0, 1);
+ on_each_cpu(flush_low_segments, (void *)(unsigned long)newareas, 0, 1);
+
+ return 0;
+}
+
+static int open_high_hpage_areas(struct mm_struct *mm, u16 newareas)
+{
+ unsigned long i;
+
+ BUILD_BUG_ON((sizeof(newareas)*8) != NUM_HIGH_AREAS);
+ BUILD_BUG_ON((sizeof(mm->context.high_htlb_areas)*8)
+ != NUM_HIGH_AREAS);
+
+ newareas &= ~(mm->context.high_htlb_areas);
+ if (! newareas)
+ return 0; /* The areas we want are already open */
+
+ for (i = 0; i < NUM_HIGH_AREAS; i++)
+ if ((1 << i) & newareas)
+ if (prepare_high_area_for_htlb(mm, i) != 0)
+ return -EBUSY;
+
+ mm->context.high_htlb_areas |= newareas;
+
+ /* update the paca copy of the context struct */
+ get_paca()->context = mm->context;
+
+ /* the context change must make it to memory before the flush,
+ * so that further SLB misses do the right thing. */
+ mb();
+ on_each_cpu(flush_high_segments, (void *)(unsigned long)newareas, 0, 1);
return 0;
}
int prepare_hugepage_range(unsigned long addr, unsigned long len)
{
- if (within_hugepage_high_range(addr, len))
- return 0;
- else if ((addr < 0x100000000UL) && ((addr+len) < 0x100000000UL)) {
- int err;
- /* Yes, we need both tests, in case addr+len overflows
- * 64-bit arithmetic */
- err = open_low_hpage_segs(current->mm,
+ int err;
+
+ if ( (addr+len) < addr )
+ return -EINVAL;
+
+ if ((addr + len) < 0x100000000UL)
+ err = open_low_hpage_areas(current->mm,
LOW_ESID_MASK(addr, len));
- if (err)
- printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)"
- " failed (segs: 0x%04hx)\n", addr, len,
- LOW_ESID_MASK(addr, len));
+ else
+ err = open_high_hpage_areas(current->mm,
+ HTLB_AREA_MASK(addr, len));
+ if (err) {
+ printk(KERN_DEBUG "prepare_hugepage_range(%lx, %lx)"
+ " failed (lowmask: 0x%04hx, highmask: 0x%04hx)\n",
+ addr, len,
+ LOW_ESID_MASK(addr, len), HTLB_AREA_MASK(addr, len));
return err;
}
- return -EINVAL;
+ return 0;
}
struct page *
@@ -309,8 +354,8 @@ full_search:
vma = find_vma(mm, addr);
continue;
}
- if (touches_hugepage_high_range(addr, len)) {
- addr = TASK_HPAGE_END;
+ if (touches_hugepage_high_range(mm, addr, len)) {
+ addr = ALIGN(addr+1, 1UL<<HTLB_AREA_SHIFT);
vma = find_vma(mm, addr);
continue;
}
@@ -389,8 +434,9 @@ hugepage_recheck:
if (touches_hugepage_low_range(mm, addr, len)) {
addr = (addr & ((~0) << SID_SHIFT)) - len;
goto hugepage_recheck;
- } else if (touches_hugepage_high_range(addr, len)) {
- addr = TASK_HPAGE_BASE - len;
+ } else if (touches_hugepage_high_range(mm, addr, len)) {
+ addr = (addr & ((~0UL) << HTLB_AREA_SHIFT)) - len;
+ goto hugepage_recheck;
}
/*
@@ -481,23 +527,28 @@ static unsigned long htlb_get_low_area(unsigned long len, u16 segmask)
return -ENOMEM;
}
-static unsigned long htlb_get_high_area(unsigned long len)
+static unsigned long htlb_get_high_area(unsigned long len, u16 areamask)
{
- unsigned long addr = TASK_HPAGE_BASE;
+ unsigned long addr = 0x100000000UL;
struct vm_area_struct *vma;
vma = find_vma(current->mm, addr);
- for (vma = find_vma(current->mm, addr);
- addr + len <= TASK_HPAGE_END;
- vma = vma->vm_next) {
+ while (addr + len <= TASK_SIZE_USER64) {
BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
- BUG_ON(! within_hugepage_high_range(addr, len));
+
+ if (! __within_hugepage_high_range(addr, len, areamask)) {
