* [PATCH 2/5] powerpc: Introduce address space "slices"
2007-05-08 6:27 [PATCH 0/5] This is my pending series for 2.6.22 Benjamin Herrenschmidt
2007-05-08 6:27 ` [PATCH 1/5] powerpc: Small fixes & cleanups in segment page size demotion Benjamin Herrenschmidt
@ 2007-05-08 6:27 ` Benjamin Herrenschmidt
2007-05-08 6:27 ` [PATCH 3/5] powerpc: Add ability to 4K kernel to hash in 64K pages Benjamin Herrenschmidt
` (2 subsequent siblings)
4 siblings, 0 replies; 9+ messages in thread
From: Benjamin Herrenschmidt @ 2007-05-08 6:27 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Hugh Dickins, Paul Mackerras
The basic issue is to be able to do what hugetlbfs does but with
different page sizes for some other special filesystems, more
specifically, my need is:
- Huge pages
- SPE local store mappings using 64K pages on a 4K base page size
kernel on Cell
- Some special 4K segments in 64K pages kernels for mapping a dodgy
specie of powerpc specific infiniband hardware that requires 4K MMU
mappings for various reasons I won't explain here.
The main issues are:
- To maintain/keep track of the page size per "segments" (as we can
only have one page size per segment on powerpc, which are 256MB
divisions of the address space).
- To make sure special mappings stay within their alloted
"segments" (including MAP_FIXED crap)
- To make sure everybody else doesn't mmap/brk/grow_stack into a
"segment" that is used for a special mapping
Some of the necessary mecanisms to handle that were present in the
hugetlbfs code, but mostly in ways not suitable for anything else.
The patch relies on some changes to the generic get_unmapped_area()
that just got merged. It still hijacks hugetlb callbacks here or
there as the generic code hasn't been entirely cleaned up yet but
that shouldn't be a problem.
So what is a slice ? Well, I re-used the mecanism used formerly by our
hugetlbfs implementation which divides the address space in
"meta-segments" which I called "slices". The division is done using
256MB slices below 4G, and 1T slices above. Thus the address space is
divided currently into 16 "low" slices and 16 "high" slices. (Special
case: high slice 0 is the area between 4G and 1T).
Doing so simplifies significantly the tracking of segments and avoid
having to keep track of all the 256MB segments in the address space.
While I used the "concepts" of hugetlbfs, I mostly re-implemented
everything in a more generic way and "ported" hugetlbfs to it.
slices can have an associated page size, which is encoded in the mmu
context and used by the SLB miss handler to set the segment sizes. The
hash code currently doesn't care, it has a specific check for hugepages,
though I might add a mecanism to provide per-slice hash mapping
functions in the future.
The slice code provide a pair of "generic" get_unmapped_area() (bottomup
and topdown) functions that should work with any slice size. There is
some trickyness here so I would appreciate people to have a look at the
implementation of these and let me know if I got something wrong.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/Kconfig | 5
arch/powerpc/kernel/asm-offsets.c | 16
arch/powerpc/mm/Makefile | 1
arch/powerpc/mm/hash_utils_64.c | 20 -
arch/powerpc/mm/hugetlbpage.c | 548 ----------------------------
arch/powerpc/mm/mmu_context_64.c | 10
arch/powerpc/mm/slb.c | 11
arch/powerpc/mm/slb_low.S | 54 +-
arch/powerpc/mm/slice.c | 633 +++++++++++++++++++++++++++++++++
arch/powerpc/platforms/cell/spu_base.c | 9
include/asm-powerpc/mmu-hash64.h | 11
include/asm-powerpc/paca.h | 2
include/asm-powerpc/page_64.h | 88 ++--
13 files changed, 771 insertions(+), 637 deletions(-)
Index: linux-cell/arch/powerpc/Kconfig
===================================================================
--- linux-cell.orig/arch/powerpc/Kconfig 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/Kconfig 2007-05-08 15:27:52.000000000 +1000
@@ -338,6 +338,11 @@ config PPC_STD_MMU_32
def_bool y
depends on PPC_STD_MMU && PPC32
+config PPC_MM_SLICES
+ bool
+ default y if HUGETLB_PAGE
+ default n
+
config VIRT_CPU_ACCOUNTING
bool "Deterministic task and CPU time accounting"
depends on PPC64
Index: linux-cell/include/asm-powerpc/paca.h
===================================================================
--- linux-cell.orig/include/asm-powerpc/paca.h 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/include/asm-powerpc/paca.h 2007-05-08 15:27:52.000000000 +1000
@@ -83,8 +83,8 @@ struct paca_struct {
mm_context_t context;
u16 vmalloc_sllp;
- u16 slb_cache[SLB_CACHE_ENTRIES];
u16 slb_cache_ptr;
+ u16 slb_cache[SLB_CACHE_ENTRIES];
/*
* then miscellaneous read-write fields
Index: linux-cell/include/asm-powerpc/page_64.h
===================================================================
--- linux-cell.orig/include/asm-powerpc/page_64.h 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/include/asm-powerpc/page_64.h 2007-05-08 15:27:52.000000000 +1000
@@ -88,57 +88,55 @@ extern unsigned int HPAGE_SHIFT;
#endif /* __ASSEMBLY__ */
-#ifdef CONFIG_HUGETLB_PAGE
+#ifdef CONFIG_PPC_MM_SLICES
-#define HTLB_AREA_SHIFT 40
-#define HTLB_AREA_SIZE (1UL << HTLB_AREA_SHIFT)
-#define GET_HTLB_AREA(x) ((x) >> HTLB_AREA_SHIFT)
-
-#define LOW_ESID_MASK(addr, len) \
- (((1U << (GET_ESID(min((addr)+(len)-1, 0x100000000UL))+1)) \
- - (1U << GET_ESID(min((addr), 0x100000000UL)))) & 0xffff)
-#define HTLB_AREA_MASK(addr, len) (((1U << (GET_HTLB_AREA(addr+len-1)+1)) \
- - (1U << GET_HTLB_AREA(addr))) & 0xffff)
+#define SLICE_LOW_SHIFT 28
+#define SLICE_HIGH_SHIFT 40
-#define ARCH_HAS_HUGEPAGE_ONLY_RANGE
-#define ARCH_HAS_HUGETLB_FREE_PGD_RANGE
-#define ARCH_HAS_PREPARE_HUGEPAGE_RANGE
-#define ARCH_HAS_SETCLEAR_HUGE_PTE
+#define SLICE_LOW_TOP (0x100000000ul)
+#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
+#define SLICE_NUM_HIGH (PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
-#define touches_hugepage_low_range(mm, addr, len) \
- (((addr) < 0x100000000UL) \
- && (LOW_ESID_MASK((addr), (len)) & (mm)->context.low_htlb_areas))
-#define touches_hugepage_high_range(mm, addr, len) \
- ((((addr) + (len)) > 0x100000000UL) \
- && (HTLB_AREA_MASK((addr), (len)) & (mm)->context.high_htlb_areas))
-
-#define __within_hugepage_low_range(addr, len, segmask) \
- ( (((addr)+(len)) <= 0x100000000UL) \
- && ((LOW_ESID_MASK((addr), (len)) | (segmask)) == (segmask)))
-#define within_hugepage_low_range(addr, len) \
- __within_hugepage_low_range((addr), (len), \
- current->mm->context.low_htlb_areas)
-#define __within_hugepage_high_range(addr, len, zonemask) \
- ( ((addr) >= 0x100000000UL) \
- && ((HTLB_AREA_MASK((addr), (len)) | (zonemask)) == (zonemask)))
-#define within_hugepage_high_range(addr, len) \
- __within_hugepage_high_range((addr), (len), \
- current->mm->context.high_htlb_areas)
-
-#define is_hugepage_only_range(mm, addr, len) \
- (touches_hugepage_high_range((mm), (addr), (len)) || \
- touches_hugepage_low_range((mm), (addr), (len)))
-#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
+#define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
-#define in_hugepage_area(context, addr) \
- (cpu_has_feature(CPU_FTR_16M_PAGE) && \
- ( ( (addr) >= 0x100000000UL) \
- ? ((1 << GET_HTLB_AREA(addr)) & (context).high_htlb_areas) \
- : ((1 << GET_ESID(addr)) & (context).low_htlb_areas) ) )
+#ifndef __ASSEMBLY__
-#else /* !CONFIG_HUGETLB_PAGE */
+struct slice_mask {
+ u16 low_slices;
+ u16 high_slices;
+};
-#define in_hugepage_area(mm, addr) 0
+struct mm_struct;
+
+extern unsigned long slice_get_unmapped_area(unsigned long addr,
+ unsigned long len,
+ unsigned long flags,
+ unsigned int psize,
+ int topdown,
+ int use_cache);
+
+extern unsigned int get_slice_psize(struct mm_struct *mm,
+ unsigned long addr);
+
+extern void slice_init_context(struct mm_struct *mm, unsigned int psize);
+extern void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
+
+#define ARCH_HAS_HUGEPAGE_ONLY_RANGE
+extern int is_hugepage_only_range(struct mm_struct *m,
+ unsigned long addr,
+ unsigned long len);
+
+#endif /* __ASSEMBLY__ */
+#else
+#define slice_init()
+#endif /* CONFIG_PPC_MM_SLICES */
+
+#ifdef CONFIG_HUGETLB_PAGE
+
+#define ARCH_HAS_HUGETLB_FREE_PGD_RANGE
+#define ARCH_HAS_SETCLEAR_HUGE_PTE
+#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
#endif /* !CONFIG_HUGETLB_PAGE */
Index: linux-cell/arch/powerpc/mm/Makefile
===================================================================
--- linux-cell.orig/arch/powerpc/mm/Makefile 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/mm/Makefile 2007-05-08 15:27:52.000000000 +1000
@@ -18,4 +18,5 @@ obj-$(CONFIG_40x) += 4xx_mmu.o
obj-$(CONFIG_44x) += 44x_mmu.o
obj-$(CONFIG_FSL_BOOKE) += fsl_booke_mmu.o
obj-$(CONFIG_NEED_MULTIPLE_NODES) += numa.o
+obj-$(CONFIG_PPC_MM_SLICES) += slice.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
Index: linux-cell/arch/powerpc/mm/slice.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-cell/arch/powerpc/mm/slice.c 2007-05-08 15:27:52.000000000 +1000
@@ -0,0 +1,633 @@
+/*
+ * address space "slices" (meta-segments) support
+ *
+ * Copyright (C) 2007 Benjamin Herrenschmidt, IBM Corporation.
