Merge branch 'master'

11 files changed, 488 insertions, 41 deletions

diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index 01a1bd239263..2143609d2936 100644
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -200,8 +200,7 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
 	 * Note: Assume that this function returns zero on success
 	 */
 	result = add_memory(mem_device->start_addr,
-			    (mem_device->end_addr - mem_device->start_addr) + 1,
-			    mem_device->read_write_attribute);
+			    (mem_device->end_addr - mem_device->start_addr) + 1);
 	if (result) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "\nadd_memory failed\n"));
 		mem_device->state = MEMORY_INVALID_STATE;
@@ -259,7 +258,7 @@ static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
 	 * Ask the VM to offline this memory range.
 	 * Note: Assume that this function returns zero on success
 	 */
-	result = remove_memory(start, len, attr);
+	result = remove_memory(start, len);
 	if (result) {
 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Hot-Remove failed.\n"));
 		return_VALUE(result);
diff --git a/drivers/base/Makefile b/drivers/base/Makefile
index 66d9c4643fc1..f12898d53078 100644
--- a/drivers/base/Makefile
+++ b/drivers/base/Makefile
@@ -7,6 +7,7 @@ obj-y			:= core.o sys.o bus.o dd.o \
 obj-y			+= power/
 obj-$(CONFIG_FW_LOADER)	+= firmware_class.o
 obj-$(CONFIG_NUMA)	+= node.o
+obj-$(CONFIG_MEMORY_HOTPLUG) += memory.o
 
 ifeq ($(CONFIG_DEBUG_DRIVER),y)
 EXTRA_CFLAGS += -DDEBUG
diff --git a/drivers/base/init.c b/drivers/base/init.c
index 84e604e25c4f..c648914b9cde 100644
--- a/drivers/base/init.c
+++ b/drivers/base/init.c
@@ -9,6 +9,7 @@
 
 #include <linux/device.h>
 #include <linux/init.h>
+#include <linux/memory.h>
 
 #include "base.h"
 
