Re: [rfc] generic allocator and mspec driver

From: Jes Sorensen <jes_at_wildopensource.com>
Date: 2005-02-17 01:17:03
Hi

Here's another version of the mspec driver with the generic
allocator. I have tried to implement all the features we discussed on
the list earlier, including marking pages as uncached using PG_arch_1
and making /dev/mem honor it. In order to do so I had to move our
/dev/mem read/write functions into arch/ia64/kernel to avoid totally
cluttering drivers/char/mem.c with #ifdefs. I also moved  the mspec.c
driver to arch/ia64/kernel to reflect that it now works on non-sn
hardware for uncached and cached mappings.

Any more ideas/objections for this one?

The patch is still against 2.6.11-rc2-mm2 however it won't compile
straight out of the box as it depends on another patch I dumped on
Jesse which moved shubio.h to include/asm/sn

Cheers,
Jes

diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/Kconfig linux-2.6.11-rc2-mm2/arch/ia64/Kconfig
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/Kconfig	2005-02-02 04:31:21 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/Kconfig	2005-02-16 04:26:12 -08:00
@@ -225,6 +225,15 @@
 	  If you are compiling a kernel that will run under SGI's IA-64
 	  simulator (Medusa) then say Y, otherwise say N.
 
+config MSPEC
+	tristate "Special Memory support"
+	help
+	  This driver allows for cached and uncached mappings of memory
+	  to user processes. On SGI SN hardware it will also export the
+	  special fetchop memory facility.
+	  Fetchops are atomic memory operations that are implemented in the
+	  memory controller on SGI SN hardware.
+
 config FORCE_MAX_ZONEORDER
 	int
 	default "18"
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/configs/sn2_defconfig linux-2.6.11-rc2-mm2/arch/ia64/configs/sn2_defconfig
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/configs/sn2_defconfig	2005-02-02 04:31:21 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/configs/sn2_defconfig	2005-02-16 04:27:24 -08:00
@@ -82,6 +82,7 @@
 # CONFIG_IA64_CYCLONE is not set
 CONFIG_IOSAPIC=y
 CONFIG_IA64_SGI_SN_SIM=y
+CONFIG_MSPEC=m
 CONFIG_FORCE_MAX_ZONEORDER=18
 CONFIG_SMP=y
 CONFIG_NR_CPUS=512
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/defconfig linux-2.6.11-rc2-mm2/arch/ia64/defconfig
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/defconfig	2005-02-02 04:31:05 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/defconfig	2005-02-16 04:26:50 -08:00
@@ -80,6 +80,7 @@
 CONFIG_DISCONTIGMEM=y
 CONFIG_IA64_CYCLONE=y
 CONFIG_IOSAPIC=y
+CONFIG_MSPEC=m
 CONFIG_FORCE_MAX_ZONEORDER=18
 CONFIG_SMP=y
 CONFIG_NR_CPUS=512
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/Makefile linux-2.6.11-rc2-mm2/arch/ia64/kernel/Makefile
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/Makefile	2005-02-02 04:31:05 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/kernel/Makefile	2005-02-16 04:29:52 -08:00
@@ -7,7 +7,7 @@
 obj-y := acpi.o entry.o efi.o efi_stub.o gate-data.o fsys.o ia64_ksyms.o irq.o irq_ia64.o	\
 	 irq_lsapic.o ivt.o machvec.o pal.o patch.o process.o perfmon.o ptrace.o sal.o		\
 	 salinfo.o semaphore.o setup.o signal.o sys_ia64.o time.o traps.o unaligned.o \
-	 unwind.o mca.o mca_asm.o topology.o
+	 unwind.o mca.o mca_asm.o topology.o mem.o
 
 obj-$(CONFIG_IA64_BRL_EMU)	+= brl_emu.o
 obj-$(CONFIG_IA64_GENERIC)	+= acpi-ext.o
@@ -20,6 +20,7 @@
 obj-$(CONFIG_PERFMON)		+= perfmon_default_smpl.o
 obj-$(CONFIG_IA64_CYCLONE)	+= cyclone.o
 obj-$(CONFIG_IA64_MCA_RECOVERY)	+= mca_recovery.o
+obj-$(CONFIG_MSPEC)		+= mspec.o
 mca_recovery-y			+= mca_drv.o mca_drv_asm.o
 