+ *
+ * Based on hugetlb implementation
+ *
+ * Copyright (C) 2003 David Gibson, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/module.h>
+#include <asm/mman.h>
+#include <asm/mmu.h>
+#include <asm/spu.h>
+
+static spinlock_t slice_convert_lock = SPIN_LOCK_UNLOCKED;
+
+
+#ifdef DEBUG
+int _slice_debug = 1;
+
+static void slice_print_mask(const char *label, struct slice_mask mask)
+{
+ char *p, buf[16 + 3 + 16 + 1];
+ int i;
+
+ if (!_slice_debug)
+ return;
+ p = buf;
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ *(p++) = (mask.low_slices & (1 << i)) ? '1' : '0';
+ *(p++) = ' ';
+ *(p++) = '-';
+ *(p++) = ' ';
+ for (i = 0; i < SLICE_NUM_HIGH; i++)
+ *(p++) = (mask.high_slices & (1 << i)) ? '1' : '0';
+ *(p++) = 0;
+
+ printk(KERN_DEBUG "%s:%s\n", label, buf);
+}
+
+#define slice_dbg(fmt...) do { if (_slice_debug) pr_debug(fmt); } while(0)
+
+#else
+
+static void slice_print_mask(const char *label, struct slice_mask mask) {}
+#define slice_dbg(fmt...)
+
+#endif
+
+static struct slice_mask slice_range_to_mask(unsigned long start,
+ unsigned long len)
+{
+ unsigned long end = start + len - 1;
+ struct slice_mask ret = { 0, 0 };
+
+ if (start < SLICE_LOW_TOP) {
+ unsigned long mend = min(end, SLICE_LOW_TOP);
+ unsigned long mstart = min(start, SLICE_LOW_TOP);
+
+ ret.low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
+ - (1u << GET_LOW_SLICE_INDEX(mstart));
+ }
+
+ if ((start + len) > SLICE_LOW_TOP)
+ ret.high_slices = (1u << (GET_HIGH_SLICE_INDEX(end) + 1))
+ - (1u << GET_HIGH_SLICE_INDEX(start));
+
+ return ret;
+}
+
+static int slice_area_is_free(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ struct vm_area_struct *vma;
+
+ if ((mm->task_size - len) < addr)
+ return 0;
+ vma = find_vma(mm, addr);
+ return (!vma || (addr + len) <= vma->vm_start);
+}
+
+static int slice_low_has_vma(struct mm_struct *mm, unsigned long slice)
+{
+ return !slice_area_is_free(mm, slice << SLICE_LOW_SHIFT,
+ 1ul << SLICE_LOW_SHIFT);
+}
+
+static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
+{
+ unsigned long start = slice << SLICE_HIGH_SHIFT;
+ unsigned long end = start + (1ul << SLICE_HIGH_SHIFT);
+
+ /* Hack, so that each addresses is controlled by exactly one
+ * of the high or low area bitmaps, the first high area starts
+ * at 4GB, not 0 */
+ if (start == 0)
+ start = SLICE_LOW_TOP;
+
+ return !slice_area_is_free(mm, start, end - start);
+}
+
+static struct slice_mask slice_mask_for_free(struct mm_struct *mm)
+{
+ struct slice_mask ret = { 0, 0 };
+ unsigned long i;
+
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ if (!slice_low_has_vma(mm, i))
+ ret.low_slices |= 1u << i;
+
+ if (mm->task_size <= SLICE_LOW_TOP)
+ return ret;
+
+ for (i = 0; i < SLICE_NUM_HIGH; i++)
+ if (!slice_high_has_vma(mm, i))
+ ret.high_slices |= 1u << i;
+
+ return ret;
+}
+
+static struct slice_mask slice_mask_for_size(struct mm_struct *mm, int psize)
+{
+ struct slice_mask ret = { 0, 0 };
+ unsigned long i;
+ u64 psizes;
+
+ psizes = mm->context.low_slices_psize;
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ if (((psizes >> (i * 4)) & 0xf) == psize)
+ ret.low_slices |= 1u << i;
+
+ psizes = mm->context.high_slices_psize;
+ for (i = 0; i < SLICE_NUM_HIGH; i++)
+ if (((psizes >> (i * 4)) & 0xf) == psize)
+ ret.high_slices |= 1u << i;
+
+ return ret;
+}
+
+static int slice_check_fit(struct slice_mask mask, struct slice_mask available)
+{
+ return (mask.low_slices & available.low_slices) == mask.low_slices &&
+ (mask.high_slices & available.high_slices) == mask.high_slices;
+}
+
+static void slice_flush_segments(void *parm)
+{
+ struct mm_struct *mm = parm;
+ unsigned long flags;
+
+ if (mm != current->active_mm)
+ return;
+
+ /* update the paca copy of the context struct */
+ get_paca()->context = current->active_mm->context;
+
+ local_irq_save(flags);
+ slb_flush_and_rebolt();
+ local_irq_restore(flags);
+}
+
+static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
+{
+ /* Write the new slice psize bits */
+ u64 lpsizes, hpsizes;
+ unsigned long i, flags;
+
+ slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
+ slice_print_mask(" mask", mask);
+
+ /* We need to use a spinlock here to protect against
+ * concurrent 64k -> 4k demotion ...
+ */
+ spin_lock_irqsave(&slice_convert_lock, flags);
+
+ lpsizes = mm->context.low_slices_psize;
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ if (mask.low_slices & (1u << i))
+ lpsizes = (lpsizes & ~(0xful << (i * 4))) |
+ (((unsigned long)psize) << (i * 4));
+
+ hpsizes = mm->context.high_slices_psize;
+ for (i = 0; i < SLICE_NUM_HIGH; i++)
+ if (mask.high_slices & (1u << i))
+ hpsizes = (hpsizes & ~(0xful << (i * 4))) |
+ (((unsigned long)psize) << (i * 4));
+
+ mm->context.low_slices_psize = lpsizes;
+ mm->context.high_slices_psize = hpsizes;
+
+ slice_dbg(" lsps=%lx, hsps=%lx\n",
+ mm->context.low_slices_psize,
+ mm->context.high_slices_psize);
+
+ spin_unlock_irqrestore(&slice_convert_lock, flags);
+ mb();
+
+ /* XXX this is sub-optimal but will do for now */
+ on_each_cpu(slice_flush_segments, mm, 0, 1);
+#ifdef CONFIG_SPU_BASE
+ spu_flush_all_slbs(mm);
+#endif
+}
+
+static unsigned long slice_find_area_bottomup(struct mm_struct *mm,
+ unsigned long len,
+ struct slice_mask available,
+ int psize, int use_cache)
+{
+ struct vm_area_struct *vma;
+ unsigned long start_addr, addr;
+ struct slice_mask mask;
+ int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+
+ if (use_cache) {
+ if (len <= mm->cached_hole_size) {
+ start_addr = addr = TASK_UNMAPPED_BASE;
+ mm->cached_hole_size = 0;
+ } else
+ start_addr = addr = mm->free_area_cache;
+ } else
+ start_addr = addr = TASK_UNMAPPED_BASE;
+
+full_search:
+ for (;;) {
+ addr = _ALIGN_UP(addr, 1ul << pshift);
+ if ((TASK_SIZE - len) < addr)
+ break;
+ vma = find_vma(mm, addr);
+ BUG_ON(vma && (addr >= vma->vm_end));
+
+ mask = slice_range_to_mask(addr, len);
+ if (!slice_check_fit(mask, available)) {
+ if (addr < SLICE_LOW_TOP)
+ addr = _ALIGN_UP(addr + 1, 1ul << SLICE_LOW_SHIFT);
+ else
+ addr = _ALIGN_UP(addr + 1, 1ul << SLICE_HIGH_SHIFT);
+ continue;
+ }
+ if (!vma || addr + len <= vma->vm_start) {
+ /*
+ * Remember the place where we stopped the search:
+ */
+ if (use_cache)
+ mm->free_area_cache = addr + len;
+ return addr;
+ }
+ if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start)
+ mm->cached_hole_size = vma->vm_start - addr;
+ addr = vma->vm_end;
+ }
+
+ /* Make sure we didn't miss any holes */
+ if (use_cache && start_addr != TASK_UNMAPPED_BASE) {
+ start_addr = addr = TASK_UNMAPPED_BASE;
+ mm->cached_hole_size = 0;
+ goto full_search;
+ }
+ return -ENOMEM;
+}
+
+static unsigned long slice_find_area_topdown(struct mm_struct *mm,
+ unsigned long len,
+ struct slice_mask available,
+ int psize, int use_cache)
+{
+ struct vm_area_struct *vma;
+ unsigned long addr;
+ struct slice_mask mask;
+ int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+
+ /* check if free_area_cache is useful for us */
+ if (use_cache) {
+ if (len <= mm->cached_hole_size) {
+ mm->cached_hole_size = 0;
+ mm->free_area_cache = mm->mmap_base;
+ }
+
+ /* either no address requested or can't fit in requested