+ addr = ALIGN(addr+1, 1UL<<HTLB_AREA_SHIFT);
+ vma = find_vma(current->mm, addr);
+ continue;
+ }
if (!vma || (addr + len) <= vma->vm_start)
return addr;
addr = ALIGN(vma->vm_end, HPAGE_SIZE);
- /* Because we're in a hugepage region, this alignment
- * should not skip us over any VMAs */
+ /* Depending on segmask this might not be a confirmed
+ * hugepage region, so the ALIGN could have skipped
+ * some VMAs */
+ vma = find_vma(current->mm, addr);
}
return -ENOMEM;
@@ -507,6 +558,9 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
unsigned long len, unsigned long pgoff,
unsigned long flags)
{
+ int lastshift;
+ u16 areamask, curareas;
+
if (len & ~HPAGE_MASK)
return -EINVAL;
@@ -514,67 +568,49 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
return -EINVAL;
if (test_thread_flag(TIF_32BIT)) {
- int lastshift = 0;
- u16 segmask, cursegs = current->mm->context.htlb_segs;
+ curareas = current->mm->context.low_htlb_areas;
/* First see if we can do the mapping in the existing
- * low hpage segments */
- addr = htlb_get_low_area(len, cursegs);
+ * low areas */
+ addr = htlb_get_low_area(len, curareas);
if (addr != -ENOMEM)
return addr;
- for (segmask = LOW_ESID_MASK(0x100000000UL-len, len);
- ! lastshift; segmask >>=1) {
- if (segmask & 1)
+ lastshift = 0;
+ for (areamask = LOW_ESID_MASK(0x100000000UL-len, len);
+ ! lastshift; areamask >>=1) {
+ if (areamask & 1)
lastshift = 1;
- addr = htlb_get_low_area(len, cursegs | segmask);
+ addr = htlb_get_low_area(len, curareas | areamask);
if ((addr != -ENOMEM)
- && open_low_hpage_segs(current->mm, segmask) == 0)
+ && open_low_hpage_areas(current->mm, areamask) == 0)
return addr;
}
- printk(KERN_DEBUG "hugetlb_get_unmapped_area() unable to open"
- " enough segments\n");
- return -ENOMEM;
} else {
- return htlb_get_high_area(len);
- }
-}
-
-void hugetlb_mm_free_pgd(struct mm_struct *mm)
-{
- int i;
- pgd_t *pgdir;
-
- spin_lock(&mm->page_table_lock);
-
- pgdir = mm->context.huge_pgdir;
- if (! pgdir)
- goto out;
-
- mm->context.huge_pgdir = NULL;
+ curareas = current->mm->context.high_htlb_areas;
- /* cleanup any hugepte pages leftover */
- for (i = 0; i < PTRS_PER_HUGEPGD; i++) {
- pud_t *pud = (pud_t *)(pgdir + i);
-
- if (! pud_none(*pud)) {
- pte_t *pte = (pte_t *)pud_page(*pud);
- struct page *ptepage = virt_to_page(pte);
+ /* First see if we can do the mapping in the existing
+ * high areas */
+ addr = htlb_get_high_area(len, curareas);
+ if (addr != -ENOMEM)
+ return addr;
- ptepage->mapping = NULL;
+ lastshift = 0;
+ for (areamask = HTLB_AREA_MASK(TASK_SIZE_USER64-len, len);
+ ! lastshift; areamask >>=1) {
+ if (areamask & 1)
+ lastshift = 1;
- BUG_ON(memcmp(pte, empty_zero_page, PAGE_SIZE));
- kmem_cache_free(zero_cache, pte);
+ addr = htlb_get_high_area(len, curareas | areamask);
+ if ((addr != -ENOMEM)
+ && open_high_hpage_areas(current->mm, areamask) == 0)
+ return addr;
}
- pud_clear(pud);
}
-
- BUG_ON(memcmp(pgdir, empty_zero_page, PAGE_SIZE));
- kmem_cache_free(zero_cache, pgdir);
-
- out:
- spin_unlock(&mm->page_table_lock);
+ printk(KERN_DEBUG "hugetlb_get_unmapped_area() unable to open"
+ " enough areas\n");
+ return -ENOMEM;
}
int hash_huge_page(struct mm_struct *mm, unsigned long access,