 # The gate DSO image is built using a special linker script.
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/mem.c linux-2.6.11-rc2-mm2/arch/ia64/kernel/mem.c
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/mem.c	1969-12-31 16:00:00 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/kernel/mem.c	2005-02-16 04:17:09 -08:00
@@ -0,0 +1,151 @@
+/*
+ *  arch/ia64/kernel/mem.c
+ *
+ *  IA64 specific  portions of /dev/mem access, notably handling
+ *  read/write from uncached memory
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 2005 Jes Sorensen <jes@wildopensource.com>
+ */
+
+
+#include <linux/mm.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+
+extern loff_t memory_lseek(struct file * file, loff_t offset, int orig);
+extern int mmap_kmem(struct file * file, struct vm_area_struct * vma);
+extern int open_port(struct inode * inode, struct file * filp);
+
+
+static inline int range_is_allowed(unsigned long from, unsigned long to)
+{
+	unsigned long cursor;
+
+	cursor = from >> PAGE_SHIFT;
+	while ((cursor << PAGE_SHIFT) < to) {
+		if (!devmem_is_allowed(cursor))
+			return 0;
+		cursor++;
+	}
+	return 1;
+}
+
+
+/*
+ * This funcion reads the *physical* memory. The f_pos points directly
+ * to the memory location. 
+ */
+static ssize_t read_mem(struct file * file, char __user * buf,
+			size_t count, loff_t *ppos)
+{
+	unsigned long p = *ppos;
+	ssize_t read, sz;
+	struct page *page;
+	char *ptr;
+
+
+	if (!valid_phys_addr_range(p, &count))
+		return -EFAULT;
+	read = 0;
+
+	while (count > 0) {
+		/*
+		 * Handle first page in case it's not aligned
+		 */
+		if (-p & (PAGE_SIZE - 1))
+			sz = -p & (PAGE_SIZE - 1);
+		else
+			sz = min(PAGE_SIZE, count);
+
+		page = pfn_to_page(p >> PAGE_SHIFT);
+		/*
+		 * On ia64 if a page has been mapped somewhere as
+		 * uncached, then it must also be accessed uncached
+		 * by the kernel or data corruption may occur
+		 */
+		if (page->flags & PG_arch_1)
+			ptr = (char *)p + __IA64_UNCACHED_OFFSET;
+		else
+			ptr = __va(p);
+		if (copy_to_user(buf, ptr, sz))
+			return -EFAULT;
+		buf += sz;
+		p += sz;
+		count -= sz;
+		read += sz;
+	}
+
+	*ppos += read;
+	return read;
+}
+
+
+static ssize_t write_mem(struct file * file, const char __user * buf, 
+			 size_t count, loff_t *ppos)
+{
+	unsigned long p = *ppos;
+	unsigned long copied;
+	ssize_t written, sz;
+	struct page *page;
+	char *ptr;
+
+	if (!valid_phys_addr_range(p, &count))
+		return -EFAULT;
+
+	written = 0;
+
+	if (!range_is_allowed(p, p + count))
+		return -EPERM;
+	/*
+	 * Need virtual p below here
+	 */
+	while (count > 0) {
+		/*
+		 * Handle first page in case it's not aligned
+		 */
+		if (-p & (PAGE_SIZE - 1))
+			sz = -p & (PAGE_SIZE - 1);
+		else
+			sz = min(PAGE_SIZE, count);
+
+		page = pfn_to_page(p >> PAGE_SHIFT);
+		/*
+		 * On ia64 if a page has been mapped somewhere as
+		 * uncached, then it must also be accessed uncached
+		 * by the kernel or data corruption may occur
+		 */
+		if (page->flags & PG_arch_1)
+			ptr = (char *)p + __IA64_UNCACHED_OFFSET;
+		else
+			ptr = __va(p);
+
+		copied = copy_from_user(ptr, buf, sz);
+		if (copied) {
+			ssize_t ret;
+
+			ret = written + (sz - copied);
+			if (ret)
+				return ret;
+			return -EFAULT;
+		}
+		buf += sz;
+		p += sz;
+		count -= sz;
+		written += sz;
+	}
+
+	*ppos += written;
+	return written;
+}
+
+
+struct file_operations mem_fops = {
+	.llseek		= memory_lseek,
+	.read		= read_mem,
+	.write		= write_mem,
+	.mmap		= mmap_kmem,
+	.open		= open_port,
+};
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/mspec.c linux-2.6.11-rc2-mm2/arch/ia64/kernel/mspec.c
--- linux-2.6.11-rc2-mm2-vanilla/arch/ia64/kernel/mspec.c	1969-12-31 16:00:00 -08:00
+++ linux-2.6.11-rc2-mm2/arch/ia64/kernel/mspec.c	2005-02-16 05:12:22 -08:00
@@ -0,0 +1,804 @@
+/*
+ * 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.
+ */
+
+/*
+ * SN Platform Special Memory (mspec) Support
+ *
+ * This driver exports the SN special memory (mspec) facility to user processes.
+ * There are three types of memory made available thru this driver:
+ * fetchops, uncached and cached.
+ *
+ * Fetchops are atomic memory operations that are implemented in the
+ * memory controller on SGI SN hardware.
+ *
+ * Uncached are used for memory write combining feature of the ia64
+ * cpu.
+ *
+ * Cached are used for areas of memory that are used as cached addresses
+ * on our partition and used as uncached addresses from other partitions.
+ * Due to a design constraint of the SN2 Shub, you can not have processors
+ * on the same FSB perform both a cached and uncached reference to the
+ * same cache line.  These special memory cached regions prevent the
+ * kernel from ever dropping in a TLB entry and therefore prevent the
+ * processor from ever speculating a cache line from this page.
+ */
+
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/vmalloc.h>
+#include <linux/bitops.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/seq_file.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/addrs.h>
+#include <asm/sn/arch.h>
+#include <asm/sn/mspec.h>
+#include <asm/sn/sn_cpuid.h>
+#include <asm/sn/io.h>
+#include <asm/sn/bte.h>
+#include <asm/sn/shubio.h>
+
+
+#define DEBUG	0
+
+#define FETCHOP_DRIVER_ID_STR	"MSPEC Fetchop Device Driver"
+#define CACHED_DRIVER_ID_STR	"MSPEC Cached Device Driver"
+#define UNCACHED_DRIVER_ID_STR	"MSPEC Uncached Device Driver"
+#define REVISION		"3.0"
+#define MSPEC_BASENAME		"mspec"
+
+
+#define BTE_ZERO_BLOCK(_maddr, _len) \
+	bte_copy(0, _maddr - __IA64_UNCACHED_OFFSET, _len, BTE_WACQUIRE | BTE_ZERO_FILL, NULL)
+
+static int fetchop_mmap(struct file *file, struct vm_area_struct *vma);
+static int cached_mmap(struct file *file, struct vm_area_struct *vma);
