9 files changed, 530 insertions, 0 deletions

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 3ad2c4af099c..295b5abee72f 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -50,6 +50,10 @@ config SCHED_NO_NO_OMIT_FRAME_POINTER
         bool
         default y
 
+config IA64_UNCACHED_ALLOCATOR
+        bool
+        select GENERIC_ALLOCATOR
+
 choice
         prompt "System type"
         default IA64_GENERIC
diff --git a/arch/ia64/kernel/Makefile b/arch/ia64/kernel/Makefile
index c1a02bbc252c..4c73d8ba2e3d 100644
--- a/arch/ia64/kernel/Makefile
+++ b/arch/ia64/kernel/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_SMP)		+= smp.o smpboot.o domain.o
 obj-$(CONFIG_PERFMON)           += perfmon_default_smpl.o
 obj-$(CONFIG_IA64_CYCLONE)      += cyclone.o
 obj-$(CONFIG_IA64_MCA_RECOVERY) += mca_recovery.o
+obj-$(CONFIG_IA64_UNCACHED_ALLOCATOR)   += uncached.o
 mca_recovery-y                  += mca_drv.o mca_drv_asm.o
 
 # The gate DSO image is built using a special linker script.
diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c
index 4a3b1aac43e7..179f230816ed 100644
--- a/arch/ia64/kernel/efi.c
+++ b/arch/ia64/kernel/efi.c
@@ -410,6 +410,38 @@ efi_memmap_walk (efi_freemem_callback_t callback, void *arg)
 }
 
 /*
+ * Walk the EFI memory map to pull out leftover pages in the lower
+ * memory regions which do not end up in the regular memory map and
+ * stick them into the uncached allocator
+ *
+ * The regular walk function is significantly more complex than the
+ * uncached walk which means it really doesn't make sense to try and
+ * marge the two.
+ */
+void __init
+efi_memmap_walk_uc (efi_freemem_callback_t callback)
+{
+        void *efi_map_start, *efi_map_end, *p;
+        efi_memory_desc_t *md;
+        u64 efi_desc_size, start, end;
+
+        efi_map_start = __va(ia64_boot_param->efi_memmap);
+        efi_map_end = efi_map_start + ia64_boot_param->efi_memmap_size;
+        efi_desc_size = ia64_boot_param->efi_memdesc_size;
+
+        for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
+                md = p;
+                if (md->attribute == EFI_MEMORY_UC) {
+                        start = PAGE_ALIGN(md->phys_addr);
+                        end = PAGE_ALIGN((md->phys_addr+(md->num_pages << EFI_PAGE_SHIFT)) & PAGE_MASK);
+                        if ((*callback)(start, end, NULL) < 0)
+                                return;
+                }
+        }
+}
+
+
+/*
  * Look for the PAL_CODE region reported by EFI and maps it using an
  * ITR to enable safe PAL calls in virtual mode.  See IA-64 Processor
  * Abstraction Layer chapter 11 in ADAG
diff --git a/arch/ia64/kernel/uncached.c b/arch/ia64/kernel/uncached.c
new file mode 100644
index 000000000000..490dfc9ab47f
--- /dev/null
+++ b/arch/ia64/kernel/uncached.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2001-2005 Silicon Graphics, Inc.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ * A simple uncached page allocator using the generic allocator. This
+ * allocator first utilizes the spare (spill) pages found in the EFI
+ * memmap and will then start converting cached pages to uncached ones
+ * at a granule at a time. Node awareness is implemented by having a
+ * pool of pages per node.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/efi.h>
+#include <linux/genalloc.h>
+#include <asm/page.h>
+#include <asm/pal.h>
+#include <asm/system.h>
+#include <asm/pgtable.h>
+#include <asm/atomic.h>
+#include <asm/tlbflush.h>
+#include <asm/sn/arch.h>
+
+#define DEBUG   0
+
+#if DEBUG
+#define dprintk                 printk
+#else
+#define dprintk(x...)           do { } while (0)
+#endif
+
+void __init efi_memmap_walk_uc (efi_freemem_callback_t callback);
