Merge branch 'stable/frontswap-tmemonly' of... (03dc6107) · Commits · EulixOS / Software / Kernel

drivers/xen/Kconfig

+7 −0

Original line number	Diff line number	Diff line
		@@ -105,4 +105,11 @@ config SWIOTLB_XEN
		depends on PCI
		select SWIOTLB

		config XEN_TMEM
		bool
		default y if (CLEANCACHE \|\| FRONTSWAP)
		help
		Shim to interface in-kernel Transcendent Memory hooks
		(e.g. cleancache and frontswap) to Xen tmem hypercalls.

		endmenu

drivers/xen/Makefile

+1 −1

Original line number	Diff line number	Diff line
		obj-y += grant-table.o features.o events.o manage.o balloon.o
		obj-y += xenbus/
		obj-y += tmem.o

		nostackp := $(call cc-option, -fno-stack-protector)
		CFLAGS_features.o := $(nostackp)
		@@ -15,6 +14,7 @@ obj-$(CONFIG_XEN_GRANT_DEV_ALLOC) += xen-gntalloc.o
		obj-$(CONFIG_XENFS) += xenfs/
		obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o
		obj-$(CONFIG_XEN_PLATFORM_PCI) += xen-platform-pci.o
		obj-$(CONFIG_XEN_TMEM) += tmem.o
		obj-$(CONFIG_SWIOTLB_XEN) += swiotlb-xen.o
		obj-$(CONFIG_XEN_DOM0) += pci.o

drivers/xen/tmem.c

+158 −12

Original line number	Diff line number	Diff line
		/*
		* Xen implementation for transcendent memory (tmem)
		*
		* Copyright (C) 2009-2010 Oracle Corp. All rights reserved.
		* Copyright (C) 2009-2011 Oracle Corp. All rights reserved.
		* Author: Dan Magenheimer
		*/

		@@ -9,8 +9,14 @@
		#include <linux/types.h>
		#include <linux/init.h>
		#include <linux/pagemap.h>
		#include <linux/module.h>
		#include <linux/cleancache.h>

		/* temporary ifdef until include/linux/frontswap.h is upstream */
		#ifdef CONFIG_FRONTSWAP
		#include <linux/frontswap.h>
		#endif

		#include <xen/xen.h>
		#include <xen/interface/xen.h>
		#include <asm/xen/hypercall.h>
		@@ -122,14 +128,8 @@ static int xen_tmem_flush_object(u32 pool_id, struct tmem_oid oid)
		return xen_tmem_op(TMEM_FLUSH_OBJECT, pool_id, oid, 0, 0, 0, 0, 0);
		}

		static int xen_tmem_destroy_pool(u32 pool_id)
		{
		struct tmem_oid oid = { { 0 } };

		return xen_tmem_op(TMEM_DESTROY_POOL, pool_id, oid, 0, 0, 0, 0, 0);
		}

		int tmem_enabled;
		int tmem_enabled __read_mostly;
		EXPORT_SYMBOL(tmem_enabled);

		static int __init enable_tmem(char *s)
		{
		@@ -139,6 +139,14 @@ static int __init enable_tmem(char *s)

		__setup("tmem", enable_tmem);

		#ifdef CONFIG_CLEANCACHE
		static int xen_tmem_destroy_pool(u32 pool_id)
		{
		struct tmem_oid oid = { { 0 } };

		return xen_tmem_op(TMEM_DESTROY_POOL, pool_id, oid, 0, 0, 0, 0, 0);
		}

		/* cleancache ops */

		static void tmem_cleancache_put_page(int pool, struct cleancache_filekey key,
		@@ -240,18 +248,156 @@ static struct cleancache_ops tmem_cleancache_ops = {
		.init_shared_fs = tmem_cleancache_init_shared_fs,
		.init_fs = tmem_cleancache_init_fs
		};
		#endif

		static int __init xen_tmem_init(void)
		#ifdef CONFIG_FRONTSWAP
		/* frontswap tmem operations */

		/* a single tmem poolid is used for all frontswap "types" (swapfiles) */
		static int tmem_frontswap_poolid;

		/*
		* Swizzling increases objects per swaptype, increasing tmem concurrency
		* for heavy swaploads. Later, larger nr_cpus -> larger SWIZ_BITS
		*/
		#define SWIZ_BITS 4
		#define SWIZ_MASK ((1 << SWIZ_BITS) - 1)
		#define _oswiz(_type, _ind) ((_type << SWIZ_BITS) \| (_ind & SWIZ_MASK))
		#define iswiz(_ind) (_ind >> SWIZ_BITS)

		static inline struct tmem_oid oswiz(unsigned type, u32 ind)
		{
		struct cleancache_ops old_ops;
		struct tmem_oid oid = { .oid = { 0 } };
		oid.oid[0] = _oswiz(type, ind);
		return oid;
		}