+ * address hole
+ */
+ addr = mm->free_area_cache;
+
+ /* make sure it can fit in the remaining address space */
+ if (addr > len) {
+ addr = _ALIGN_DOWN(addr - len, 1ul << pshift);
+ mask = slice_range_to_mask(addr, len);
+ if (slice_check_fit(mask, available) &&
+ slice_area_is_free(mm, addr, len))
+ /* remember the address as a hint for
+ * next time
+ */
+ return (mm->free_area_cache = addr);
+ }
+ }
+
+ addr = mm->mmap_base;
+ while (addr > len) {
+ /* Go down by chunk size */
+ addr = _ALIGN_DOWN(addr - len, 1ul << pshift);
+
+ /* Check for hit with different page size */
+ mask = slice_range_to_mask(addr, len);
+ if (!slice_check_fit(mask, available)) {
+ if (addr < SLICE_LOW_TOP)
+ addr = _ALIGN_DOWN(addr, 1ul << SLICE_LOW_SHIFT);
+ else if (addr < (1ul << SLICE_HIGH_SHIFT))
+ addr = SLICE_LOW_TOP;
+ else
+ addr = _ALIGN_DOWN(addr, 1ul << SLICE_HIGH_SHIFT);
+ continue;
+ }
+
+ /*
+ * Lookup failure means no vma is above this address,
+ * else if new region fits below vma->vm_start,
+ * return with success:
+ */
+ vma = find_vma(mm, addr);
+ if (!vma || (addr + len) <= vma->vm_start) {
+ /* remember the address as a hint for next time */
+ if (use_cache)
+ mm->free_area_cache = addr;
+ return addr;
+ }
+
+ /* remember the largest hole we saw so far */
+ if (use_cache && (addr + mm->cached_hole_size) < vma->vm_start)
+ mm->cached_hole_size = vma->vm_start - addr;
+
+ /* try just below the current vma->vm_start */
+ addr = vma->vm_start;
+ }
+
+ /*
+ * A failed mmap() very likely causes application failure,
+ * so fall back to the bottom-up function here. This scenario
+ * can happen with large stack limits and large mmap()
+ * allocations.
+ */
+ addr = slice_find_area_bottomup(mm, len, available, psize, 0);
+
+ /*
+ * Restore the topdown base:
+ */
+ if (use_cache) {
+ mm->free_area_cache = mm->mmap_base;
+ mm->cached_hole_size = ~0UL;
+ }
+
+ return addr;
+}
+
+
+static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len,
+ struct slice_mask mask, int psize,
+ int topdown, int use_cache)
+{
+ if (topdown)
+ return slice_find_area_topdown(mm, len, mask, psize, use_cache);
+ else
+ return slice_find_area_bottomup(mm, len, mask, psize, use_cache);
+}
+
+unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
+ unsigned long flags, unsigned int psize,
+ int topdown, int use_cache)
+{
+ struct slice_mask mask;
+ struct slice_mask good_mask;
+ struct slice_mask potential_mask = {0,0} /* silence stupid warning */;
+ int pmask_set = 0;
+ int fixed = (flags & MAP_FIXED);
+ int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT);
+ struct mm_struct *mm = current->mm;
+
+ /* Sanity checks */
+ BUG_ON(mm->task_size == 0);
+
+ slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize);
+ slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d, use_cache=%d\n",
+ addr, len, flags, topdown, use_cache);
+
+ if (len > mm->task_size)
+ return -ENOMEM;
+ if (fixed && (addr & ((1ul << pshift) - 1)))
+ return -EINVAL;
+ if (fixed && addr > (mm->task_size - len))
+ return -EINVAL;
+
+ /* If hint, make sure it matches our alignment restrictions */
+ if (!fixed && addr) {
+ addr = _ALIGN_UP(addr, 1ul << pshift);
+ slice_dbg(" aligned addr=%lx\n", addr);
+ }
+
+ /* First makeup a "good" mask of slices that have the right size
+ * already
+ */
+ good_mask = slice_mask_for_size(mm, psize);
+ slice_print_mask(" good_mask", good_mask);
+
+ /* First check hint if it's valid or if we have MAP_FIXED */
+ if ((addr != 0 || fixed) && (mm->task_size - len) >= addr) {
+
+ /* Don't bother with hint if it overlaps a VMA */
+ if (!fixed && !slice_area_is_free(mm, addr, len))
+ goto search;
+
+ /* Build a mask for the requested range */
+ mask = slice_range_to_mask(addr, len);
+ slice_print_mask(" mask", mask);
+
+ /* Check if we fit in the good mask. If we do, we just return,
+ * nothing else to do
+ */
+ if (slice_check_fit(mask, good_mask)) {
+ slice_dbg(" fits good !\n");
+ return addr;
+ }
+
+ /* We don't fit in the good mask, check what other slices are
+ * empty and thus can be converted
+ */
+ potential_mask = slice_mask_for_free(mm);
+ potential_mask.low_slices |= good_mask.low_slices;
+ potential_mask.high_slices |= good_mask.high_slices;
+ pmask_set = 1;
+ slice_print_mask(" potential", potential_mask);
+ if (slice_check_fit(mask, potential_mask)) {
+ slice_dbg(" fits potential !\n");
+ goto convert;
+ }
+ }
+
+ /* If we have MAP_FIXED and failed the above step, then error out */
+ if (fixed)
+ return -EBUSY;
+
+ search:
+ slice_dbg(" search...\n");
+
+ /* Now let's see if we can find something in the existing slices
+ * for that size
+ */
+ addr = slice_find_area(mm, len, good_mask, psize, topdown, use_cache);
+ if (addr != -ENOMEM) {
+ /* Found within the good mask, we don't have to setup,
+ * we thus return directly
+ */
+ slice_dbg(" found area at 0x%lx\n", addr);
+ return addr;
+ }
+
+ /* Won't fit, check what can be converted */
+ if (!pmask_set) {
+ potential_mask = slice_mask_for_free(mm);
+ potential_mask.low_slices |= good_mask.low_slices;
+ potential_mask.high_slices |= good_mask.high_slices;
+ pmask_set = 1;
+ slice_print_mask(" potential", potential_mask);
+ }
+
+ /* Now let's see if we can find something in the existing slices
+ * for that size
+ */
+ addr = slice_find_area(mm, len, potential_mask, psize, topdown,
+ use_cache);
+ if (addr == -ENOMEM)
+ return -ENOMEM;
+
+ mask = slice_range_to_mask(addr, len);
+ slice_dbg(" found potential area at 0x%lx\n", addr);
+ slice_print_mask(" mask", mask);
+
+ convert:
+ slice_convert(mm, mask, psize);
+ return addr;
+
+}
+EXPORT_SYMBOL_GPL(slice_get_unmapped_area);
+
+unsigned long arch_get_unmapped_area(struct file *filp,
+ unsigned long addr,
+ unsigned long len,
+ unsigned long pgoff,
+ unsigned long flags)
+{
+ return slice_get_unmapped_area(addr, len, flags,
+ current->mm->context.user_psize,
+ 0, 1);
+}
+
+unsigned long arch_get_unmapped_area_topdown(struct file *filp,
+ const unsigned long addr0,
+ const unsigned long len,
+ const unsigned long pgoff,
+ const unsigned long flags)
+{
+ return slice_get_unmapped_area(addr0, len, flags,
+ current->mm->context.user_psize,
+ 1, 1);
+}
+
+unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
+{
+ u64 psizes;
+ int index;
+
+ if (addr < SLICE_LOW_TOP) {
+ psizes = mm->context.low_slices_psize;
+ index = GET_LOW_SLICE_INDEX(addr);
+ } else {
+ psizes = mm->context.high_slices_psize;
+ index = GET_HIGH_SLICE_INDEX(addr);
+ }
+
+ return (psizes >> (index * 4)) & 0xf;
+}
+EXPORT_SYMBOL_GPL(get_slice_psize);
+
+/*
+ * This is called by hash_page when it needs to do a lazy conversion of
+ * an address space from real 64K pages to combo 4K pages (typically
+ * when hitting a non cacheable mapping on a processor or hypervisor
+ * that won't allow them for 64K pages).
+ *
+ * This is also called in init_new_context() to change back the user
+ * psize from whatever the parent context had it set to
+ *
+ * This function will only change the content of the {low,high)_slice_psize
+ * masks, it will not flush SLBs as this shall be handled lazily by the
+ * caller.