+
+#define MAX_UNCACHED_GRANULES   5
+static int allocated_granules;
+
+struct gen_pool *uncached_pool[MAX_NUMNODES];
+
+
+static void uncached_ipi_visibility(void *data)
+{
+        int status;
+
+        status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
+        if ((status != PAL_VISIBILITY_OK) &&
+            (status != PAL_VISIBILITY_OK_REMOTE_NEEDED))
+                printk(KERN_DEBUG "pal_prefetch_visibility() returns %i on "
+                       "CPU %i\n", status, get_cpu());
+}
+
+
+static void uncached_ipi_mc_drain(void *data)
+{
+        int status;
+        status = ia64_pal_mc_drain();
+        if (status)
+                printk(KERN_WARNING "ia64_pal_mc_drain() failed with %i on "
+                       "CPU %i\n", status, get_cpu());
+}
+
+
+static unsigned long
+uncached_get_new_chunk(struct gen_pool *poolp)
+{
+        struct page *page;
+        void *tmp;
+        int status, i;
+        unsigned long addr, node;
+
+        if (allocated_granules >= MAX_UNCACHED_GRANULES)
+                return 0;
+
+        node = poolp->private;
+        page = alloc_pages_node(node, GFP_KERNEL | __GFP_ZERO,
+                                IA64_GRANULE_SHIFT-PAGE_SHIFT);
+
+        dprintk(KERN_INFO "get_new_chunk page %p, addr %lx\n",
+                page, (unsigned long)(page-vmem_map) << PAGE_SHIFT);
+
+        /*
+         * Do magic if no mem on local node! XXX
+         */
+        if (!page)
+                return 0;
+        tmp = page_address(page);
+
+        /*
+         * There's a small race here where it's possible for someone to
+         * access the page through /dev/mem halfway through the conversion
+         * to uncached - not sure it's really worth bothering about
+         */
+        for (i = 0; i < (IA64_GRANULE_SIZE / PAGE_SIZE); i++)
+                SetPageUncached(&page[i]);
+
+        flush_tlb_kernel_range(tmp, tmp + IA64_GRANULE_SIZE);
+
+        status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
+
+        dprintk(KERN_INFO "pal_prefetch_visibility() returns %i on cpu %i\n",
+                status, get_cpu());
+
+        if (!status) {
+                status = smp_call_function(uncached_ipi_visibility, NULL, 0, 1);
+                if (status)
+                        printk(KERN_WARNING "smp_call_function failed for "
+                               "uncached_ipi_visibility! (%i)\n", status);
+        }
+
+        if (ia64_platform_is("sn2"))
+                sn_flush_all_caches((unsigned long)tmp, IA64_GRANULE_SIZE);
+        else
+                flush_icache_range((unsigned long)tmp,
+                                   (unsigned long)tmp+IA64_GRANULE_SIZE);
+
+        ia64_pal_mc_drain();
+        status = smp_call_function(uncached_ipi_mc_drain, NULL, 0, 1);
+        if (status)
+                printk(KERN_WARNING "smp_call_function failed for "
+                       "uncached_ipi_mc_drain! (%i)\n", status);
+
+        addr = (unsigned long)tmp - PAGE_OFFSET + __IA64_UNCACHED_OFFSET;
+
+        allocated_granules++;
+        return addr;
+}
+
+
+/*
+ * uncached_alloc_page
+ *
+ * Allocate 1 uncached page. Allocates on the requested node. If no
+ * uncached pages are available on the requested node, roundrobin starting
+ * with higher nodes.
+ */
+unsigned long
+uncached_alloc_page(int nid)
+{
+        unsigned long maddr;
+
+        maddr = gen_pool_alloc(uncached_pool[nid], PAGE_SIZE);
+
+        dprintk(KERN_DEBUG "uncached_alloc_page returns %lx on node %i\n",
+                maddr, nid);
+
+        /*
+         * If no memory is availble on our local node, try the
+         * remaining nodes in the system.