+static int uncached_mmap(struct file *file, struct vm_area_struct *vma);
+static void mspec_open(struct vm_area_struct *vma);
+static void mspec_close(struct vm_area_struct *vma);
+static struct page * mspec_nopage(struct vm_area_struct *vma,
+					unsigned long address, int *unused);
+
+/*
+ * Page types allocated by the device.
+ */
+enum {
+	MSPEC_FETCHOP = 1,
+	MSPEC_CACHED,
+	MSPEC_UNCACHED
+};
+
+static struct file_operations fetchop_fops = {
+	.owner		THIS_MODULE,
+	.mmap		fetchop_mmap
+};
+static struct miscdevice fetchop_miscdev = {
+	.minor		MISC_DYNAMIC_MINOR,
+	.name		"sgi_fetchop",
+	.fops		&fetchop_fops
+};
+
+
+static struct file_operations cached_fops = {
+	.owner		THIS_MODULE,
+	.mmap		cached_mmap
+};
+static struct miscdevice cached_miscdev = {
+	.minor		MISC_DYNAMIC_MINOR,
+	.name		"sgi_cached",
+	.fops		&cached_fops
+};
+
+
+static struct file_operations uncached_fops = {
+	.owner		THIS_MODULE,
+	.mmap		uncached_mmap
+};
+static struct miscdevice uncached_miscdev = {
+	.minor		MISC_DYNAMIC_MINOR,
+	.name		"sgi_uncached",
+	.fops		&uncached_fops
+};
+
+
+static struct vm_operations_struct mspec_vm_ops = {
+	.open		mspec_open,
+	.close		mspec_close,
+	.nopage		mspec_nopage
+};
+
+/*
+ * There is one of these structs per node. It is used to manage the mspec
+ * space that is available on the node. Current assumption is that there is
+ * only 1 mspec block of memory per node.
+ */
+struct node_mspecs {
+	long		maddr;		/* phys addr of start of mspecs. */
+	int		count;		/* Total number of mspec pages. */
+	atomic_t	free;		/* Number of pages currently free. */
+	unsigned long	bits[1];	/* Bitmap for managing pages. */
+};
+
+
+/*
+ * One of these structures is allocated when an mspec region is mmaped. The
+ * structure is pointed to by the vma->vm_private_data field in the vma struct. 
+ * This structure is used to record the addresses of the mspec pages.
+ */
+struct vma_data {
+	atomic_t	refcnt;		/* Number of vmas sharing the data. */
+	spinlock_t	lock;		/* Serialize access to the vma. */
+	int		count;		/* Number of pages allocated. */
+	int		type;		/* Type of pages allocated. */
+	unsigned long	maddr[1];	/* Array of MSPEC addresses. */
+};
+
+
+/*
+ * Memory Special statistics.
+ */
+struct mspec_stats {
+	atomic_t	map_count;	/* Number of active mmap's */
+	atomic_t	pages_in_use;	/* Number of mspec pages in use */
+	unsigned long	pages_total;	/* Total number of mspec pages */
+};
+
+static struct mspec_stats	mspec_stats;
+static struct node_mspecs	*node_mspecs[MAX_NUMNODES];
+
+#define MAX_UNCACHED_GRANULES	5
+static int allocated_granules;
+
+struct gen_pool *mspec_pool[MAX_NUMNODES];
+
+static void mspec_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 mspec_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
+mspec_get_new_chunk(struct gen_pool *poolp)
+{
+	struct page *page;
+	void *tmp;
+	int status, node, i;
+	unsigned long addr;
+
+	if (allocated_granules >= MAX_UNCACHED_GRANULES)
+		return 0;
+
+	node = (int)poolp->private;
+	page = alloc_pages_node(node, GFP_KERNEL,
+				IA64_GRANULE_SHIFT-PAGE_SHIFT);
+
+#if DEBUG
+	printk(KERN_INFO "get_new_chunk page %p, addr %lx\n",
+	       page, (unsigned long)(page-vmem_map) << PAGE_SHIFT);
+#endif
+
+	/*
+	 * Do magic if no mem on local node! XXX
+	 */
+	if (!page)
+		return 0;
+	tmp = page_address(page);
+	memset(tmp, 0, IA64_GRANULE_SIZE);
+
+	/*
+	 * 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++)
+		page[i].flags |= PG_arch_1;
+
+	flush_tlb_kernel_range(tmp, tmp + IA64_GRANULE_SIZE);
+
+	status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
+#if DEBUG
+	printk(KERN_INFO "pal_prefetch_visibility() returns %i on cpu %i\n",
+	       status, get_cpu());
+#endif
+	if (!status) {
+		status = smp_call_function(mspec_ipi_visibility, NULL, 0, 1);
+		if (status)
+			printk(KERN_WARNING "smp_call_function failed for "
+			       "mspec_ipi_visibility! (%i)\n", status);
+	}
+
+	sn_flush_all_caches((unsigned long)tmp, IA64_GRANULE_SIZE);
+	ia64_pal_mc_drain();
+	status = smp_call_function(mspec_ipi_mc_drain, NULL, 0, 1);
+	if (status)
+		printk(KERN_WARNING "smp_call_function failed for "
+		       "mspec_ipi_mc_drain! (%i)\n", status);
+
+	addr = (unsigned long)tmp - PAGE_OFFSET + __IA64_UNCACHED_OFFSET;
+
+	allocated_granules++;
+	return addr;
+}
+
+
+/*
+ * mspec_alloc_page
+ *
+ * Allocate 1 mspec page. Allocates on the requested node. If no
+ * mspec pages are available on the requested node, roundrobin starting
+ * with higher nodes.
+ */
+static unsigned long
+mspec_alloc_page(int nid, int type)
+{
+	unsigned long maddr;
+
+	maddr = gen_pool_alloc(mspec_pool[nid], PAGE_SIZE);
+#if DEBUG
+	printk(KERN_DEBUG "mspec_alloc_page returns %lx on node %i\n",
+	       maddr, nid);
+#endif
+
+	/*
+	 * 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(mspec_pool[i], PAGE_SIZE);
+#if DEBUG
+			printk(KERN_DEBUG "mspec_alloc_page alternate search "
+			       "returns %lx on node %i\n", maddr, i);
+#endif
+			if (maddr) {
+				break;
+			}
+		}
+	}
+
+	if (maddr)
+		atomic_inc(&mspec_stats.pages_in_use);
+
+	return maddr;
+}
+
+
+/*
+ * mspec_free_page
+ *
+ * Free a single mspec page.
+ */
+static void
+mspec_free_page(unsigned long maddr)
+{
+	int node;
+
+	node = nasid_to_cnodeid(NASID_GET(maddr));
+#if DEBUG
+	printk(KERN_DEBUG "mspec_free_page(%lx) on node %i\n", maddr, node);
+#endif
+	if ((maddr & (0XFUL << 60)) != __IA64_UNCACHED_OFFSET)
+		panic("mspec_free_page invalid address %lx\n", maddr); 
+
+	atomic_dec(&mspec_stats.pages_in_use);
+	gen_pool_free(mspec_pool[node], maddr, PAGE_SIZE);
+}
+
+
+/*
+ * mspec_mmap
+ *
+ * Called when mmaping the device.  Initializes the vma with a fault handler
+ * and private data structure necessary to allocate, track, and free the
+ * underlying pages.