@@ -33,5 +34,6 @@ void __init driver_init(void)
 	platform_bus_init();
 	system_bus_init();
 	cpu_dev_init();
+	memory_dev_init();
 	attribute_container_init();
 }
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
new file mode 100644
index 000000000000..b7ddd651d664
--- /dev/null
+++ b/drivers/base/memory.c
@@ -0,0 +1,452 @@
+/*
+ * drivers/base/memory.c - basic Memory class support
+ *
+ * Written by Matt Tolentino <matthew.e.tolentino@intel.com>
+ *            Dave Hansen <haveblue@us.ibm.com>
+ *
+ * This file provides the necessary infrastructure to represent
+ * a SPARSEMEM-memory-model system's physical memory in /sysfs.
+ * All arch-independent code that assumes MEMORY_HOTPLUG requires
+ * SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
+ */
+
+#include <linux/sysdev.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>	/* capable() */
+#include <linux/topology.h>
+#include <linux/device.h>
+#include <linux/memory.h>
+#include <linux/kobject.h>
+#include <linux/memory_hotplug.h>
+#include <linux/mm.h>
+#include <asm/atomic.h>
+#include <asm/uaccess.h>
+
+#define MEMORY_CLASS_NAME	"memory"
+
+static struct sysdev_class memory_sysdev_class = {
+	set_kset_name(MEMORY_CLASS_NAME),
+};
+EXPORT_SYMBOL(memory_sysdev_class);
+
+static char *memory_hotplug_name(struct kset *kset, struct kobject *kobj)
+{
+	return MEMORY_CLASS_NAME;
+}
+
+static int memory_hotplug(struct kset *kset, struct kobject *kobj, char **envp,
+			int num_envp, char *buffer, int buffer_size)
+{
+	int retval = 0;
+
+	return retval;
+}
+
+static struct kset_hotplug_ops memory_hotplug_ops = {
+	.name		= memory_hotplug_name,
+	.hotplug	= memory_hotplug,
+};
+
+static struct notifier_block *memory_chain;
+
+static int register_memory_notifier(struct notifier_block *nb)
+{
+        return notifier_chain_register(&memory_chain, nb);
+}
+
+static void unregister_memory_notifier(struct notifier_block *nb)
+{
+        notifier_chain_unregister(&memory_chain, nb);
+}
+
+/*
+ * register_memory - Setup a sysfs device for a memory block
+ */
+static int
+register_memory(struct memory_block *memory, struct mem_section *section,
+		struct node *root)
+{
+	int error;
+
+	memory->sysdev.cls = &memory_sysdev_class;
+	memory->sysdev.id = __section_nr(section);
+
+	error = sysdev_register(&memory->sysdev);
+
+	if (root && !error)
+		error = sysfs_create_link(&root->sysdev.kobj,
+					  &memory->sysdev.kobj,
+					  kobject_name(&memory->sysdev.kobj));
+
+	return error;
+}
+
+static void
+unregister_memory(struct memory_block *memory, struct mem_section *section,
+		struct node *root)
+{
+	BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
+	BUG_ON(memory->sysdev.id != __section_nr(section));
+
+	sysdev_unregister(&memory->sysdev);
+	if (root)
+		sysfs_remove_link(&root->sysdev.kobj,
+				  kobject_name(&memory->sysdev.kobj));
+}
+
+/*
+ * use this as the physical section index that this memsection
+ * uses.
+ */
+
+static ssize_t show_mem_phys_index(struct sys_device *dev, char *buf)
+{
+	struct memory_block *mem =
+		container_of(dev, struct memory_block, sysdev);
+	return sprintf(buf, "%08lx\n", mem->phys_index);
+}
+
+/*
+ * online, offline, going offline, etc.
+ */
+static ssize_t show_mem_state(struct sys_device *dev, char *buf)
+{
+	struct memory_block *mem =
+		container_of(dev, struct memory_block, sysdev);
+	ssize_t len = 0;
+
+	/*
+	 * We can probably put these states in a nice little array
+	 * so that they're not open-coded
+	 */
+	switch (mem->state) {
+		case MEM_ONLINE:
+			len = sprintf(buf, "online\n");
+			break;
+		case MEM_OFFLINE:
+			len = sprintf(buf, "offline\n");
+			break;
+		case MEM_GOING_OFFLINE:
+			len = sprintf(buf, "going-offline\n");
+			break;
+		default:
+			len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
+					mem->state);
+			WARN_ON(1);
+			break;
+	}
+
+	return len;
+}
+
+static inline int memory_notify(unsigned long val, void *v)
+{
+	return notifier_call_chain(&memory_chain, val, v);
+}
+
+/*
+ * MEMORY_HOTPLUG depends on SPARSEMEM in mm/Kconfig, so it is