+         */
+        if (!maddr) {
+                int i;
+
+                for (i = MAX_NUMNODES - 1; i >= 0; i--) {
+                        if (i == nid || !node_online(i))
+                                continue;
+                        maddr = gen_pool_alloc(uncached_pool[i], PAGE_SIZE);
+                        dprintk(KERN_DEBUG "uncached_alloc_page alternate search "
+                                "returns %lx on node %i\n", maddr, i);
+                        if (maddr) {
+                                break;
+                        }
+                }
+        }
+
+        return maddr;
+}
+EXPORT_SYMBOL(uncached_alloc_page);
+
+
+/*
+ * uncached_free_page
+ *
+ * Free a single uncached page.
+ */
+void
+uncached_free_page(unsigned long maddr)
+{
+        int node;
+
+        node = nasid_to_cnodeid(NASID_GET(maddr));
+
+        dprintk(KERN_DEBUG "uncached_free_page(%lx) on node %i\n", maddr, node);
+
+        if ((maddr & (0XFUL << 60)) != __IA64_UNCACHED_OFFSET)
+                panic("uncached_free_page invalid address %lx\n", maddr);
+
+        gen_pool_free(uncached_pool[node], maddr, PAGE_SIZE);
+}
+EXPORT_SYMBOL(uncached_free_page);
+
+
+/*
+ * uncached_build_memmap,
+ *
+ * Called at boot time to build a map of pages that can be used for
+ * memory special operations.
+ */
+static int __init
+uncached_build_memmap(unsigned long start, unsigned long end, void *arg)
+{
+        long length;
+        unsigned long vstart, vend;
+        int node;
+
+        length = end - start;
+        vstart = start + __IA64_UNCACHED_OFFSET;
+        vend = end + __IA64_UNCACHED_OFFSET;
+
+        dprintk(KERN_ERR "uncached_build_memmap(%lx %lx)\n", start, end);
+
+        memset((char *)vstart, 0, length);
+
+        node = nasid_to_cnodeid(NASID_GET(start));
+
+        for (; vstart < vend ; vstart += PAGE_SIZE) {
+                dprintk(KERN_INFO "sticking %lx into the pool!\n", vstart);
+                gen_pool_free(uncached_pool[node], vstart, PAGE_SIZE);
+        }
+
+        return 0;
+}
+
+
+static int __init uncached_init(void) {
+        int i;
+
+        for (i = 0; i < MAX_NUMNODES; i++) {
+                if (!node_online(i))
+                        continue;
+                uncached_pool[i] = gen_pool_create(0, IA64_GRANULE_SHIFT,
+                                                   &uncached_get_new_chunk, i);
+        }
+
+        efi_memmap_walk_uc(uncached_build_memmap);
+
+        return 0;
+}
+
+__initcall(uncached_init);
diff --git a/include/asm-ia64/uncached.h b/include/asm-ia64/uncached.h
new file mode 100644
index 000000000000..b82d923b73c1
--- /dev/null
+++ b/include/asm-ia64/uncached.h
@@ -0,0 +1,12 @@
+/*
+ * Copyright (C) 2001-2005 Silicon Graphics, Inc.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ * Prototypes for the uncached page allocator
+ */
+
+extern unsigned long uncached_alloc_page(int nid);
+extern void uncached_free_page(unsigned long);
diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
new file mode 100644
index 000000000000..7fd0576a4454
--- /dev/null
+++ b/include/linux/genalloc.h
@@ -0,0 +1,40 @@
+/*
+ * Basic general purpose allocator for managing special purpose memory
+ * not managed by the regular kmalloc/kfree interface.
+ * Uses for this includes on-device special memory, uncached memory
+ * etc.
+ *
+ * This code is based on the buddy allocator found in the sym53c8xx_2
+ * driver, adapted for general purpose use.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/spinlock.h>
+
+#define ALLOC_MIN_SHIFT         5 /* 32 bytes minimum */
+/*
+ *  Link between free memory chunks of a given size.