+ */
+static int
+mspec_mmap(struct file *file, struct vm_area_struct *vma, int type)
+{
+	struct vma_data *vdata;
+	int pages;
+
+	if (vma->vm_pgoff != 0)
+		return -EINVAL;
+
+	if ((vma->vm_flags & VM_WRITE) == 0)
+		return -EPERM;
+
+	pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	if (!(vdata = vmalloc(sizeof(struct vma_data)+(pages-1)*sizeof(long))))
+		return -ENOMEM;
+	memset(vdata, 0, sizeof(struct vma_data)+(pages-1)*sizeof(long));
+
+	vdata->type = type;
+	vdata->lock = SPIN_LOCK_UNLOCKED;
+	vdata->refcnt = ATOMIC_INIT(1);
+	vma->vm_private_data = vdata;
+
+	vma->vm_flags |= (VM_IO | VM_SHM | VM_LOCKED);
+	if (vdata->type == MSPEC_FETCHOP || vdata->type == MSPEC_UNCACHED)
+		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	vma->vm_ops = &mspec_vm_ops;
+
+	atomic_inc(&mspec_stats.map_count);
+	return 0;
+}
+
+static int
+fetchop_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return mspec_mmap(file, vma, MSPEC_FETCHOP);
+}
+
+static int
+cached_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return mspec_mmap(file, vma, MSPEC_CACHED);
+}
+
+static int
+uncached_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return mspec_mmap(file, vma, MSPEC_UNCACHED);
+}
+
+/*
+ * mspec_open
+ *
+ * Called when a device mapping is created by a means other than mmap
+ * (via fork, etc.).  Increments the reference count on the underlying
+ * mspec data so it is not freed prematurely.
+ */
+static void
+mspec_open(struct vm_area_struct *vma)
+{
+	struct vma_data *vdata;
+
+	vdata = vma->vm_private_data;
+	atomic_inc(&vdata->refcnt);
+}
+
+/*
+ * mspec_close
+ *
+ * Called when unmapping a device mapping. Frees all mspec pages
+ * belonging to the vma.
+ */
+static void
+mspec_close(struct vm_area_struct *vma)
+{
+	struct vma_data *vdata;
+	int i, pages;
+	bte_result_t br;
+
+	vdata = vma->vm_private_data;
+	if (atomic_dec(&vdata->refcnt) == 0) {
+		pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+		for (i = 0; i < pages; i++) {
+			if (vdata->maddr[i] != 0) {
+				/*
+				 * Clear the page before sticking it back 
+				 * into the pool.
+				 */
+				br = BTE_ZERO_BLOCK(vdata->maddr[i], PAGE_SIZE);
+				if (br == BTE_SUCCESS)
+					mspec_free_page(vdata->maddr[i]);
+				else
+					printk(KERN_WARNING "mspec_close(): BTE failed to zero page\n");
+			}
+		}
+		if (vdata->count) 
+			atomic_dec(&mspec_stats.map_count);
+		vfree(vdata);
+	}
+}
+
+/*
+ * mspec_get_one_pte
+ *
+ * Return the pte for a given mm and address.
+ */
+static __inline__ int
+mspec_get_one_pte(struct mm_struct *mm, u64 address, pte_t **pte)
+{
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pud_t *pud;
+
+	pgd = pgd_offset(mm, address);
+	if (pgd_present(*pgd)) {
+		pud = pud_offset(pgd, address);
+		if (pud_present(*pud)) {
+			pmd = pmd_offset(pud, address);
+			if (pmd_present(*pmd)) {
+				*pte = pte_offset_map(pmd, address);
+				if (pte_present(**pte)) {
+					return 0;
+				}
+			}
+		}
+	}
+
+	return -1;
+}
+
+/*
+ * mspec_nopage
+ *
+ * Creates a mspec page and maps it to user space.
+ */
+static struct page *
+mspec_nopage(struct vm_area_struct *vma, unsigned long address, int *unused)
+{
+	unsigned long paddr, maddr = 0;
+	unsigned long pfn;
+	int index;
+	pte_t *pte;
+	struct page *page;
+	struct vma_data *vdata = vma->vm_private_data;
+
+	spin_lock(&vdata->lock);
+
+	index = (address - vma->vm_start) >> PAGE_SHIFT;
+	if (vdata->maddr[index] == 0) {
+		vdata->count++;
+		maddr = mspec_alloc_page(numa_node_id(), vdata->type);
+		if (maddr == 0)
+			BUG();
+		vdata->maddr[index] = maddr;
+	} else if (mspec_get_one_pte(vma->vm_mm, address, &pte) == 0) {
+		printk(KERN_ERR "page already mapped\n");
+		/*
+		 * The page may have already been faulted by another
+		 * pthread.  If so, we need to avoid remapping the
+		 * page or we will trip a BUG check in the
+		 * remap_page_range() path.
+		 */
+		goto getpage;
+	}
+
+	if (vdata->type == MSPEC_FETCHOP)
+		paddr = TO_AMO(vdata->maddr[index]);
+	else
+		paddr = __pa(TO_CAC(vdata->maddr[index]));
+
+	/*
+	 * XXX - is this correct?
+	 */
+	pfn = paddr >> PAGE_SHIFT;
+	if (remap_pfn_range(vma, address, pfn, PAGE_SIZE, vma->vm_page_prot)) {
+		printk(KERN_ERR "remap_pfn_range failed!\n");
+		goto error;
+	}
+
+	/*
+	 * The kernel requires a page structure to be returned upon
+	 * success, but there are no page structures for low granule pages.
+	 * remap_page_range() creates the pte for us and we return a
+	 * bogus page back to the kernel fault handler to keep it happy
+	 * (the page is freed immediately there).
+	 */
+	if (mspec_get_one_pte(vma->vm_mm, address, &pte) == 0) {
+		spin_lock(&vma->vm_mm->page_table_lock);
+		vma->vm_mm->rss++;
+		spin_unlock(&vma->vm_mm->page_table_lock);
+
+		set_pte(pte, pte_mkwrite(pte_mkdirty(*pte)));
+	}
+getpage:
+	/*
+	 * Is this really correct?
+	 */
+	page = alloc_pages(GFP_USER, 0);
+	spin_unlock(&vdata->lock);
+	return page;
+#if 0
+	page = pfn_to_page(pfn);
+	printk(KERN_ERR "fall through!\n");
+	goto getpage;
+	return page;
+#endif
+error:
+	if (maddr) {
+		mspec_free_page(vdata->maddr[index]);
+		vdata->maddr[index] = 0;
+		vdata->count--;
+	}
+	spin_unlock(&vdata->lock);
+	return NOPAGE_SIGBUS;
+}
+
+
+#ifdef CONFIG_PROC_FS
+static void *
+mspec_seq_start(struct seq_file *file, loff_t *offset)
+{
+	if (*offset < MAX_NUMNODES)
+		return offset;
+	return NULL;			
+}
+
+static void *
+mspec_seq_next(struct seq_file *file, void *data, loff_t *offset)
+{
+	(*offset)++;
+	if (*offset < MAX_NUMNODES)
+		return offset;
+	return NULL;
+}
+
+static void
+mspec_seq_stop(struct seq_file *file, void *data)
+{
+}
+
+static int
+mspec_seq_show(struct seq_file *file, void *data)
+{
+	struct node_mspecs *mspecs;
+	int i;
+
+	i = *(loff_t *)data;
+
+	if (!i) {