		/* returns 0 if the page was successfully put into frontswap, -1 if not */
		static int tmem_frontswap_put_page(unsigned type, pgoff_t offset,
		struct page *page)
		{
		u64 ind64 = (u64)offset;
		u32 ind = (u32)offset;
		unsigned long pfn = page_to_pfn(page);
		int pool = tmem_frontswap_poolid;
		int ret;

		if (pool < 0)
		return -1;
		if (ind64 != ind)
		return -1;
		mb(); /* ensure page is quiescent; tmem may address it with an alias */
		ret = xen_tmem_put_page(pool, oswiz(type, ind), iswiz(ind), pfn);
		/* translate Xen tmem return values to linux semantics */
		if (ret == 1)
		return 0;
		else
		return -1;
		}

		/*
		* returns 0 if the page was successfully gotten from frontswap, -1 if
		* was not present (should never happen!)
		*/
		static int tmem_frontswap_get_page(unsigned type, pgoff_t offset,
		struct page *page)
		{
		u64 ind64 = (u64)offset;
		u32 ind = (u32)offset;
		unsigned long pfn = page_to_pfn(page);
		int pool = tmem_frontswap_poolid;
		int ret;

		if (pool < 0)
		return -1;
		if (ind64 != ind)
		return -1;
		ret = xen_tmem_get_page(pool, oswiz(type, ind), iswiz(ind), pfn);
		/* translate Xen tmem return values to linux semantics */
		if (ret == 1)
		return 0;
		else
		return -1;
		}

		/* flush a single page from frontswap */
		static void tmem_frontswap_flush_page(unsigned type, pgoff_t offset)
		{
		u64 ind64 = (u64)offset;
		u32 ind = (u32)offset;
		int pool = tmem_frontswap_poolid;

		if (pool < 0)
		return;
		if (ind64 != ind)
		return;
		(void) xen_tmem_flush_page(pool, oswiz(type, ind), iswiz(ind));
		}

		/* flush all pages from the passed swaptype */
		static void tmem_frontswap_flush_area(unsigned type)
		{
		int pool = tmem_frontswap_poolid;
		int ind;

		if (pool < 0)
		return;
		for (ind = SWIZ_MASK; ind >= 0; ind--)
		(void)xen_tmem_flush_object(pool, oswiz(type, ind));
		}

		static void tmem_frontswap_init(unsigned ignored)
		{
		struct tmem_pool_uuid private = TMEM_POOL_PRIVATE_UUID;

		/* a single tmem poolid is used for all frontswap "types" (swapfiles) */
		if (tmem_frontswap_poolid < 0)
		tmem_frontswap_poolid =
		xen_tmem_new_pool(private, TMEM_POOL_PERSIST, PAGE_SIZE);
		}

		static int __initdata use_frontswap = 1;

		static int __init no_frontswap(char *s)
		{
		use_frontswap = 0;
		return 1;
		}

		__setup("nofrontswap", no_frontswap);

		static struct frontswap_ops tmem_frontswap_ops = {
		.put_page = tmem_frontswap_put_page,
		.get_page = tmem_frontswap_get_page,
		.flush_page = tmem_frontswap_flush_page,
		.flush_area = tmem_frontswap_flush_area,
		.init = tmem_frontswap_init
		};
		#endif

		static int __init xen_tmem_init(void)
		{
		if (!xen_domain())
		return 0;
		#ifdef CONFIG_FRONTSWAP
		if (tmem_enabled && use_frontswap) {
		char *s = "";
		struct frontswap_ops old_ops =
		frontswap_register_ops(&tmem_frontswap_ops);

		tmem_frontswap_poolid = -1;
		if (old_ops.init != NULL)
		s = " (WARNING: frontswap_ops overridden)";
		printk(KERN_INFO "frontswap enabled, RAM provided by "
		"Xen Transcendent Memory\n");
		}
		#endif
		#ifdef CONFIG_CLEANCACHE
		BUG_ON(sizeof(struct cleancache_filekey) != sizeof(struct tmem_oid));
		if (tmem_enabled && use_cleancache) {
		char *s = "";
		old_ops = cleancache_register_ops(&tmem_cleancache_ops);
		struct cleancache_ops old_ops =
		cleancache_register_ops(&tmem_cleancache_ops);
		if (old_ops.init_fs != NULL)
		s = " (WARNING: cleancache_ops overridden)";
		printk(KERN_INFO "cleancache enabled, RAM provided by "