+ */
+struct gen_pool_link {
+        struct gen_pool_link *next;
+};
+
+/*
+ *  Memory pool descriptor.
+ */
+struct gen_pool {
+        spinlock_t lock;
+        unsigned long (*get_new_chunk)(struct gen_pool *);
+        struct gen_pool *next;
+        struct gen_pool_link *h;
+        unsigned long private;
+        int max_chunk_shift;
+};
+
+unsigned long gen_pool_alloc(struct gen_pool *poolp, int size);
+void gen_pool_free(struct gen_pool *mp, unsigned long ptr, int size);
+struct gen_pool *gen_pool_create(int nr_chunks, int max_chunk_shift,
+                                 unsigned long (*fp)(struct gen_pool *),
+                                 unsigned long data);
diff --git a/lib/Kconfig b/lib/Kconfig
index eeb45225248f..2d4d4e3bc4aa 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -40,6 +40,12 @@ config ZLIB_DEFLATE
         tristate
 
 #
+# Generic allocator support is selected if needed
+#
+config GENERIC_ALLOCATOR
+        boolean
+
+#
 # reed solomon support is select'ed if needed
 #
 config REED_SOLOMON
diff --git a/lib/Makefile b/lib/Makefile
index 5f10cb898407..dcb4231916e2 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_CRC_CCITT)	+= crc-ccitt.o
 obj-$(CONFIG_CRC32)     += crc32.o
 obj-$(CONFIG_LIBCRC32C) += libcrc32c.o
 obj-$(CONFIG_GENERIC_IOMAP) += iomap.o
+obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o
 
 obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/
 obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/
diff --git a/lib/genalloc.c b/lib/genalloc.c
new file mode 100644
index 000000000000..d6d30d2e7166
--- /dev/null
+++ b/lib/genalloc.c
@@ -0,0 +1,188 @@
+/*
+ * Basic general purpose allocator for managing special purpose memory
+ * not managed by the regular kmalloc/kfree interface.
+ * Uses for this includes on-device special memory, uncached memory
+ * etc.
+ *
+ * This code is based on the buddy allocator found in the sym53c8xx_2
+ * driver Copyright (C) 1999-2001  Gerard Roudier <groudier@free.fr>,
+ * and adapted for general purpose use.
+ *
+ * Copyright 2005 (C) Jes Sorensen <jes@trained-monkey.org>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/genalloc.h>
+
+#include <asm/page.h>
+
+
+struct gen_pool *gen_pool_create(int nr_chunks, int max_chunk_shift,
+                                 unsigned long (*fp)(struct gen_pool *),
+                                 unsigned long data)
+{
+        struct gen_pool *poolp;
+        unsigned long tmp;
+        int i;
+
+        /*
+         * This is really an arbitrary limit, +10 is enough for
+         * IA64_GRANULE_SHIFT, aka 16MB. If anyone needs a large limit
+         * this can be increased without problems.
+         */
+        if ((max_chunk_shift > (PAGE_SHIFT + 10)) ||
+            ((max_chunk_shift < ALLOC_MIN_SHIFT) && max_chunk_shift))
+                return NULL;
+
+        if (!max_chunk_shift)
+                max_chunk_shift = PAGE_SHIFT;
+
+        poolp = kmalloc(sizeof(struct gen_pool), GFP_KERNEL);
+        if (!poolp)
+                return NULL;
+        memset(poolp, 0, sizeof(struct gen_pool));
+        poolp->h = kmalloc(sizeof(struct gen_pool_link) *
+                           (max_chunk_shift - ALLOC_MIN_SHIFT + 1),
+                           GFP_KERNEL);
+        if (!poolp->h) {
+                printk(KERN_WARNING "gen_pool_alloc() failed to allocate\n");
+                kfree(poolp);
+                return NULL;
+        }
+        memset(poolp->h, 0, sizeof(struct gen_pool_link) *
+               (max_chunk_shift - ALLOC_MIN_SHIFT + 1));
+
+        spin_lock_init(&poolp->lock);
+        poolp->get_new_chunk = fp;
+        poolp->max_chunk_shift = max_chunk_shift;
+        poolp->private = data;
+
+        for (i = 0; i < nr_chunks; i++) {
+                tmp = poolp->get_new_chunk(poolp);
+                printk(KERN_INFO "allocated %lx\n", tmp);
+                if (!tmp)
+                        break;
+                gen_pool_free(poolp, tmp, (1 << poolp->max_chunk_shift));
+        }
+
+        return poolp;
+}
+EXPORT_SYMBOL(gen_pool_create);
+
+
+/*
+ *  Simple power of two buddy-like generic allocator.