+ * OK to have direct references to sparsemem variables in here.
+ */
+static int
+memory_block_action(struct memory_block *mem, unsigned long action)
+{
+	int i;
+	unsigned long psection;
+	unsigned long start_pfn, start_paddr;
+	struct page *first_page;
+	int ret;
+	int old_state = mem->state;
+
+	psection = mem->phys_index;
+	first_page = pfn_to_page(psection << PFN_SECTION_SHIFT);
+
+	/*
+	 * The probe routines leave the pages reserved, just
+	 * as the bootmem code does.  Make sure they're still
+	 * that way.
+	 */
+	if (action == MEM_ONLINE) {
+		for (i = 0; i < PAGES_PER_SECTION; i++) {
+			if (PageReserved(first_page+i))
+				continue;
+
+			printk(KERN_WARNING "section number %ld page number %d "
+				"not reserved, was it already online? \n",
+				psection, i);
+			return -EBUSY;
+		}
+	}
+
+	switch (action) {
+		case MEM_ONLINE:
+			start_pfn = page_to_pfn(first_page);
+			ret = online_pages(start_pfn, PAGES_PER_SECTION);
+			break;
+		case MEM_OFFLINE:
+			mem->state = MEM_GOING_OFFLINE;
+			memory_notify(MEM_GOING_OFFLINE, NULL);
+			start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
+			ret = remove_memory(start_paddr,
+					    PAGES_PER_SECTION << PAGE_SHIFT);
+			if (ret) {
+				mem->state = old_state;
+				break;
+			}
+			memory_notify(MEM_MAPPING_INVALID, NULL);
+			break;
+		default:
+			printk(KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
+					__FUNCTION__, mem, action, action);
+			WARN_ON(1);
+			ret = -EINVAL;
+	}
+	/*
+	 * For now, only notify on successful memory operations
+	 */
+	if (!ret)
+		memory_notify(action, NULL);
+
+	return ret;
+}
+
+static int memory_block_change_state(struct memory_block *mem,
+		unsigned long to_state, unsigned long from_state_req)
+{
+	int ret = 0;
+	down(&mem->state_sem);
+
+	if (mem->state != from_state_req) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = memory_block_action(mem, to_state);
+	if (!ret)
+		mem->state = to_state;
+
+out:
+	up(&mem->state_sem);
+	return ret;
+}
+
+static ssize_t
+store_mem_state(struct sys_device *dev, const char *buf, size_t count)
+{
+	struct memory_block *mem;
+	unsigned int phys_section_nr;
+	int ret = -EINVAL;
+
+	mem = container_of(dev, struct memory_block, sysdev);
+	phys_section_nr = mem->phys_index;
+
+	if (!valid_section_nr(phys_section_nr))
+		goto out;
+
+	if (!strncmp(buf, "online", min((int)count, 6)))
+		ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
+	else if(!strncmp(buf, "offline", min((int)count, 7)))
+		ret = memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
+out:
+	if (ret)
+		return ret;
+	return count;
+}
+
+/*
+ * phys_device is a bad name for this.  What I really want
+ * is a way to differentiate between memory ranges that
+ * are part of physical devices that constitute
+ * a complete removable unit or fru.
+ * i.e. do these ranges belong to the same physical device,
+ * s.t. if I offline all of these sections I can then
+ * remove the physical device?
+ */
+static ssize_t show_phys_device(struct sys_device *dev, char *buf)
+{
+	struct memory_block *mem =
+		container_of(dev, struct memory_block, sysdev);
+	return sprintf(buf, "%d\n", mem->phys_device);
+}
+
+static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
+static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
+static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
+
+#define mem_create_simple_file(mem, attr_name)	\
+	sysdev_create_file(&mem->sysdev, &attr_##attr_name)
+#define mem_remove_simple_file(mem, attr_name)	\
+	sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
+
+/*
+ * Block size attribute stuff
+ */
+static ssize_t
+print_block_size(struct class *class, char *buf)
+{
+	return sprintf(buf, "%lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
+}
+
+static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
+
+static int block_size_init(void)
+{
+	sysfs_create_file(&memory_sysdev_class.kset.kobj,
+		&class_attr_block_size_bytes.attr);
+	return 0;
+}
+
+/*
+ * Some architectures will have custom drivers to do this, and
+ * will not need to do it from userspace.  The fake hot-add code