+		seq_printf(file, "mappings               : %i\n",
+			   atomic_read(&mspec_stats.map_count));
+		seq_printf(file, "current mspec pages    : %i\n",
+			   atomic_read(&mspec_stats.pages_in_use));
+		seq_printf(file, "%4s %7s %7s\n", "node", "total", "free");
+	}
+
+	if (i < MAX_NUMNODES) {
+		int free, count;
+		mspecs = node_mspecs[i];
+		if (mspecs) {
+			free = atomic_read(&mspecs->free);
+			count = mspecs->count;
+			seq_printf(file, "%4d %7d %7d\n", i, count, free);
+		}
+	}
+
+	return 0;
+}
+
+
+static struct seq_operations mspec_seq_ops = {
+	.start = mspec_seq_start,
+	.next = mspec_seq_next,
+	.stop = mspec_seq_stop,
+	.show = mspec_seq_show
+};
+
+int
+mspec_proc_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &mspec_seq_ops);
+}
+
+static struct file_operations proc_mspec_operations = {
+	.open		= mspec_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+
+static struct proc_dir_entry   *proc_mspec;
+
+#endif /* CONFIG_PROC_FS */
+
+/*
+ * mspec_build_memmap,
+ *
+ * Called at boot time to build a map of pages that can be used for
+ * memory special operations.
+ */
+static int __init
+mspec_build_memmap(unsigned long start, unsigned long end)
+{
+	long length;
+	bte_result_t br;
+	unsigned long vstart, vend;
+	int node;
+
+	length = end - start;
+	vstart = start + __IA64_UNCACHED_OFFSET;
+	vend = end + __IA64_UNCACHED_OFFSET;
+
+#if DEBUG
+	printk(KERN_ERR "mspec_build_memmap(%lx %lx)\n", start, end);
+#endif
+
+	br = BTE_ZERO_BLOCK(vstart, length);
+	if (br != BTE_SUCCESS)
+		panic("BTE Failed while trying to zero mspec page.  bte_result_t = %d\n", (int) br);
+
+	node = nasid_to_cnodeid(NASID_GET(start));
+
+	for (; vstart < vend ; vstart += PAGE_SIZE) {
+#if DEBUG
+		printk(KERN_INFO "sticking %lx into the pool!\n", vstart);
+#endif
+		gen_pool_free(mspec_pool[node], vstart, PAGE_SIZE);
+	}
+
+	return 0;
+}
+
+/*
+ * 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
+ */
+static void __init
+mspec_walk_efi_memmap_uc (void)
+{
+	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 (mspec_build_memmap(start, end) < 0)
+				return;
+		}
+	}
+}
+
+
+
+/*
+ * mspec_init
+ *
+ * Called at boot time to initialize the mspec facility.
+ */
+static int __init
+mspec_init(void)
+{
+	int i, ret;
+
+	/*
+	 * The fetchop device only works on SN2 hardware, uncached and cached
+	 * memory drivers should both be valid on all ia64 hardware
+	 */
+	if (ia64_platform_is("sn2")) {
+		if ((ret = misc_register(&fetchop_miscdev))) {
+			printk(KERN_ERR "%s: failed to register device %i\n",
+			       FETCHOP_DRIVER_ID_STR, ret);
+			return ret;
+		}
+	}
+	if ((ret = misc_register(&cached_miscdev))) {
+		printk(KERN_ERR "%s: failed to register device %i\n",
+		       CACHED_DRIVER_ID_STR, ret);
+		misc_deregister(&fetchop_miscdev);
+		return ret;
+	}
+	if ((ret = misc_register(&uncached_miscdev))) {
+		printk(KERN_ERR "%s: failed to register device %i\n",
+		       UNCACHED_DRIVER_ID_STR, ret);
+		misc_deregister(&cached_miscdev);
+		misc_deregister(&fetchop_miscdev);
+		return ret;
+	}
+
+	/*
+	 * /proc code needs to be updated to work with the new
+	 * allocation scheme
+	 */
+#ifdef CONFIG_PROC_FS
+	if (!(proc_mspec = create_proc_entry(MSPEC_BASENAME, 0444, NULL))){
+		printk(KERN_ERR "%s: unable to create proc entry",
+		       FETCHOP_DRIVER_ID_STR);
+		misc_deregister(&uncached_miscdev);
+		misc_deregister(&cached_miscdev);
+		misc_deregister(&fetchop_miscdev);
+		return -EINVAL;
+	}
+	proc_mspec->proc_fops = &proc_mspec_operations;
+#endif /* CONFIG_PROC_FS */
+
+	for (i = 0; i < MAX_NUMNODES; i++) {
+		if (!node_online(i))
+			continue;
+		printk(KERN_DEBUG "Setting up pool for node %i\n", i);
+		mspec_pool[i] = alloc_gen_pool(0, IA64_GRANULE_SHIFT,
+					       &mspec_get_new_chunk, i);
+	}
+
+	mspec_walk_efi_memmap_uc();
+
+	printk(KERN_INFO "%s: v%s\n", FETCHOP_DRIVER_ID_STR, REVISION);
+	printk(KERN_INFO "%s: v%s\n", CACHED_DRIVER_ID_STR, REVISION);
+	printk(KERN_INFO "%s: v%s\n", UNCACHED_DRIVER_ID_STR, REVISION);
+
+	return 0;
+}
+
+
+static void __exit
+mspec_exit(void)
+{
+	BUG_ON(atomic_read(&mspec_stats.pages_in_use) > 0);
+
+#ifdef CONFIG_PROC_FS
+	remove_proc_entry(MSPEC_BASENAME, NULL);
+#endif
+	misc_deregister(&uncached_miscdev);
+	misc_deregister(&cached_miscdev);
+	misc_deregister(&fetchop_miscdev);
+}
+
+
+unsigned long
+mspec_kalloc_page(int nid)
+{
+	return TO_AMO(mspec_alloc_page(nid, MSPEC_FETCHOP));
+}
+
+
+void
+mspec_kfree_page(unsigned long maddr)
+{
+	mspec_free_page(TO_PHYS(maddr) + __IA64_UNCACHED_OFFSET);
+}
+EXPORT_SYMBOL(mspec_kalloc_page);
+EXPORT_SYMBOL(mspec_kfree_page);
+
+
+module_init(mspec_init);
+module_exit(mspec_exit);
+
+
+MODULE_AUTHOR("Silicon Graphics, Inc.");
+MODULE_DESCRIPTION("Driver for SGI SN special memory operations");
+MODULE_LICENSE("GPL");
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/drivers/char/mem.c linux-2.6.11-rc2-mm2/drivers/char/mem.c
--- linux-2.6.11-rc2-mm2-vanilla/drivers/char/mem.c	2005-02-02 04:31:22 -08:00
+++ linux-2.6.11-rc2-mm2/drivers/char/mem.c	2005-02-16 04:23:20 -08:00
@@ -125,39 +125,7 @@
 	}
 	return 1;
 }
-static ssize_t do_write_mem(void *p, unsigned long realp,
-			    const char __user * buf, size_t count, loff_t *ppos)
-{
-	ssize_t written;
-	unsigned long copied;
-
-	written = 0;
-#if defined(__sparc__) || (defined(__mc68000__) && defined(CONFIG_MMU))
-	/* we don't have page 0 mapped on sparc and m68k.. */
-	if (realp < PAGE_SIZE) {
-		unsigned long sz = PAGE_SIZE-realp;
-		if (sz > count) sz = count; 
-		/* Hmm. Do something? */
-		buf+=sz;
-		p+=sz;
-		count-=sz;
-		written+=sz;
-	}
-#endif
-	if (!range_is_allowed(realp, realp+count))
-		return -EPERM;
-	copied = copy_from_user(p, buf, count);
-	if (copied) {
-		ssize_t ret = written + (count - copied);
 