+ */
+void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
+{
+ unsigned long flags, lpsizes, hpsizes;
+ unsigned int old_psize;
+ int i;
+
+ slice_dbg("slice_set_user_psize(mm=%p, psize=%d)\n", mm, psize);
+
+ spin_lock_irqsave(&slice_convert_lock, flags);
+
+ old_psize = mm->context.user_psize;
+ slice_dbg(" old_psize=%d\n", old_psize);
+ if (old_psize == psize)
+ goto bail;
+
+ mm->context.user_psize = psize;
+ wmb();
+
+ lpsizes = mm->context.low_slices_psize;
+ for (i = 0; i < SLICE_NUM_LOW; i++)
+ if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
+ lpsizes = (lpsizes & ~(0xful << (i * 4))) |
+ (((unsigned long)psize) << (i * 4));
+
+ hpsizes = mm->context.high_slices_psize;
+ for (i = 0; i < SLICE_NUM_HIGH; i++)
+ if (((hpsizes >> (i * 4)) & 0xf) == old_psize)
+ hpsizes = (hpsizes & ~(0xful << (i * 4))) |
+ (((unsigned long)psize) << (i * 4));
+
+ mm->context.low_slices_psize = lpsizes;
+ mm->context.high_slices_psize = hpsizes;
+
+ slice_dbg(" lsps=%lx, hsps=%lx\n",
+ mm->context.low_slices_psize,
+ mm->context.high_slices_psize);
+
+ bail:
+ spin_unlock_irqrestore(&slice_convert_lock, flags);
+}
+
+/*
+ * is_hugepage_only_range() is used by generic code to verify wether
+ * a normal mmap mapping (non hugetlbfs) is valid on a given area.
+ *
+ * until the generic code provides a more generic hook and/or starts
+ * calling arch get_unmapped_area for MAP_FIXED (which our implementation
+ * here knows how to deal with), we hijack it to keep standard mappings
+ * away from us.
+ *
+ * because of that generic code limitation, MAP_FIXED mapping cannot
+ * "convert" back a slice with no VMAs to the standard page size, only
+ * get_unmapped_area() can. It would be possible to fix it here but I
+ * prefer working on fixing the generic code instead.
+ *
+ * WARNING: This will not work if hugetlbfs isn't enabled since the
+ * generic code will redefine that function as 0 in that. This is ok
+ * for now as we only use slices with hugetlbfs enabled. This should
+ * be fixed as the generic code gets fixed.
+ */
+int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr,
+ unsigned long len)
+{
+ struct slice_mask mask, available;
+
+ mask = slice_range_to_mask(addr, len);
+ available = slice_mask_for_size(mm, mm->context.user_psize);
+
+#if 0 /* too verbose */
+ slice_dbg("is_hugepage_only_range(mm=%p, addr=%lx, len=%lx)\n",
+ mm, addr, len);
+ slice_print_mask(" mask", mask);
+ slice_print_mask(" available", available);
+#endif
+ return !slice_check_fit(mask, available);
+}
+
Index: linux-cell/arch/powerpc/kernel/asm-offsets.c
===================================================================
--- linux-cell.orig/arch/powerpc/kernel/asm-offsets.c 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/kernel/asm-offsets.c 2007-05-08 15:27:52.000000000 +1000
@@ -122,12 +122,18 @@ int main(void)
DEFINE(PACASLBCACHE, offsetof(struct paca_struct, slb_cache));
DEFINE(PACASLBCACHEPTR, offsetof(struct paca_struct, slb_cache_ptr));
DEFINE(PACACONTEXTID, offsetof(struct paca_struct, context.id));
- DEFINE(PACACONTEXTSLLP, offsetof(struct paca_struct, context.sllp));
DEFINE(PACAVMALLOCSLLP, offsetof(struct paca_struct, vmalloc_sllp));
-#ifdef CONFIG_HUGETLB_PAGE
- DEFINE(PACALOWHTLBAREAS, offsetof(struct paca_struct, context.low_htlb_areas));
- DEFINE(PACAHIGHHTLBAREAS, offsetof(struct paca_struct, context.high_htlb_areas));
-#endif /* CONFIG_HUGETLB_PAGE */
+#ifdef CONFIG_PPC_MM_SLICES
+ DEFINE(PACALOWSLICESPSIZE, offsetof(struct paca_struct,
+ context.low_slices_psize));
+ DEFINE(PACAHIGHSLICEPSIZE, offsetof(struct paca_struct,
+ context.high_slices_psize));
+ DEFINE(MMUPSIZEDEFSIZE, sizeof(struct mmu_psize_def));
+ DEFINE(MMUPSIZESLLP, offsetof(struct mmu_psize_def, sllp));
+#else
+ DEFINE(PACACONTEXTSLLP, offsetof(struct paca_struct, context.sllp));
+
+#endif /* CONFIG_PPC_MM_SLICES */
DEFINE(PACA_EXGEN, offsetof(struct paca_struct, exgen));
DEFINE(PACA_EXMC, offsetof(struct paca_struct, exmc));
DEFINE(PACA_EXSLB, offsetof(struct paca_struct, exslb));
Index: linux-cell/arch/powerpc/mm/hugetlbpage.c
===================================================================
--- linux-cell.orig/arch/powerpc/mm/hugetlbpage.c 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/mm/hugetlbpage.c 2007-05-08 15:27:52.000000000 +1000
@@ -92,7 +92,7 @@ pte_t *huge_pte_offset(struct mm_struct
pgd_t *pg;
pud_t *pu;
- BUG_ON(! in_hugepage_area(mm->context, addr));
+ BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
addr &= HPAGE_MASK;
@@ -120,7 +120,7 @@ pte_t *huge_pte_alloc(struct mm_struct *
pud_t *pu;
hugepd_t *hpdp = NULL;
- BUG_ON(! in_hugepage_area(mm->context, addr));
+ BUG_ON(get_slice_psize(mm, addr) != mmu_huge_psize);
addr &= HPAGE_MASK;
@@ -303,7 +303,7 @@ void hugetlb_free_pgd_range(struct mmu_g
start = addr;
pgd = pgd_offset((*tlb)->mm, addr);
do {
- BUG_ON(! in_hugepage_area((*tlb)->mm->context, addr));
+ BUG_ON(get_slice_psize((*tlb)->mm, addr) != mmu_huge_psize);
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd))
continue;
@@ -332,203 +332,13 @@ pte_t huge_ptep_get_and_clear(struct mm_
return __pte(old);
}
-struct slb_flush_info {
- struct mm_struct *mm;
- u16 newareas;
-};
-
-static void flush_low_segments(void *parm)
-{
- struct slb_flush_info *fi = parm;
- unsigned long i;
-
- BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_LOW_AREAS);
-
- if (current->active_mm != fi->mm)
- return;
-
- /* Only need to do anything if this CPU is working in the same
- * mm as the one which has changed */
-
- /* update the paca copy of the context struct */
- get_paca()->context = current->active_mm->context;
-
- asm volatile("isync" : : : "memory");
- for (i = 0; i < NUM_LOW_AREAS; i++) {
- if (! (fi->newareas & (1U << i)))
- continue;
- asm volatile("slbie %0"
- : : "r" ((i << SID_SHIFT) | SLBIE_C));
- }
- asm volatile("isync" : : : "memory");
-}
-
-static void flush_high_segments(void *parm)
-{
- struct slb_flush_info *fi = parm;
- unsigned long i, j;
-
-
- BUILD_BUG_ON((sizeof(fi->newareas)*8) != NUM_HIGH_AREAS);
-
- if (current->active_mm != fi->mm)
- return;
-
- /* Only need to do anything if this CPU is working in the same
- * mm as the one which has changed */
-
- /* update the paca copy of the context struct */
- get_paca()->context = current->active_mm->context;
-
- asm volatile("isync" : : : "memory");
- for (i = 0; i < NUM_HIGH_AREAS; i++) {
- if (! (fi->newareas & (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)) | SLBIE_C));
- }
- 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(area >= NUM_LOW_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 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);
-
- /* Hack, so that each addresses is controlled by exactly one
- * of the high or low area bitmaps, the first high area starts
- * at 4GB, not 0 */
- if (start == 0)
- start = 0x100000000UL;
-
- /* 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;
- struct slb_flush_info fi;
-
- 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 < 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;
-
- /* the context change must make it to memory before the flush,
- * so that further SLB misses do the right thing. */
- mb();
-
- fi.mm = mm;
- fi.newareas = newareas;
- on_each_cpu(flush_low_segments, &fi, 0, 1);
-
- return 0;
-}
-
-static int open_high_hpage_areas(struct mm_struct *mm, u16 newareas)
-{
- struct slb_flush_info fi;
- 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;
-
- /* the context change must make it to memory before the flush,
- * so that further SLB misses do the right thing. */
- mb();
-
- fi.mm = mm;
- fi.newareas = newareas;
- on_each_cpu(flush_high_segments, &fi, 0, 1);
-
- return 0;
-}
-
-int prepare_hugepage_range(unsigned long addr, unsigned long len, pgoff_t pgoff)
-{
- int err = 0;
-
- if (pgoff & (~HPAGE_MASK >> PAGE_SHIFT))
- return -EINVAL;
- if (len & ~HPAGE_MASK)
- return -EINVAL;
- if (addr & ~HPAGE_MASK)
- return -EINVAL;
-
- if (addr < 0x100000000UL)
- err = open_low_hpage_areas(current->mm,
- LOW_ESID_MASK(addr, len));
- if ((addr + len) > 0x100000000UL)
- err = open_high_hpage_areas(current->mm,
- HTLB_AREA_MASK(addr, len));
-#ifdef CONFIG_SPE_BASE
- spu_flush_all_slbs(current->mm);
-#endif
- 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 0;