+ * as well as ppc64 will do all of their discovery in userspace
+ * and will require this interface.
+ */
+#ifdef CONFIG_ARCH_MEMORY_PROBE
+static ssize_t
+memory_probe_store(struct class *class, const char __user *buf, size_t count)
+{
+	u64 phys_addr;
+	int ret;
+
+	phys_addr = simple_strtoull(buf, NULL, 0);
+
+	ret = add_memory(phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
+
+	if (ret)
+		count = ret;
+
+	return count;
+}
+static CLASS_ATTR(probe, 0700, NULL, memory_probe_store);
+
+static int memory_probe_init(void)
+{
+	sysfs_create_file(&memory_sysdev_class.kset.kobj,
+		&class_attr_probe.attr);
+	return 0;
+}
+#else
+#define memory_probe_init(...)	do {} while (0)
+#endif
+
+/*
+ * Note that phys_device is optional.  It is here to allow for
+ * differentiation between which *physical* devices each
+ * section belongs to...
+ */
+
+static int add_memory_block(unsigned long node_id, struct mem_section *section,
+		     unsigned long state, int phys_device)
+{
+	struct memory_block *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+	int ret = 0;
+
+	if (!mem)
+		return -ENOMEM;
+
+	mem->phys_index = __section_nr(section);
+	mem->state = state;
+	init_MUTEX(&mem->state_sem);
+	mem->phys_device = phys_device;
+
+	ret = register_memory(mem, section, NULL);
+	if (!ret)
+		ret = mem_create_simple_file(mem, phys_index);
+	if (!ret)
+		ret = mem_create_simple_file(mem, state);
+	if (!ret)
+		ret = mem_create_simple_file(mem, phys_device);
+
+	return ret;
+}
+
+/*
+ * For now, we have a linear search to go find the appropriate
+ * memory_block corresponding to a particular phys_index. If
+ * this gets to be a real problem, we can always use a radix
+ * tree or something here.
+ *
+ * This could be made generic for all sysdev classes.
+ */
+static struct memory_block *find_memory_block(struct mem_section *section)
+{
+	struct kobject *kobj;
+	struct sys_device *sysdev;
+	struct memory_block *mem;
+	char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
+
+	/*
+	 * This only works because we know that section == sysdev->id
+	 * slightly redundant with sysdev_register()
+	 */
+	sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
+
+	kobj = kset_find_obj(&memory_sysdev_class.kset, name);
+	if (!kobj)
+		return NULL;
+
+	sysdev = container_of(kobj, struct sys_device, kobj);
+	mem = container_of(sysdev, struct memory_block, sysdev);
+
+	return mem;
+}
+
+int remove_memory_block(unsigned long node_id, struct mem_section *section,
+		int phys_device)
+{
+	struct memory_block *mem;
+
+	mem = find_memory_block(section);
+	mem_remove_simple_file(mem, phys_index);
+	mem_remove_simple_file(mem, state);
+	mem_remove_simple_file(mem, phys_device);
+	unregister_memory(mem, section, NULL);
+
+	return 0;
+}
+
+/*
+ * need an interface for the VM to add new memory regions,
+ * but without onlining it.
+ */
+int register_new_memory(struct mem_section *section)
+{
+	return add_memory_block(0, section, MEM_OFFLINE, 0);
+}
+
+int unregister_memory_section(struct mem_section *section)
+{
+	if (!valid_section(section))
+		return -EINVAL;
+
+	return remove_memory_block(0, section, 0);
+}
+
+/*
+ * Initialize the sysfs support for memory devices...
+ */
+int __init memory_dev_init(void)
+{
+	unsigned int i;
+	int ret;
+
+	memory_sysdev_class.kset.hotplug_ops = &memory_hotplug_ops;
+	ret = sysdev_class_register(&memory_sysdev_class);
+
+	/*
+	 * Create entries for memory sections that were found
+	 * during boot and have been initialized
+	 */
+	for (i = 0; i < NR_MEM_SECTIONS; i++) {
+		if (!valid_section_nr(i))
+			continue;
+		add_memory_block(0, __nr_to_section(i), MEM_ONLINE, 0);
+	}
+
+	memory_probe_init();
+	block_size_init();
+
+	return ret;
+}
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 28c1a628621f..cf6631056683 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -15,7 +15,7 @@
 #include <linux/crypto.h>
 #include <linux/workqueue.h>
 #include <asm/atomic.h>
-#include <asm/scatterlist.h>
+#include <linux/scatterlist.h>
 #include <asm/page.h>
 
