3 files changed, 172 insertions, 65 deletions

diff --git a/arch/ppc64/kernel/asm-offsets.c b/arch/ppc64/kernel/asm-offsets.c
index abb9e5b5da0..17e35d0fed0 100644
--- a/arch/ppc64/kernel/asm-offsets.c
+++ b/arch/ppc64/kernel/asm-offsets.c
@@ -94,7 +94,8 @@ int main(void)
         DEFINE(PACASLBCACHEPTR, offsetof(struct paca_struct, slb_cache_ptr));
         DEFINE(PACACONTEXTID, offsetof(struct paca_struct, context.id));
 #ifdef CONFIG_HUGETLB_PAGE
-        DEFINE(PACAHTLBSEGS, offsetof(struct paca_struct, context.htlb_segs));
+        DEFINE(PACALOWHTLBAREAS, offsetof(struct paca_struct, context.low_htlb_areas));
+        DEFINE(PACAHIGHHTLBAREAS, offsetof(struct paca_struct, context.high_htlb_areas));
 #endif /* CONFIG_HUGETLB_PAGE */
         DEFINE(PACADEFAULTDECR, offsetof(struct paca_struct, default_decr));
         DEFINE(PACA_EXGEN, offsetof(struct paca_struct, exgen));
diff --git a/arch/ppc64/mm/hugetlbpage.c b/arch/ppc64/mm/hugetlbpage.c
index a13e44230a6..e7833c80eb6 100644
--- a/arch/ppc64/mm/hugetlbpage.c
+++ b/arch/ppc64/mm/hugetlbpage.c
@@ -27,6 +27,9 @@
 
 #include <linux/sysctl.h>
 
+#define NUM_LOW_AREAS   (0x100000000UL >> SID_SHIFT)
+#define NUM_HIGH_AREAS  (PGTABLE_RANGE >> HTLB_AREA_SHIFT)
+
 /* Modelled after find_linux_pte() */
 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {
@@ -129,15 +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));
         }
@@ -145,13 +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)
+{
+        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 = seg << SID_SHIFT;
-        unsigned long end = (seg+1) << SID_SHIFT;
+        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);
@@ -161,20 +186,69 @@ 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.low_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_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.htlb_segs |= newsegs;
+        mm->context.high_htlb_areas |= newareas;
 
         /* update the paca copy of the context struct */
         get_paca()->context = mm->context;
@@ -182,29 +256,33 @@ 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_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 *
@@ -276,8 +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;
                 }
@@ -356,8 +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;
                 }
 
                 /*
@@ -448,23 +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;
@@ -474,6 +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;
 
@@ -481,31 +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);
+                curareas = current->mm->context.high_htlb_areas;
+
+                /* 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;
+
+                lastshift = 0;
+                for (areamask = HTLB_AREA_MASK(TASK_SIZE_USER64-len, len);
+                     ! lastshift; areamask >>=1) {
+                        if (areamask & 1)
+                                lastshift = 1;
+
+                        addr = htlb_get_high_area(len, curareas | areamask);
+                        if ((addr != -ENOMEM)
+                            && open_high_hpage_areas(current->mm, areamask) == 0)
+                                return addr;
+                }
         }
+        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,
diff --git a/arch/ppc64/mm/slb_low.S b/arch/ppc64/mm/slb_low.S
index f20fc52483a..bab255889c5 100644
--- a/arch/ppc64/mm/slb_low.S
+++ b/arch/ppc64/mm/slb_low.S
@@ -89,28 +89,29 @@ END_FTR_SECTION_IFSET(CPU_FTR_16M_PAGE)
         b       9f
 
 0:      /* user address: proto-VSID = context<<15 | ESID */
-        li      r11,SLB_VSID_USER
-
         srdi.   r9,r3,USER_ESID_BITS
         bne-    8f                      /* invalid ea bits set */
 
 #ifdef CONFIG_HUGETLB_PAGE
 BEGIN_FTR_SECTION
-        /* check against the hugepage ranges */
-        cmpldi  r3,(TASK_HPAGE_END>>SID_SHIFT)
-        bge     6f                      /* >= TASK_HPAGE_END */
-        cmpldi  r3,(TASK_HPAGE_BASE>>SID_SHIFT)
-        bge     5f                      /* TASK_HPAGE_BASE..TASK_HPAGE_END */
+        lhz     r9,PACAHIGHHTLBAREAS(r13)
+        srdi    r11,r3,(HTLB_AREA_SHIFT-SID_SHIFT)
+        srd     r9,r9,r11
+        andi.   r9,r9,1
+        bne     5f
+
+        li      r11,SLB_VSID_USER
+
         cmpldi  r3,16
-        bge     6f                      /* 4GB..TASK_HPAGE_BASE */
+        bge     6f
 
-        lhz     r9,PACAHTLBSEGS(r13)
+        lhz     r9,PACALOWHTLBAREAS(r13)
         srd     r9,r9,r3
         andi.   r9,r9,1
+
         beq     6f
 
-5:      /* this is a hugepage user address */
-        li      r11,(SLB_VSID_USER|SLB_VSID_L)
+5:      li      r11,SLB_VSID_USER|SLB_VSID_L
 END_FTR_SECTION_IFSET(CPU_FTR_16M_PAGE)
 #endif /* CONFIG_HUGETLB_PAGE */