-}
-
struct page *
follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
{
pte_t *ptep;
struct page *page;
- if (! in_hugepage_area(mm->context, address))
+ if (get_slice_psize(mm, address) != mmu_huge_psize)
return ERR_PTR(-EINVAL);
ptep = huge_pte_offset(mm, address);
@@ -552,359 +362,13 @@ follow_huge_pmd(struct mm_struct *mm, un
return NULL;
}
-/* Because we have an exclusive hugepage region which lies within the
- * normal user address space, we have to take special measures to make
- * non-huge mmap()s evade the hugepage reserved regions. */
-unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
- unsigned long len, unsigned long pgoff,
- unsigned long flags)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- unsigned long start_addr;
-
- if (len > TASK_SIZE)
- return -ENOMEM;
-
- /* handle fixed mapping: prevent overlap with huge pages */
- if (flags & MAP_FIXED) {
- if (is_hugepage_only_range(mm, addr, len))
- return -EINVAL;
- return addr;
- }
-
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (((TASK_SIZE - len) >= addr)
- && (!vma || (addr+len) <= vma->vm_start)
- && !is_hugepage_only_range(mm, addr,len))
- return addr;
- }
- if (len > mm->cached_hole_size) {
- start_addr = addr = mm->free_area_cache;
- } else {
- start_addr = addr = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = 0;
- }
-
-full_search:
- vma = find_vma(mm, addr);
- while (TASK_SIZE - len >= addr) {
- BUG_ON(vma && (addr >= vma->vm_end));
-
- if (touches_hugepage_low_range(mm, addr, len)) {
- addr = ALIGN(addr+1, 1<<SID_SHIFT);
- vma = find_vma(mm, addr);
- continue;
- }
- if (touches_hugepage_high_range(mm, addr, len)) {
- addr = ALIGN(addr+1, 1UL<<HTLB_AREA_SHIFT);
- vma = find_vma(mm, addr);
- continue;
- }
- if (!vma || addr + len <= vma->vm_start) {
- /*
- * Remember the place where we stopped the search:
- */
- mm->free_area_cache = addr + len;
- return addr;
- }
- if (addr + mm->cached_hole_size < vma->vm_start)
- mm->cached_hole_size = vma->vm_start - addr;
- addr = vma->vm_end;
- vma = vma->vm_next;
- }
-
- /* Make sure we didn't miss any holes */
- if (start_addr != TASK_UNMAPPED_BASE) {
- start_addr = addr = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = 0;
- goto full_search;
- }
- return -ENOMEM;
-}
-
-/*
- * This mmap-allocator allocates new areas top-down from below the
- * stack's low limit (the base):
- *
- * Because we have an exclusive hugepage region which lies within the
- * normal user address space, we have to take special measures to make
- * non-huge mmap()s evade the hugepage reserved regions.
- */
-unsigned long
-arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
- const unsigned long len, const unsigned long pgoff,
- const unsigned long flags)
-{
- struct vm_area_struct *vma, *prev_vma;
- struct mm_struct *mm = current->mm;
- unsigned long base = mm->mmap_base, addr = addr0;
- unsigned long largest_hole = mm->cached_hole_size;
- int first_time = 1;
-
- /* requested length too big for entire address space */
- if (len > TASK_SIZE)
- return -ENOMEM;
-
- /* handle fixed mapping: prevent overlap with huge pages */
- if (flags & MAP_FIXED) {
- if (is_hugepage_only_range(mm, addr, len))
- return -EINVAL;
- return addr;
- }
-
- /* dont allow allocations above current base */
- if (mm->free_area_cache > base)
- mm->free_area_cache = base;
-
- /* requesting a specific address */
- if (addr) {
- addr = PAGE_ALIGN(addr);
- vma = find_vma(mm, addr);
- if (TASK_SIZE - len >= addr &&
- (!vma || addr + len <= vma->vm_start)
- && !is_hugepage_only_range(mm, addr,len))
- return addr;
- }
-
- if (len <= largest_hole) {
- largest_hole = 0;
- mm->free_area_cache = base;
- }
-try_again:
- /* make sure it can fit in the remaining address space */
- if (mm->free_area_cache < len)
- goto fail;
-
- /* either no address requested or cant fit in requested address hole */
- addr = (mm->free_area_cache - len) & PAGE_MASK;
- do {
-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(mm, addr, len)) {
- addr = (addr & ((~0UL) << HTLB_AREA_SHIFT)) - len;
- goto hugepage_recheck;
- }
-
- /*
- * Lookup failure means no vma is above this address,
- * i.e. return with success:
- */
- if (!(vma = find_vma_prev(mm, addr, &prev_vma)))
- return addr;
-
- /*
- * new region fits between prev_vma->vm_end and
- * vma->vm_start, use it:
- */
- if (addr+len <= vma->vm_start &&
- (!prev_vma || (addr >= prev_vma->vm_end))) {
- /* remember the address as a hint for next time */
- mm->cached_hole_size = largest_hole;
- return (mm->free_area_cache = addr);
- } else {
- /* pull free_area_cache down to the first hole */
- if (mm->free_area_cache == vma->vm_end) {
- mm->free_area_cache = vma->vm_start;
- mm->cached_hole_size = largest_hole;
- }
- }
-
- /* remember the largest hole we saw so far */
- if (addr + largest_hole < vma->vm_start)
- largest_hole = vma->vm_start - addr;
-
- /* try just below the current vma->vm_start */
- addr = vma->vm_start-len;
- } while (len <= vma->vm_start);
-
-fail:
- /*
- * if hint left us with no space for the requested
- * mapping then try again:
- */
- if (first_time) {
- mm->free_area_cache = base;
- largest_hole = 0;
- first_time = 0;
- goto try_again;
- }
- /*
- * A failed mmap() very likely causes application failure,
- * so fall back to the bottom-up function here. This scenario
- * can happen with large stack limits and large mmap()
- * allocations.
- */
- mm->free_area_cache = TASK_UNMAPPED_BASE;
- mm->cached_hole_size = ~0UL;
- addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
- /*
- * Restore the topdown base:
- */
- mm->free_area_cache = base;
- mm->cached_hole_size = ~0UL;
-
- return addr;
-}
-
-static int htlb_check_hinted_area(unsigned long addr, unsigned long len)
-{
- struct vm_area_struct *vma;
-
- vma = find_vma(current->mm, addr);
- if (TASK_SIZE - len >= addr &&
- (!vma || ((addr + len) <= vma->vm_start)))
- return 0;
-
- return -ENOMEM;
-}
-
-static unsigned long htlb_get_low_area(unsigned long len, u16 segmask)
-{
- unsigned long addr = 0;
- struct vm_area_struct *vma;
-
- vma = find_vma(current->mm, addr);
- while (addr + len <= 0x100000000UL) {
- BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
-
- if (! __within_hugepage_low_range(addr, len, segmask)) {
- addr = ALIGN(addr+1, 1<<SID_SHIFT);
- vma = find_vma(current->mm, addr);
- continue;
- }
-
- if (!vma || (addr + len) <= vma->vm_start)
- return addr;
- addr = ALIGN(vma->vm_end, HPAGE_SIZE);
- /* 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;
-}
-
-static unsigned long htlb_get_high_area(unsigned long len, u16 areamask)
-{
- unsigned long addr = 0x100000000UL;
- struct vm_area_struct *vma;
-
- vma = find_vma(current->mm, addr);
- while (addr + len <= TASK_SIZE_USER64) {
- BUG_ON(vma && (addr >= vma->vm_end)); /* invariant */
-
- 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);
- /* 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;
-}
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 (HPAGE_SHIFT == 0)
- return -EINVAL;
- if (len & ~HPAGE_MASK)
- return -EINVAL;
- if (len > TASK_SIZE)
- return -ENOMEM;
-
- if (!cpu_has_feature(CPU_FTR_16M_PAGE))
- return -EINVAL;
-
- /* Paranoia, caller should have dealt with this */
- BUG_ON((addr + len) < addr);
-
- /* Handle MAP_FIXED */
- if (flags & MAP_FIXED) {
- if (prepare_hugepage_range(addr, len, pgoff))
- return -EINVAL;
- return addr;
- }
-
- if (test_thread_flag(TIF_32BIT)) {
- curareas = current->mm->context.low_htlb_areas;
-
- /* First see if we can use the hint address */
- if (addr && (htlb_check_hinted_area(addr, len) == 0)) {
- areamask = LOW_ESID_MASK(addr, len);
- if (open_low_hpage_areas(current->mm, areamask) == 0)
- return addr;
- }
-
- /* Next see if we can map in the existing low areas */
- addr = htlb_get_low_area(len, curareas);
- if (addr != -ENOMEM)
- return addr;
-
- /* Finally go looking for areas to open */
- lastshift = 0;
- for (areamask = LOW_ESID_MASK(0x100000000UL-len, len);
- ! lastshift; areamask >>=1) {
- if (areamask & 1)
- lastshift = 1;
-
- addr = htlb_get_low_area(len, curareas | areamask);
- if ((addr != -ENOMEM)
- && open_low_hpage_areas(current->mm, areamask) == 0)
- return addr;
- }
- } else {
- curareas = current->mm->context.high_htlb_areas;
-
- /* First see if we can use the hint address */