 #include "dm.h"
@@ -164,9 +164,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
 		return -ENOMEM;
 	}
 
-	sg.page = virt_to_page(cc->key);
-	sg.offset = offset_in_page(cc->key);
-	sg.length = cc->key_size;
+	sg_set_buf(&sg, cc->key, cc->key_size);
 	crypto_digest_digest(hash_tfm, &sg, 1, salt);
 	crypto_free_tfm(hash_tfm);
 
@@ -207,14 +205,12 @@ static void crypt_iv_essiv_dtr(struct crypt_config *cc)
 
 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
 {
-	struct scatterlist sg = { NULL, };
+	struct scatterlist sg;
 
 	memset(iv, 0, cc->iv_size);
 	*(u64 *)iv = cpu_to_le64(sector);
 
-	sg.page = virt_to_page(iv);
-	sg.offset = offset_in_page(iv);
-	sg.length = cc->iv_size;
+	sg_set_buf(&sg, iv, cc->iv_size);
 	crypto_cipher_encrypt((struct crypto_tfm *)cc->iv_gen_private,
 	                      &sg, &sg, cc->iv_size);
 
diff --git a/drivers/net/wireless/airo.c b/drivers/net/wireless/airo.c
index 4c11699bad91..750c0167539c 100644
--- a/drivers/net/wireless/airo.c
+++ b/drivers/net/wireless/airo.c
@@ -35,6 +35,7 @@
 #include <linux/interrupt.h>
 #include <linux/in.h>
 #include <linux/bitops.h>
+#include <linux/scatterlist.h>
 #include <asm/io.h>
 #include <asm/system.h>
 
@@ -1590,11 +1591,9 @@ static void emmh32_setseed(emmh32_context *context, u8 *pkey, int keylen, struct
 		aes_counter[12] = (u8)(counter >> 24);
 		counter++;
 		memcpy (plain, aes_counter, 16);
-		sg[0].page = virt_to_page(plain);
-		sg[0].offset = ((long) plain & ~PAGE_MASK);
-		sg[0].length = 16;
+		sg_set_buf(sg, plain, 16);
 		crypto_cipher_encrypt(tfm, sg, sg, 16);
-		cipher = kmap(sg[0].page) + sg[0].offset;
+		cipher = kmap(sg->page) + sg->offset;
 		for (j=0; (j<16) && (i< (sizeof(context->coeff)/sizeof(context->coeff[0]))); ) {
 			context->coeff[i++] = ntohl(*(u32 *)&cipher[j]);
 			j += 4;
diff --git a/drivers/scsi/arm/scsi.h b/drivers/scsi/arm/scsi.h
index 48e1c4d9738b..19937640e2e7 100644
--- a/drivers/scsi/arm/scsi.h
+++ b/drivers/scsi/arm/scsi.h
@@ -10,6 +10,8 @@
  *  Commonly used scsi driver functions.
  */
 
+#include <linux/scatterlist.h>
+
 #define BELT_AND_BRACES
 
 /*
@@ -22,9 +24,7 @@ static inline int copy_SCp_to_sg(struct scatterlist *sg, Scsi_Pointer *SCp, int
 
 	BUG_ON(bufs + 1 > max);
 
-	sg->page   = virt_to_page(SCp->ptr);
-	sg->offset = offset_in_page(SCp->ptr);
-	sg->length = SCp->this_residual;
+	sg_set_buf(sg, SCp->ptr, SCp->this_residual);
 
 	if (bufs)
 		memcpy(sg + 1, SCp->buffer + 1,
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index d2f71a2331bb..771bc7d376bc 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -49,6 +49,7 @@
 #include <linux/suspend.h>
 #include <linux/workqueue.h>
 #include <linux/jiffies.h>
+#include <linux/scatterlist.h>
 #include <scsi/scsi.h>
 #include "scsi.h"
 #include "scsi_priv.h"
@@ -2554,19 +2555,12 @@ void ata_qc_prep(struct ata_queued_cmd *qc)
 
 void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)
 {
-	struct scatterlist *sg;
-
 	qc->flags |= ATA_QCFLAG_SINGLE;
 