-		if (ret)
-			return ret;
-		return -EFAULT;
-	}
-	written += count;
-	*ppos += written;
-	return written;
-}
 
 #ifndef ARCH_HAS_DEV_MEM
 /*
@@ -196,6 +164,40 @@
 	return read;
 }
 
+static ssize_t do_write_mem(void *p, unsigned long realp,
+			    const char __user * buf, size_t count, loff_t *ppos)
+{
+	ssize_t written;
+	unsigned long copied;
+
+	written = 0;
+#if defined(__sparc__) || (defined(__mc68000__) && defined(CONFIG_MMU))
+	/* we don't have page 0 mapped on sparc and m68k.. */
+	if (realp < PAGE_SIZE) {
+		unsigned long sz = PAGE_SIZE-realp;
+		if (sz > count) sz = count; 
+		/* Hmm. Do something? */
+		buf+=sz;
+		p+=sz;
+		count-=sz;
+		written+=sz;
+	}
+#endif
+	if (!range_is_allowed(realp, realp+count))
+		return -EPERM;
+	copied = copy_from_user(p, buf, count);
+	if (copied) {
+		ssize_t ret = written + (count - copied);
+
+		if (ret)
+			return ret;
+		return -EFAULT;
+	}
+	written += count;
+	*ppos += written;
+	return written;
+}
+
 static ssize_t write_mem(struct file * file, const char __user * buf, 
 			 size_t count, loff_t *ppos)
 {
@@ -207,7 +209,8 @@
 }
 #endif
 
-static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
+
+int mmap_kmem(struct file * file, struct vm_area_struct * vma)
 {
 #ifdef pgprot_noncached
 	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
@@ -553,7 +556,7 @@
  * also note that seeking relative to the "end of file" isn't supported:
  * it has no meaning, so it returns -EINVAL.
  */
-static loff_t memory_lseek(struct file * file, loff_t offset, int orig)
+loff_t memory_lseek(struct file * file, loff_t offset, int orig)
 {
 	loff_t ret;
 