- /* We discourage 64-bit processes from doing hugepage
- * mappings below 4GB (must use MAP_FIXED) */
- if ((addr >= 0x100000000UL)
- && (htlb_check_hinted_area(addr, len) == 0)) {
- areamask = HTLB_AREA_MASK(addr, len);
- if (open_high_hpage_areas(current->mm, areamask) == 0)
- return addr;
- }
-
- /* Next see if we can map in the existing high areas */
- addr = htlb_get_high_area(len, curareas);
- if (addr != -ENOMEM)
- return addr;
-
- /* Finally go looking for areas to open */
- 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;
+ return slice_get_unmapped_area(addr, len, flags,
+ mmu_huge_psize, 1, 0);
}
/*
Index: linux-cell/arch/powerpc/mm/mmu_context_64.c
===================================================================
--- linux-cell.orig/arch/powerpc/mm/mmu_context_64.c 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/mm/mmu_context_64.c 2007-05-08 15:27:52.000000000 +1000
@@ -28,6 +28,7 @@ int init_new_context(struct task_struct
{
int index;
int err;
+ int new_context = (mm->context.id == 0);
again:
if (!idr_pre_get(&mmu_context_idr, GFP_KERNEL))
@@ -50,9 +51,18 @@ again:
}
mm->context.id = index;
+#ifdef CONFIG_PPC_MM_SLICES
+ /* The old code would re-promote on fork, we don't do that
+ * when using slices as it could cause problem promoting slices
+ * that have been forced down to 4K
+ */
+ if (new_context)
+ slice_set_user_psize(mm, mmu_virtual_psize);
+#else
mm->context.user_psize = mmu_virtual_psize;
mm->context.sllp = SLB_VSID_USER |
mmu_psize_defs[mmu_virtual_psize].sllp;
+#endif
return 0;
}
Index: linux-cell/arch/powerpc/mm/slb_low.S
===================================================================
--- linux-cell.orig/arch/powerpc/mm/slb_low.S 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/mm/slb_low.S 2007-05-08 15:27:52.000000000 +1000
@@ -82,31 +82,45 @@ _GLOBAL(slb_miss_kernel_load_io)
srdi. r9,r10,USER_ESID_BITS
bne- 8f /* invalid ea bits set */
- /* Figure out if the segment contains huge pages */
-#ifdef CONFIG_HUGETLB_PAGE
-BEGIN_FTR_SECTION
- b 1f
-END_FTR_SECTION_IFCLR(CPU_FTR_16M_PAGE)
+
+ /* when using slices, we extract the psize off the slice bitmaps
+ * and then we need to get the sllp encoding off the mmu_psize_defs
+ * array.
+ *
+ * XXX This is a bit inefficient especially for the normal case,
+ * so we should try to implement a fast path for the standard page
+ * size using the old sllp value so we avoid the array. We cannot
+ * really do dynamic patching unfortunately as processes might flip
+ * between 4k and 64k standard page size
+ */
+#ifdef CONFIG_PPC_MM_SLICES
cmpldi r10,16
- lhz r9,PACALOWHTLBAREAS(r13)
- mr r11,r10
+ /* Get the slice index * 4 in r11 and matching slice size mask in r9 */
+ ld r9,PACALOWSLICESPSIZE(r13)
+ sldi r11,r10,2
blt 5f
+ ld r9,PACAHIGHSLICEPSIZE(r13)
+ srdi r11,r10,(SLICE_HIGH_SHIFT - SLICE_LOW_SHIFT - 2)
+ andi. r11,r11,0x3c
+
+5: /* Extract the psize and multiply to get an array offset */
+ srd r9,r9,r11
+ andi. r9,r9,0xf
+ mulli r9,r9,MMUPSIZEDEFSIZE
- lhz r9,PACAHIGHHTLBAREAS(r13)
- srdi r11,r10,(HTLB_AREA_SHIFT-SID_SHIFT)
-
-5: srd r9,r9,r11
- andi. r9,r9,1
- beq 1f
-_GLOBAL(slb_miss_user_load_huge)
- li r11,0
- b 2f
-1:
-#endif /* CONFIG_HUGETLB_PAGE */
-
+ /* Now get to the array and obtain the sllp
+ */
+ ld r11,PACATOC(r13)
+ ld r11,mmu_psize_defs@got(r11)
+ add r11,r11,r9
+ ld r11,MMUPSIZESLLP(r11)
+ ori r11,r11,SLB_VSID_USER
+#else
+ /* paca context sllp already contains the SLB_VSID_USER bits */
lhz r11,PACACONTEXTSLLP(r13)
-2:
+#endif /* CONFIG_PPC_MM_SLICES */
+
ld r9,PACACONTEXTID(r13)
rldimi r10,r9,USER_ESID_BITS,0
b slb_finish_load
Index: linux-cell/arch/powerpc/mm/hash_utils_64.c
===================================================================
--- linux-cell.orig/arch/powerpc/mm/hash_utils_64.c 2007-05-08 15:27:29.000000000 +1000
+++ linux-cell/arch/powerpc/mm/hash_utils_64.c 2007-05-08 15:28:34.000000000 +1000
@@ -51,6 +51,7 @@
#include <asm/cputable.h>
#include <asm/abs_addr.h>
#include <asm/sections.h>
+#include <asm/spu.h>
#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
@@ -601,8 +602,13 @@ static void demote_segment_4k(struct mm_
{
if (mm->context.user_psize == MMU_PAGE_4K)
return;
+#ifdef CONFIG_PPC_MM_SLICES
+ slice_set_user_psize(mm, MMU_PAGE_4K);
+#else /* CONFIG_PPC_MM_SLICES */
mm->context.user_psize = MMU_PAGE_4K;
mm->context.sllp = SLB_VSID_USER | mmu_psize_defs[MMU_PAGE_4K].sllp;
+#endif /* CONFIG_PPC_MM_SLICES */
+
#ifdef CONFIG_SPE_BASE
spu_flush_all_slbs(mm);
#endif
@@ -670,11 +676,14 @@ int hash_page(unsigned long ea, unsigned
if (user_region && cpus_equal(mm->cpu_vm_mask, tmp))
local = 1;
+#ifdef CONFIG_HUGETLB_PAGE
/* Handle hugepage regions */
- if (unlikely(in_hugepage_area(mm->context, ea))) {
+ if (HPAGE_SHIFT &&
+ unlikely(get_slice_psize(mm, ea) == mmu_huge_psize)) {
DBG_LOW(" -> huge page !\n");
return hash_huge_page(mm, access, ea, vsid, local, trap);
}
+#endif /* CONFIG_HUGETLB_PAGE */
/* Get PTE and page size from page tables */
ptep = find_linux_pte(pgdir, ea);
@@ -770,10 +779,13 @@ void hash_preload(struct mm_struct *mm,
unsigned long flags;
int local = 0;
- /* We don't want huge pages prefaulted for now
- */
- if (unlikely(in_hugepage_area(mm->context, ea)))
+ BUG_ON(REGION_ID(ea) != USER_REGION_ID);
+
+#ifdef CONFIG_PPC_MM_SLICES
+ /* We only prefault standard pages for now */
+ if (unlikely(get_slice_psize(mm, ea) != mm->context.user_psize));
return;
+#endif
DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx,"
" trap=%lx\n", mm, mm->pgd, ea, access, trap);
Index: linux-cell/arch/powerpc/mm/slb.c
===================================================================
--- linux-cell.orig/arch/powerpc/mm/slb.c 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/mm/slb.c 2007-05-08 15:27:52.000000000 +1000
@@ -198,12 +198,6 @@ void slb_initialize(void)
static int slb_encoding_inited;
extern unsigned int *slb_miss_kernel_load_linear;
extern unsigned int *slb_miss_kernel_load_io;
-#ifdef CONFIG_HUGETLB_PAGE
- extern unsigned int *slb_miss_user_load_huge;
- unsigned long huge_llp;
-
- huge_llp = mmu_psize_defs[mmu_huge_psize].sllp;
-#endif
/* Prepare our SLB miss handler based on our page size */
linear_llp = mmu_psize_defs[mmu_linear_psize].sllp;
@@ -220,11 +214,6 @@ void slb_initialize(void)
DBG("SLB: linear LLP = %04x\n", linear_llp);
DBG("SLB: io LLP = %04x\n", io_llp);
-#ifdef CONFIG_HUGETLB_PAGE
- patch_slb_encoding(slb_miss_user_load_huge,
- SLB_VSID_USER | huge_llp);
- DBG("SLB: huge LLP = %04x\n", huge_llp);
-#endif
}
get_paca()->stab_rr = SLB_NUM_BOLTED;
Index: linux-cell/arch/powerpc/platforms/cell/spu_base.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spu_base.c 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/spu_base.c 2007-05-08 15:27:52.000000000 +1000
@@ -144,12 +144,11 @@ static int __spu_trap_data_seg(struct sp
switch(REGION_ID(ea)) {
case USER_REGION_ID:
-#ifdef CONFIG_HUGETLB_PAGE
- if (in_hugepage_area(mm->context, ea))
- psize = mmu_huge_psize;
- else
+#ifdef CONFIG_PPC_MM_SLICES
+ psize = get_slice_psize(mm, ea);
+#else
+ psize = mm->context.user_psize;
#endif
- psize = mm->context.user_psize;
vsid = (get_vsid(mm->context.id, ea) << SLB_VSID_SHIFT) |
SLB_VSID_USER;
break;
Index: linux-cell/include/asm-powerpc/mmu-hash64.h
===================================================================
--- linux-cell.orig/include/asm-powerpc/mmu-hash64.h 2007-05-08 15:27:05.000000000 +1000
+++ linux-cell/include/asm-powerpc/mmu-hash64.h 2007-05-08 15:27:52.000000000 +1000
@@ -350,10 +350,13 @@ typedef unsigned long mm_context_id_t;
typedef struct {
mm_context_id_t id;
- u16 user_psize; /* page size index */
- u16 sllp; /* SLB entry page size encoding */
-#ifdef CONFIG_HUGETLB_PAGE
- u16 low_htlb_areas, high_htlb_areas;
+ u16 user_psize; /* page size index */
+
+#ifdef CONFIG_PPC_MM_SLICES
+ u64 low_slices_psize; /* SLB page size encodings */
+ u64 high_slices_psize; /* 4 bits per slice for now */
+#else
+ u16 sllp; /* SLB page size encoding */
#endif
unsigned long vdso_base;
} mm_context_t;
^ permalink raw reply [flat|nested] 9+ messages in thread* [PATCH 4/5] powerpc: spufs support for 64K LS mappings on 4K kernels
2007-05-08 6:27 [PATCH 0/5] This is my pending series for 2.6.22 Benjamin Herrenschmidt
` (2 preceding siblings ...)