+ *  Provides naturally aligned memory chunks.
+ */
+unsigned long gen_pool_alloc(struct gen_pool *poolp, int size)
+{
+        int j, i, s, max_chunk_size;
+        unsigned long a, flags;
+        struct gen_pool_link *h = poolp->h;
+
+        max_chunk_size = 1 << poolp->max_chunk_shift;
+
+        if (size > max_chunk_size)
+                return 0;
+
+        i = 0;
+
+        size = max(size, 1 << ALLOC_MIN_SHIFT);
+        s = roundup_pow_of_two(size);
+
+        j = i;
+
+        spin_lock_irqsave(&poolp->lock, flags);
+        while (!h[j].next) {
+                if (s == max_chunk_size) {
+                        struct gen_pool_link *ptr;
+                        spin_unlock_irqrestore(&poolp->lock, flags);
+                        ptr = (struct gen_pool_link *)poolp->get_new_chunk(poolp);
+                        spin_lock_irqsave(&poolp->lock, flags);
+                        h[j].next = ptr;
+                        if (h[j].next)
+                                h[j].next->next = NULL;
+                        break;
+                }
+                j++;
+                s <<= 1;
+        }
+        a = (unsigned long) h[j].next;
+        if (a) {
+                h[j].next = h[j].next->next;
+                /*
+                 * This should be split into a seperate function doing
+                 * the chunk split in order to support custom
+                 * handling memory not physically accessible by host
+                 */
+                while (j > i) {
+                        j -= 1;
+                        s >>= 1;
+                        h[j].next = (struct gen_pool_link *) (a + s);
+                        h[j].next->next = NULL;
+                }
+        }
+        spin_unlock_irqrestore(&poolp->lock, flags);
+        return a;
+}
+EXPORT_SYMBOL(gen_pool_alloc);
+
+
+/*
+ *  Counter-part of the generic allocator.
+ */
+void gen_pool_free(struct gen_pool *poolp, unsigned long ptr, int size)
+{
+        struct gen_pool_link *q;
+        struct gen_pool_link *h = poolp->h;
+        unsigned long a, b, flags;
+        int i, s, max_chunk_size;
+
+        max_chunk_size = 1 << poolp->max_chunk_shift;
+
+        if (size > max_chunk_size)
+                return;
+
+        i = 0;
+
+        size = max(size, 1 << ALLOC_MIN_SHIFT);
+        s = roundup_pow_of_two(size);
+
+        a = ptr;
+
+        spin_lock_irqsave(&poolp->lock, flags);
+        while (1) {
+                if (s == max_chunk_size) {
+                        ((struct gen_pool_link *)a)->next = h[i].next;
+                        h[i].next = (struct gen_pool_link *)a;
+                        break;
+                }
+                b = a ^ s;
+                q = &h[i];
+
+                while (q->next && q->next != (struct gen_pool_link *)b)
+                        q = q->next;
+
+                if (!q->next) {
+                        ((struct gen_pool_link *)a)->next = h[i].next;
+                        h[i].next = (struct gen_pool_link *)a;
+                        break;
+                }
+                q->next = q->next->next;
+                a = a & b;
+                s <<= 1;
+                i++;
+        }
+        spin_unlock_irqrestore(&poolp->lock, flags);
+}
+EXPORT_SYMBOL(gen_pool_free);