@@ -576,7 +579,7 @@
 	return ret;
 }
 
-static int open_port(struct inode * inode, struct file * filp)
+int open_port(struct inode * inode, struct file * filp)
 {
 	return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
 }
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/io.h linux-2.6.11-rc2-mm2/include/asm-ia64/io.h
--- linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/io.h	2005-02-02 04:31:11 -08:00
+++ linux-2.6.11-rc2-mm2/include/asm-ia64/io.h	2005-02-16 02:38:18 -08:00
@@ -481,4 +481,6 @@
 #define BIO_VMERGE_BOUNDARY	(ia64_max_iommu_merge_mask + 1)
 #endif
 
+#define ARCH_HAS_DEV_MEM
+
 #endif /* _ASM_IA64_IO_H */
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/sn/fetchop.h linux-2.6.11-rc2-mm2/include/asm-ia64/sn/fetchop.h
--- linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/sn/fetchop.h	2004-12-24 13:35:00 -08:00
+++ linux-2.6.11-rc2-mm2/include/asm-ia64/sn/fetchop.h	1969-12-31 16:00:00 -08:00
@@ -1,85 +0,0 @@
-/*
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (c) 2001-2004 Silicon Graphics, Inc.  All rights reserved.
- */
-
-#ifndef _ASM_IA64_SN_FETCHOP_H
-#define _ASM_IA64_SN_FETCHOP_H
-
-#include <linux/config.h>
-
-#define FETCHOP_BASENAME	"sgi_fetchop"
-#define FETCHOP_FULLNAME	"/dev/sgi_fetchop"
-
-
-
-#define FETCHOP_VAR_SIZE 64 /* 64 byte per fetchop variable */
-
-#define FETCHOP_LOAD		0
-#define FETCHOP_INCREMENT	8
-#define FETCHOP_DECREMENT	16
-#define FETCHOP_CLEAR		24
-
-#define FETCHOP_STORE		0
-#define FETCHOP_AND		24
-#define FETCHOP_OR		32
-
-#define FETCHOP_CLEAR_CACHE	56
-
-#define FETCHOP_LOAD_OP(addr, op) ( \
-         *(volatile long *)((char*) (addr) + (op)))
-
-#define FETCHOP_STORE_OP(addr, op, x) ( \
-         *(volatile long *)((char*) (addr) + (op)) = (long) (x))
-
-#ifdef __KERNEL__
-
-/*
- * Convert a region 6 (kaddr) address to the address of the fetchop variable
- */
-#define FETCHOP_KADDR_TO_MSPEC_ADDR(kaddr)	TO_MSPEC(kaddr)
-
-
-/*
- * Each Atomic Memory Operation (AMO formerly known as fetchop)
- * variable is 64 bytes long.  The first 8 bytes are used.  The
- * remaining 56 bytes are unaddressable due to the operation taking
- * that portion of the address.
- * 
- * NOTE: The AMO_t _MUST_ be placed in either the first or second half
- * of the cache line.  The cache line _MUST NOT_ be used for anything
- * other than additional AMO_t entries.  This is because there are two
- * addresses which reference the same physical cache line.  One will
- * be a cached entry with the memory type bits all set.  This address
- * may be loaded into processor cache.  The AMO_t will be referenced
- * uncached via the memory special memory type.  If any portion of the
- * cached cache-line is modified, when that line is flushed, it will
- * overwrite the uncached value in physical memory and lead to
- * inconsistency.
- */
-typedef struct {
-        u64 variable;
-        u64 unused[7];
-} AMO_t;
-
-
-/*
- * The following APIs are externalized to the kernel to allocate/free pages of
- * fetchop variables.
- *	fetchop_kalloc_page	- Allocate/initialize 1 fetchop page on the
- *				  specified cnode. 
- *	fetchop_kfree_page	- Free a previously allocated fetchop page
- */
-
-unsigned long fetchop_kalloc_page(int nid);
-void fetchop_kfree_page(unsigned long maddr);
-
-
-#endif /* __KERNEL__ */
-
-#endif /* _ASM_IA64_SN_FETCHOP_H */
-
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/sn/mspec.h linux-2.6.11-rc2-mm2/include/asm-ia64/sn/mspec.h
--- linux-2.6.11-rc2-mm2-vanilla/include/asm-ia64/sn/mspec.h	1969-12-31 16:00:00 -08:00
+++ linux-2.6.11-rc2-mm2/include/asm-ia64/sn/mspec.h	2005-02-02 04:52:48 -08:00
@@ -0,0 +1,72 @@
+/*
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2001-2004 Silicon Graphics, Inc.  All rights reserved.
+ */
+
+#ifndef _ASM_IA64_SN_MSPEC_H
+#define _ASM_IA64_SN_MSPEC_H
+
+#define FETCHOP_VAR_SIZE 64 /* 64 byte per fetchop variable */
+
+#define FETCHOP_LOAD		0
+#define FETCHOP_INCREMENT	8
+#define FETCHOP_DECREMENT	16
+#define FETCHOP_CLEAR		24
+
+#define FETCHOP_STORE		0
+#define FETCHOP_AND		24
+#define FETCHOP_OR		32
+
+#define FETCHOP_CLEAR_CACHE	56
+
+#define FETCHOP_LOAD_OP(addr, op) ( \
+         *(volatile long *)((char*) (addr) + (op)))
+
+#define FETCHOP_STORE_OP(addr, op, x) ( \
+         *(volatile long *)((char*) (addr) + (op)) = (long) (x))
+
+#ifdef __KERNEL__
+
+/*
+ * Each Atomic Memory Operation (AMO formerly known as fetchop)
+ * variable is 64 bytes long.  The first 8 bytes are used.  The
+ * remaining 56 bytes are unaddressable due to the operation taking
+ * that portion of the address.
+ * 
+ * NOTE: The AMO_t _MUST_ be placed in either the first or second half
+ * of the cache line.  The cache line _MUST NOT_ be used for anything
+ * other than additional AMO_t entries.  This is because there are two
+ * addresses which reference the same physical cache line.  One will
+ * be a cached entry with the memory type bits all set.  This address
+ * may be loaded into processor cache.  The AMO_t will be referenced
+ * uncached via the memory special memory type.  If any portion of the
+ * cached cache-line is modified, when that line is flushed, it will
+ * overwrite the uncached value in physical memory and lead to
+ * inconsistency.
+ */
+typedef struct {
+        u64 variable;
+        u64 unused[7];
+} AMO_t;
+
+
+/*
+ * The following APIs are externalized to the kernel to allocate/free pages of
+ * fetchop variables.
+ *	mspec_kalloc_page	- Allocate/initialize 1 fetchop page on the
+ *				  specified cnode. 
+ *	mspec_kfree_page	- Free a previously allocated fetchop page
+ */
+
+extern unsigned long mspec_kalloc_page(int);
+extern void mspec_kfree_page(unsigned long);
+
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_IA64_SN_MSPEC_H */
+
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/include/linux/genalloc.h linux-2.6.11-rc2-mm2/include/linux/genalloc.h
--- linux-2.6.11-rc2-mm2-vanilla/include/linux/genalloc.h	1969-12-31 16:00:00 -08:00
+++ linux-2.6.11-rc2-mm2/include/linux/genalloc.h	2005-02-02 04:52:48 -08:00
@@ -0,0 +1,46 @@
+/*
+ * 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 of a given kind.
+ *  Ideally, we want to use:
+ *  1) 1 pool for memory we donnot need to involve in DMA.
+ *  2) The same pool for controllers that require same DMA 
+ *     constraints and features.
+ *     The OS specific m_pool_id_t thing and the gen_pool_match() 
+ *     method are expected to tell the driver about.
+ */
+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 *alloc_gen_pool(int nr_chunks, int max_chunk_shift,
+				unsigned long (*fp)(struct gen_pool *),
+				unsigned long data);
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/init/main.c linux-2.6.11-rc2-mm2/init/main.c
--- linux-2.6.11-rc2-mm2-vanilla/init/main.c	2005-02-02 04:31:24 -08:00
+++ linux-2.6.11-rc2-mm2/init/main.c	2005-02-02 04:52:48 -08:00
@@ -78,6 +78,7 @@
 