2007-05-08 6:27 ` [PATCH 3/5] powerpc: Add ability to 4K kernel to hash in 64K pages Benjamin Herrenschmidt
@ 2007-05-08 6:27 ` Benjamin Herrenschmidt
2007-05-08 6:27 ` [PATCH 5/5] powerpc: Don't use SLAB/SLUB for PTE pages Benjamin Herrenschmidt
4 siblings, 0 replies; 9+ messages in thread
From: Benjamin Herrenschmidt @ 2007-05-08 6:27 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Hugh Dickins, Paul Mackerras
This patch adds an option to spufs when the kernel is configured for
4K page to give it the ability to use 64K pages for SPE local store
mappings.
Currently, we are optimistic and try order 4 allocations when creting
contexts. If that fails, the code will fallback to 4K automatically.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/platforms/cell/Kconfig | 15 +
arch/powerpc/platforms/cell/spufs/Makefile | 2
arch/powerpc/platforms/cell/spufs/context.c | 4
arch/powerpc/platforms/cell/spufs/file.c | 78 ++++++++--
arch/powerpc/platforms/cell/spufs/lscsa_alloc.c | 181 ++++++++++++++++++++++++
arch/powerpc/platforms/cell/spufs/switch.c | 28 +--
include/asm-powerpc/spu_csa.h | 10 +
7 files changed, 282 insertions(+), 36 deletions(-)
Index: linux-cell/arch/powerpc/platforms/cell/Kconfig
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/Kconfig 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/Kconfig 2007-05-08 15:29:26.000000000 +1000
@@ -35,6 +35,21 @@ config SPU_FS
Units on machines implementing the Broadband Processor
Architecture.
+config SPU_FS_64K_LS
+ bool "Use 64K pages to map SPE local store"
+ # we depend on PPC_MM_SLICES for now rather than selecting
+ # it because we depend on hugetlbfs hooks being present. We
+ # will fix that when the generic code has been improved to
+ # not require hijacking hugetlbfs hooks.
+ depends on SPU_FS && PPC_MM_SLICES && !PPC_64K_PAGES
+ default y
+ select PPC_HAS_HASH_64K
+ help
+ This option causes SPE local stores to be mapped in process
+ address spaces using 64K pages while the rest of the kernel
+ uses 4K pages. This can improve performances of applications
+ using multiple SPEs by lowering the TLB pressure on them.
+
config SPU_BASE
bool
default n
Index: linux-cell/arch/powerpc/platforms/cell/spufs/context.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/context.c 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/spufs/context.c 2007-05-08 15:29:26.000000000 +1000
@@ -36,10 +36,8 @@ struct spu_context *alloc_spu_context(st
/* Binding to physical processor deferred
* until spu_activate().
*/
- spu_init_csa(&ctx->csa);
- if (!ctx->csa.lscsa) {
+ if (spu_init_csa(&ctx->csa))
goto out_free;
- }
spin_lock_init(&ctx->mmio_lock);
spin_lock_init(&ctx->mapping_lock);
kref_init(&ctx->kref);
Index: linux-cell/arch/powerpc/platforms/cell/spufs/switch.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/switch.c 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/spufs/switch.c 2007-05-08 15:29:26.000000000 +1000
@@ -2189,40 +2189,30 @@ static void init_priv2(struct spu_state
* as it is by far the largest of the context save regions,
* and may need to be pinned or otherwise specially aligned.
*/
-void spu_init_csa(struct spu_state *csa)
+int spu_init_csa(struct spu_state *csa)
{
- struct spu_lscsa *lscsa;
- unsigned char *p;
+ int rc;
if (!csa)
- return;
+ return -EINVAL;
memset(csa, 0, sizeof(struct spu_state));
- lscsa = vmalloc(sizeof(struct spu_lscsa));
- if (!lscsa)
- return;
+ rc = spu_alloc_lscsa(csa);
+ if (rc)
+ return rc;
- memset(lscsa, 0, sizeof(struct spu_lscsa));
- csa->lscsa = lscsa;
spin_lock_init(&csa->register_lock);
- /* Set LS pages reserved to allow for user-space mapping. */
- for (p = lscsa->ls; p < lscsa->ls + LS_SIZE; p += PAGE_SIZE)
- SetPageReserved(vmalloc_to_page(p));
-
init_prob(csa);
init_priv1(csa);
init_priv2(csa);
+
+ return 0;
}
EXPORT_SYMBOL_GPL(spu_init_csa);
void spu_fini_csa(struct spu_state *csa)
{
- /* Clear reserved bit before vfree. */
- unsigned char *p;
- for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE)
- ClearPageReserved(vmalloc_to_page(p));
-
- vfree(csa->lscsa);
+ spu_free_lscsa(csa);
}
EXPORT_SYMBOL_GPL(spu_fini_csa);
Index: linux-cell/include/asm-powerpc/spu_csa.h
===================================================================
--- linux-cell.orig/include/asm-powerpc/spu_csa.h 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/include/asm-powerpc/spu_csa.h 2007-05-08 15:29:26.000000000 +1000
@@ -235,6 +235,12 @@ struct spu_priv2_collapsed {
*/
struct spu_state {
struct spu_lscsa *lscsa;
+#ifdef CONFIG_SPU_FS_64K_LS
+ int use_big_pages;
+ /* One struct page per 64k page */
+#define SPU_LSCSA_NUM_BIG_PAGES (sizeof(struct spu_lscsa) / 0x10000)
+ struct page *lscsa_pages[SPU_LSCSA_NUM_BIG_PAGES];
+#endif
struct spu_problem_collapsed prob;
struct spu_priv1_collapsed priv1;
struct spu_priv2_collapsed priv2;
@@ -247,12 +253,14 @@ struct spu_state {
spinlock_t register_lock;
};
-extern void spu_init_csa(struct spu_state *csa);
+extern int spu_init_csa(struct spu_state *csa);
extern void spu_fini_csa(struct spu_state *csa);
extern int spu_save(struct spu_state *prev, struct spu *spu);
extern int spu_restore(struct spu_state *new, struct spu *spu);
extern int spu_switch(struct spu_state *prev, struct spu_state *new,
struct spu *spu);
+extern int spu_alloc_lscsa(struct spu_state *csa);
+extern void spu_free_lscsa(struct spu_state *csa);
#endif /* !__SPU__ */
#endif /* __KERNEL__ */
Index: linux-cell/arch/powerpc/platforms/cell/spufs/Makefile
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/Makefile 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/spufs/Makefile 2007-05-08 15:29:26.000000000 +1000
@@ -1,4 +1,4 @@
-obj-y += switch.o fault.o
+obj-y += switch.o fault.o lscsa_alloc.o
obj-$(CONFIG_SPU_FS) += spufs.o
spufs-y += inode.o file.o context.o syscalls.o coredump.o
Index: linux-cell/arch/powerpc/platforms/cell/spufs/lscsa_alloc.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-cell/arch/powerpc/platforms/cell/spufs/lscsa_alloc.c 2007-05-08 15:29:26.000000000 +1000
@@ -0,0 +1,181 @@
+/*
+ * SPU local store allocation routines
+ *
+ * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+
+#include <asm/spu.h>
+#include <asm/spu_csa.h>
+#include <asm/mmu.h>
+
+static int spu_alloc_lscsa_std(struct spu_state *csa)
+{
+ struct spu_lscsa *lscsa;
+ unsigned char *p;
+
+ lscsa = vmalloc(sizeof(struct spu_lscsa));
+ if (!lscsa)
+ return -ENOMEM;
+ memset(lscsa, 0, sizeof(struct spu_lscsa));
+ csa->lscsa = lscsa;
+
+ /* Set LS pages reserved to allow for user-space mapping. */
+ for (p = lscsa->ls; p < lscsa->ls + LS_SIZE; p += PAGE_SIZE)
+ SetPageReserved(vmalloc_to_page(p));
+
+ return 0;
+}
+
+static void spu_free_lscsa_std(struct spu_state *csa)
+{
+ /* Clear reserved bit before vfree. */
+ unsigned char *p;
+
+ if (csa->lscsa == NULL)
+ return;
+
+ for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE)
+ ClearPageReserved(vmalloc_to_page(p));
+
+ vfree(csa->lscsa);
+}
+
+#ifdef CONFIG_SPU_FS_64K_LS
+
+#define SPU_64K_PAGE_SHIFT 16
+#define SPU_64K_PAGE_ORDER (SPU_64K_PAGE_SHIFT - PAGE_SHIFT)
+#define SPU_64K_PAGE_COUNT (1ul << SPU_64K_PAGE_ORDER)
+
+int spu_alloc_lscsa(struct spu_state *csa)
+{
+ struct page **pgarray;
+ unsigned char *p;
+ int i, j, n_4k;
+
+ /* Check availability of 64K pages */
+ if (mmu_psize_defs[MMU_PAGE_64K].shift == 0)
+ goto fail;
+
+ csa->use_big_pages = 1;
+
+ pr_debug("spu_alloc_lscsa(csa=0x%p), trying to allocate 64K pages\n",
+ csa);
+
+ /* First try to allocate our 64K pages. We need 5 of them
+ * with the current implementation. In the future, we should try
+ * to separate the lscsa with the actual local store image, thus
+ * allowing us to require only 4 64K pages per context
+ */
+ for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++) {
+ /* XXX This is likely to fail, we should use a special pool
+ * similiar to what hugetlbfs does.