-	memset(&qc->sgent, 0, sizeof(qc->sgent));
 	qc->sg = &qc->sgent;
 	qc->n_elem = 1;
 	qc->buf_virt = buf;
-
-	sg = qc->sg;
-	sg->page = virt_to_page(buf);
-	sg->offset = (unsigned long) buf & ~PAGE_MASK;
-	sg->length = buflen;
+	sg_init_one(qc->sg, buf, buflen);
 }
 
 /**
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 861e51375d70..d86d5c26061d 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -49,6 +49,7 @@ static int sg_version_num = 30533;	/* 2 digits for each component */
 #include <linux/seq_file.h>
 #include <linux/blkdev.h>
 #include <linux/delay.h>
+#include <linux/scatterlist.h>
 
 #include "scsi.h"
 #include <scsi/scsi_dbg.h>
@@ -1886,13 +1887,17 @@ st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
 	int i;
 
 	for (i=0; i < nr_pages; i++) {
-		if (dirtied && !PageReserved(sgl[i].page))
-			SetPageDirty(sgl[i].page);
-		/* unlock_page(sgl[i].page); */
+		struct page *page = sgl[i].page;
+
+		/* XXX: just for debug. Remove when PageReserved is removed */
+		BUG_ON(PageReserved(page));
+		if (dirtied)
+			SetPageDirty(page);
+		/* unlock_page(page); */
 		/* FIXME: cache flush missing for rw==READ
 		 * FIXME: call the correct reference counting function
 		 */
-		page_cache_release(sgl[i].page);
+		page_cache_release(page);
 	}
 
 	return 0;
@@ -1992,9 +1997,7 @@ sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
 				if (!p)
 					break;
 			}
-			sclp->page = virt_to_page(p);
-			sclp->offset = offset_in_page(p);
-			sclp->length = ret_sz;
+			sg_set_buf(sclp, p, ret_sz);
 
 			SCSI_LOG_TIMEOUT(5, printk("sg_build_build: k=%d, a=0x%p, len=%d\n",
 					  k, sg_scatg2virt(sclp), ret_sz));
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 5eb54d8019b4..da9766283bd7 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -4526,12 +4526,16 @@ static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_p
 	int i;
 
 	for (i=0; i < nr_pages; i++) {
-		if (dirtied && !PageReserved(sgl[i].page))
-			SetPageDirty(sgl[i].page);
+		struct page *page = sgl[i].page;
+
+		/* XXX: just for debug. Remove when PageReserved is removed */
+		BUG_ON(PageReserved(page));
+		if (dirtied)
+			SetPageDirty(page);
 		/* FIXME: cache flush missing for rw==READ
 		 * FIXME: call the correct reference counting function
 		 */
-		page_cache_release(sgl[i].page);
+		page_cache_release(page);
 	}
 
 	return 0;
diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
index 90a96257d6ce..2997f558159b 100644
--- a/drivers/usb/misc/usbtest.c
+++ b/drivers/usb/misc/usbtest.c
@@ -9,7 +9,7 @@
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
-#include <asm/scatterlist.h>
+#include <linux/scatterlist.h>
 
 #include <linux/usb.h>
 
@@ -381,7 +381,6 @@ alloc_sglist (int nents, int max, int vary)
 	sg = kmalloc (nents * sizeof *sg, SLAB_KERNEL);
 	if (!sg)
 		return NULL;
-	memset (sg, 0, nents * sizeof *sg);
 
 	for (i = 0; i < nents; i++) {
 		char		*buf;
@@ -394,9 +393,7 @@ alloc_sglist (int nents, int max, int vary)
 		memset (buf, 0, size);
 
 		/* kmalloc pages are always physically contiguous! */
-		sg [i].page = virt_to_page (buf);
-		sg [i].offset = offset_in_page (buf);
-		sg [i].length = size;
+		sg_init_one(&sg[i], buf, size);
 
 		if (vary) {
 			size += vary;