 static int init(void *);
 
+extern void gen_pool_init(void);
 extern void init_IRQ(void);
 extern void sock_init(void);
 extern void fork_init(unsigned long);
@@ -482,6 +483,7 @@
 #endif
 	vfs_caches_init_early();
 	mem_init();
+	gen_pool_init();
 	kmem_cache_init();
 	numa_policy_init();
 	if (late_time_init)
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/lib/Makefile linux-2.6.11-rc2-mm2/lib/Makefile
--- linux-2.6.11-rc2-mm2-vanilla/lib/Makefile	2005-02-02 04:31:24 -08:00
+++ linux-2.6.11-rc2-mm2/lib/Makefile	2005-02-02 04:54:02 -08:00
@@ -6,7 +6,7 @@
 	 bust_spinlocks.o rbtree.o radix-tree.o dump_stack.o \
 	 kobject.o kref.o idr.o div64.o parser.o int_sqrt.o \
 	 bitmap.o extable.o kobject_uevent.o prio_tree.o \
-	 sha1.o halfmd4.o
+	 sha1.o halfmd4.o genalloc.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
diff -X /usr/people/jes/exclude-linux -urN linux-2.6.11-rc2-mm2-vanilla/lib/genalloc.c linux-2.6.11-rc2-mm2/lib/genalloc.c
--- linux-2.6.11-rc2-mm2-vanilla/lib/genalloc.c	1969-12-31 16:00:00 -08:00
+++ linux-2.6.11-rc2-mm2/lib/genalloc.c	2005-02-02 04:52:48 -08:00
@@ -0,0 +1,218 @@
+/*
+ * 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.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/config.h>
+#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>
+#include <asm/pal.h>
+
+
+#define DEBUG	0
+
+struct gen_pool *alloc_gen_pool(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.
+	 */
+	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;
+}
+
+
+/*
+ *  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;
+	s = (1 << ALLOC_MIN_SHIFT);
+	while (size > s) {
+		s <<= 1;
+		i++;
+	}
+
+#if DEBUG
+	printk(KERN_DEBUG "gen_pool_alloc: s %02x, i %i, h %p\n", s, i, h);
+#endif
+
+	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;
+#if DEBUG
+			printk(KERN_DEBUG "gen_pool_alloc() max chunk j %i\n", j);
+#endif
+			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) {
+#if DEBUG
+			printk(KERN_DEBUG "gen_pool_alloc() splitting i %i j %i %x a %02lx\n", i, j, s, a);
+#endif
+			j -= 1;
+			s >>= 1;
+			h[j].next = (struct gen_pool_link *) (a + s);
+			h[j].next->next = NULL;
+		}
+	}
+	spin_unlock_irqrestore(&poolp->lock, flags);
+#if DEBUG
+	printk(KERN_DEBUG "gen_pool_alloc(%d) = %p\n", size, (void *) a);
+#endif
+	return a;
+}
+
+/*
+ *  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, max_chunk_size;
+	int s = (1 << ALLOC_MIN_SHIFT);
+
+#if DEBUG
+	printk(KERN_DEBUG "gen_pool_free(%lx, %d)\n", ptr, size);
+#endif
+
+	max_chunk_size = 1 << poolp->max_chunk_shift;
+
+	if (size > max_chunk_size)
+		return;
+
+	i = 0;
+	while (size > s) {
+		s <<= 1;
+		i++;
+	}
+
+	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);
+}
+
+
+int __init gen_pool_init(void)
+{
+	printk(KERN_INFO "Generic memory pool allocator v1.0\n");
+	return 0;
+}
+
+EXPORT_SYMBOL(alloc_gen_pool);
+EXPORT_SYMBOL(gen_pool_alloc);
+EXPORT_SYMBOL(gen_pool_free);
-
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Received on Wed Feb 16 09:22:01 2005

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:35 EST