diff options
Diffstat (limited to 'drivers/xen/tmem.c')
| -rw-r--r-- | drivers/xen/tmem.c | 419 |
1 files changed, 0 insertions, 419 deletions
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c deleted file mode 100644 index 64d7479ad5ad..000000000000 --- a/drivers/xen/tmem.c +++ /dev/null @@ -1,419 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Xen implementation for transcendent memory (tmem) - * - * Copyright (C) 2009-2011 Oracle Corp. All rights reserved. - * Author: Dan Magenheimer - */ - -#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/types.h> -#include <linux/init.h> -#include <linux/pagemap.h> -#include <linux/cleancache.h> -#include <linux/frontswap.h> - -#include <xen/xen.h> -#include <xen/interface/xen.h> -#include <xen/page.h> -#include <asm/xen/hypercall.h> -#include <asm/xen/hypervisor.h> -#include <xen/tmem.h> - -#ifndef CONFIG_XEN_TMEM_MODULE -bool __read_mostly tmem_enabled = false; - -static int __init enable_tmem(char *s) -{ - tmem_enabled = true; - return 1; -} -__setup("tmem", enable_tmem); -#endif - -#ifdef CONFIG_CLEANCACHE -static bool cleancache __read_mostly = true; -module_param(cleancache, bool, S_IRUGO); -static bool selfballooning __read_mostly = true; -module_param(selfballooning, bool, S_IRUGO); -#endif /* CONFIG_CLEANCACHE */ - -#ifdef CONFIG_FRONTSWAP -static bool frontswap __read_mostly = true; -module_param(frontswap, bool, S_IRUGO); -#else /* CONFIG_FRONTSWAP */ -#define frontswap (0) -#endif /* CONFIG_FRONTSWAP */ - -#ifdef CONFIG_XEN_SELFBALLOONING -static bool selfshrinking __read_mostly = true; -module_param(selfshrinking, bool, S_IRUGO); -#endif /* CONFIG_XEN_SELFBALLOONING */ - -#define TMEM_CONTROL 0 -#define TMEM_NEW_POOL 1 -#define TMEM_DESTROY_POOL 2 -#define TMEM_NEW_PAGE 3 -#define TMEM_PUT_PAGE 4 -#define TMEM_GET_PAGE 5 -#define TMEM_FLUSH_PAGE 6 -#define TMEM_FLUSH_OBJECT 7 -#define TMEM_READ 8 -#define TMEM_WRITE 9 -#define TMEM_XCHG 10 - -/* Bits for HYPERVISOR_tmem_op(TMEM_NEW_POOL) */ -#define TMEM_POOL_PERSIST 1 -#define TMEM_POOL_SHARED 2 -#define TMEM_POOL_PAGESIZE_SHIFT 4 -#define TMEM_VERSION_SHIFT 24 - - -struct tmem_pool_uuid { - u64 uuid_lo; - u64 uuid_hi; -}; - -struct tmem_oid { - u64 oid[3]; -}; - -#define TMEM_POOL_PRIVATE_UUID { 0, 0 } - -/* flags for tmem_ops.new_pool */ -#define TMEM_POOL_PERSIST 1 -#define TMEM_POOL_SHARED 2 - -/* xen tmem foundation ops/hypercalls */ - -static inline int xen_tmem_op(u32 tmem_cmd, u32 tmem_pool, struct tmem_oid oid, - u32 index, unsigned long gmfn, u32 tmem_offset, u32 pfn_offset, u32 len) -{ - struct tmem_op op; - int rc = 0; - - op.cmd = tmem_cmd; - op.pool_id = tmem_pool; - op.u.gen.oid[0] = oid.oid[0]; - op.u.gen.oid[1] = oid.oid[1]; - op.u.gen.oid[2] = oid.oid[2]; - op.u.gen.index = index; - op.u.gen.tmem_offset = tmem_offset; - op.u.gen.pfn_offset = pfn_offset; - op.u.gen.len = len; - set_xen_guest_handle(op.u.gen.gmfn, (void *)gmfn); - rc = HYPERVISOR_tmem_op(&op); - return rc; -} - -static int xen_tmem_new_pool(struct tmem_pool_uuid uuid, - u32 flags, unsigned long pagesize) -{ - struct tmem_op op; - int rc = 0, pageshift; - - for (pageshift = 0; pagesize != 1; pageshift++) - pagesize >>= 1; - flags |= (pageshift - 12) << TMEM_POOL_PAGESIZE_SHIFT; - flags |= TMEM_SPEC_VERSION << TMEM_VERSION_SHIFT; - op.cmd = TMEM_NEW_POOL; - op.u.new.uuid[0] = uuid.uuid_lo; - op.u.new.uuid[1] = uuid.uuid_hi; - op.u.new.flags = flags; - rc = HYPERVISOR_tmem_op(&op); - return rc; -} - -/* xen generic tmem ops */ - -static int xen_tmem_put_page(u32 pool_id, struct tmem_oid oid, - u32 index, struct page *page) -{ - return xen_tmem_op(TMEM_PUT_PAGE, pool_id, oid, index, - xen_page_to_gfn(page), 0, 0, 0); -} - -static int xen_tmem_get_page(u32 pool_id, struct tmem_oid oid, - u32 index, struct page *page) -{ - return xen_tmem_op(TMEM_GET_PAGE, pool_id, oid, index, - xen_page_to_gfn(page), 0, 0, 0); -} - -static int xen_tmem_flush_page(u32 pool_id, struct tmem_oid oid, u32 index) -{ - return xen_tmem_op(TMEM_FLUSH_PAGE, pool_id, oid, index, - 0, 0, 0, 0); -} - -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); -} - - -#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, - pgoff_t index, struct page *page) -{ - u32 ind = (u32) index; - struct tmem_oid oid = *(struct tmem_oid *)&key; - - if (pool < 0) - return; - if (ind != index) - return; - mb(); /* ensure page is quiescent; tmem may address it with an alias */ - (void)xen_tmem_put_page((u32)pool, oid, ind, page); -} - -static int tmem_cleancache_get_page(int pool, struct cleancache_filekey key, - pgoff_t index, struct page *page) -{ - u32 ind = (u32) index; - struct tmem_oid oid = *(struct tmem_oid *)&key; - int ret; - - /* translate return values to linux semantics */ - if (pool < 0) - return -1; - if (ind != index) - return -1; - ret = xen_tmem_get_page((u32)pool, oid, ind, page); - if (ret == 1) - return 0; - else - return -1; -} - -static void tmem_cleancache_flush_page(int pool, struct cleancache_filekey key, - pgoff_t index) -{ - u32 ind = (u32) index; - struct tmem_oid oid = *(struct tmem_oid *)&key; - - if (pool < 0) - return; - if (ind != index) - return; - (void)xen_tmem_flush_page((u32)pool, oid, ind); -} - -static void tmem_cleancache_flush_inode(int pool, struct cleancache_filekey key) -{ - struct tmem_oid oid = *(struct tmem_oid *)&key; - - if (pool < 0) - return; - (void)xen_tmem_flush_object((u32)pool, oid); -} - -static void tmem_cleancache_flush_fs(int pool) -{ - if (pool < 0) - return; - (void)xen_tmem_destroy_pool((u32)pool); -} - -static int tmem_cleancache_init_fs(size_t pagesize) -{ - struct tmem_pool_uuid uuid_private = TMEM_POOL_PRIVATE_UUID; - - return xen_tmem_new_pool(uuid_private, 0, pagesize); -} - -static int tmem_cleancache_init_shared_fs(uuid_t *uuid, size_t pagesize) -{ - struct tmem_pool_uuid shared_uuid; - - shared_uuid.uuid_lo = *(u64 *)&uuid->b[0]; - shared_uuid.uuid_hi = *(u64 *)&uuid->b[8]; - return xen_tmem_new_pool(shared_uuid, TMEM_POOL_SHARED, pagesize); -} - -static const struct cleancache_ops tmem_cleancache_ops = { - .put_page = tmem_cleancache_put_page, - .get_page = tmem_cleancache_get_page, - .invalidate_page = tmem_cleancache_flush_page, - .invalidate_inode = tmem_cleancache_flush_inode, - .invalidate_fs = tmem_cleancache_flush_fs, - .init_shared_fs = tmem_cleancache_init_shared_fs, - .init_fs = tmem_cleancache_init_fs -}; -#endif - -#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 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_store(unsigned type, pgoff_t offset, - struct page *page) -{ - u64 ind64 = (u64)offset; - u32 ind = (u32)offset; - int pool = tmem_frontswap_poolid; - int ret; - - /* THP isn't supported */ - if (PageTransHuge(page)) - return -1; - - 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), page); - /* 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_load(unsigned type, pgoff_t offset, - struct page *page) -{ - u64 ind64 = (u64)offset; - u32 ind = (u32)offset; - 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), page); - /* 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 struct frontswap_ops tmem_frontswap_ops = { - .store = tmem_frontswap_store, - .load = tmem_frontswap_load, - .invalidate_page = tmem_frontswap_flush_page, - .invalidate_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 && frontswap) { - char *s = ""; - - tmem_frontswap_poolid = -1; - frontswap_register_ops(&tmem_frontswap_ops); - pr_info("frontswap enabled, RAM provided by Xen Transcendent Memory%s\n", - s); - } -#endif -#ifdef CONFIG_CLEANCACHE - BUILD_BUG_ON(sizeof(struct cleancache_filekey) != sizeof(struct tmem_oid)); - if (tmem_enabled && cleancache) { - int err; - - err = cleancache_register_ops(&tmem_cleancache_ops); - if (err) - pr_warn("xen-tmem: failed to enable cleancache: %d\n", - err); - else - pr_info("cleancache enabled, RAM provided by " - "Xen Transcendent Memory\n"); - } -#endif -#ifdef CONFIG_XEN_SELFBALLOONING - /* - * There is no point of driving pages to the swap system if they - * aren't going anywhere in tmem universe. - */ - if (!frontswap) { - selfshrinking = false; - selfballooning = false; - } - xen_selfballoon_init(selfballooning, selfshrinking); -#endif - return 0; -} - -module_init(xen_tmem_init) -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Dan Magenheimer <dan.magenheimer@oracle.com>"); -MODULE_DESCRIPTION("Shim to Xen transcendent memory"); |