+ */
+ csa->lscsa_pages[i] = alloc_pages(GFP_KERNEL,
+ SPU_64K_PAGE_ORDER);
+ if (csa->lscsa_pages[i] == NULL)
+ goto fail;
+ }
+
+ pr_debug(" success ! creating vmap...\n");
+
+ /* Now we need to create a vmalloc mapping of these for the kernel
+ * and SPU context switch code to use. Currently, we stick to a
+ * normal kernel vmalloc mapping, which in our case will be 4K
+ */
+ n_4k = SPU_64K_PAGE_COUNT * SPU_LSCSA_NUM_BIG_PAGES;
+ pgarray = kmalloc(sizeof(struct page *) * n_4k, GFP_KERNEL);
+ if (pgarray == NULL)
+ goto fail;
+ for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++)
+ for (j = 0; j < SPU_64K_PAGE_COUNT; j++)
+ /* We assume all the struct page's are contiguous
+ * which should be hopefully the case for an order 4
+ * allocation..
+ */
+ pgarray[i * SPU_64K_PAGE_COUNT + j] =
+ csa->lscsa_pages[i] + j;
+ csa->lscsa = vmap(pgarray, n_4k, VM_USERMAP, PAGE_KERNEL);
+ kfree(pgarray);
+ if (csa->lscsa == NULL)
+ goto fail;
+
+ memset(csa->lscsa, 0, sizeof(struct spu_lscsa));
+
+ /* Set LS pages reserved to allow for user-space mapping.
+ *
+ * XXX isn't that a bit obsolete ? I think we should just
+ * make sure the page count is high enough. Anyway, won't harm
+ * for now
+ */
+ for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE)
+ SetPageReserved(vmalloc_to_page(p));
+
+ pr_debug(" all good !\n");
+
+ return 0;
+fail:
+ pr_debug("spufs: failed to allocate lscsa 64K pages, falling back\n");
+ spu_free_lscsa(csa);
+ return spu_alloc_lscsa_std(csa);
+}
+
+void spu_free_lscsa(struct spu_state *csa)
+{
+ unsigned char *p;
+ int i;
+
+ if (!csa->use_big_pages) {
+ spu_free_lscsa_std(csa);
+ return;
+ }
+ csa->use_big_pages = 0;
+
+ if (csa->lscsa == NULL)
+ goto free_pages;
+
+ for (p = csa->lscsa->ls; p < csa->lscsa->ls + LS_SIZE; p += PAGE_SIZE)
+ ClearPageReserved(vmalloc_to_page(p));
+
+ vunmap(csa->lscsa);
+ csa->lscsa = NULL;
+
+ free_pages:
+
+ for (i = 0; i < SPU_LSCSA_NUM_BIG_PAGES; i++)
+ if (csa->lscsa_pages[i])
+ __free_pages(csa->lscsa_pages[i], SPU_64K_PAGE_ORDER);
+}
+
+#else /* CONFIG_SPU_FS_64K_LS */
+
+int spu_alloc_lscsa(struct spu_state *csa)
+{
+ return spu_alloc_lscsa_std(csa);
+}
+
+void spu_free_lscsa(struct spu_state *csa)
+{
+ spu_free_lscsa_std(csa);
+}
+
+#endif /* !defined(CONFIG_SPU_FS_64K_LS) */
Index: linux-cell/arch/powerpc/platforms/cell/spufs/file.c
===================================================================
--- linux-cell.orig/arch/powerpc/platforms/cell/spufs/file.c 2007-05-08 15:27:02.000000000 +1000
+++ linux-cell/arch/powerpc/platforms/cell/spufs/file.c 2007-05-08 15:29:26.000000000 +1000
@@ -118,14 +118,32 @@ spufs_mem_write(struct file *file, const
static unsigned long spufs_mem_mmap_nopfn(struct vm_area_struct *vma,
unsigned long address)
{
- struct spu_context *ctx = vma->vm_file->private_data;
- unsigned long pfn, offset = address - vma->vm_start;
-
- offset += vma->vm_pgoff << PAGE_SHIFT;
+ struct spu_context *ctx = vma->vm_file->private_data;
+ unsigned long pfn, offset, addr0 = address;
+#ifdef CONFIG_SPU_FS_64K_LS
+ struct spu_state *csa = &ctx->csa;
+ int psize;
+
+ /* Check what page size we are using */
+ psize = get_slice_psize(vma->vm_mm, address);
+
+ /* Some sanity checking */
+ BUG_ON(csa->use_big_pages != (psize == MMU_PAGE_64K));
+
+ /* Wow, 64K, cool, we need to align the address though */
+ if (csa->use_big_pages) {
+ BUG_ON(vma->vm_start & 0xffff);
+ address &= ~0xfffful;
+ }
+#endif /* CONFIG_SPU_FS_64K_LS */
+ offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
if (offset >= LS_SIZE)
return NOPFN_SIGBUS;
+ pr_debug("spufs_mem_mmap_nopfn address=0x%lx -> 0x%lx, offset=0x%lx\n",
+ addr0, address, offset);
+
spu_acquire(ctx);
if (ctx->state == SPU_STATE_SAVED) {
@@ -149,9 +167,24 @@ static struct vm_operations_struct spufs
.nopfn = spufs_mem_mmap_nopfn,
};
-static int
-spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)
+static int spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)
{
+#ifdef CONFIG_SPU_FS_64K_LS
+ struct spu_context *ctx = file->private_data;
+ struct spu_state *csa = &ctx->csa;
+
+ /* Sanity check VMA alignment */
+ if (csa->use_big_pages) {
+ pr_debug("spufs_mem_mmap 64K, start=0x%lx, end=0x%lx,"
+ " pgoff=0x%lx\n", vma->vm_start, vma->vm_end,
+ vma->vm_pgoff);
+ if (vma->vm_start & 0xffff)
+ return -EINVAL;
+ if (vma->vm_pgoff & 0xf)
+ return -EINVAL;
+ }
+#endif /* CONFIG_SPU_FS_64K_LS */
+
if (!(vma->vm_flags & VM_SHARED))
return -EINVAL;
@@ -163,13 +196,34 @@ spufs_mem_mmap(struct file *file, struct
return 0;
}
+#ifdef CONFIG_SPU_FS_64K_LS
+unsigned long spufs_get_unmapped_area(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct spu_context *ctx = file->private_data;
+ struct spu_state *csa = &ctx->csa;
+
+ /* If not using big pages, fallback to normal MM g_u_a */
+ if (!csa->use_big_pages)
+ return current->mm->get_unmapped_area(file, addr, len,
+ pgoff, flags);
+
+ /* Else, try to obtain a 64K pages slice */
+ return slice_get_unmapped_area(addr, len, flags,
+ MMU_PAGE_64K, 1, 0);
+}
+#endif /* CONFIG_SPU_FS_64K_LS */
+
static const struct file_operations spufs_mem_fops = {
- .open = spufs_mem_open,
- .release = spufs_mem_release,
- .read = spufs_mem_read,
- .write = spufs_mem_write,
- .llseek = generic_file_llseek,
- .mmap = spufs_mem_mmap,
+ .open = spufs_mem_open,
+ .read = spufs_mem_read,
+ .write = spufs_mem_write,
+ .llseek = generic_file_llseek,
+ .mmap = spufs_mem_mmap,
+#ifdef CONFIG_SPU_FS_64K_LS
+ .get_unmapped_area = spufs_get_unmapped_area,
+#endif
};
static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
^ permalink raw reply [flat|nested] 9+ messages in thread