/************************************************************************** * * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE * USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ /* * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> */ #include <linux/sched.h> #include <linux/highmem.h> #include <linux/pagemap.h> #include <linux/file.h> #include <linux/swap.h> #include <linux/slab.h> #include "drm_cache.h" #include "drm_mem_util.h" #include "ttm/ttm_module.h" #include "ttm/ttm_bo_driver.h" #include "ttm/ttm_placement.h" #include "ttm/ttm_page_alloc.h" static int ttm_tt_swapin(struct ttm_tt *ttm); /** * Allocates storage for pointers to the pages that back the ttm. */ static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm) { ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(*ttm->pages)); ttm->dma_address = drm_calloc_large(ttm->num_pages, sizeof(*ttm->dma_address)); } static void ttm_tt_free_page_directory(struct ttm_tt *ttm) { drm_free_large(ttm->pages); ttm->pages = NULL; drm_free_large(ttm->dma_address); ttm->dma_address = NULL; } static void ttm_tt_free_user_pages(struct ttm_tt *ttm) { int write; int dirty; struct page *page; int i; struct ttm_backend *be = ttm->be; BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER)); write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0); dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0); if (be) be->func->clear(be); for (i = 0; i < ttm->num_pages; ++i) { page = ttm->pages[i]; if (page == NULL) continue; if (page == ttm->dummy_read_page) { BUG_ON(write); continue; } if (write && dirty && !PageReserved(page)) set_page_dirty_lock(page); ttm->pages[i] = NULL; ttm_mem_global_free(ttm->glob->mem_glob, PAGE_SIZE); put_page(page); } ttm->state = tt_unpopulated; ttm->first_himem_page = ttm->num_pages; ttm->last_lomem_page = -1; } static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index) { struct page *p; struct list_head h; struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; int ret; while (NULL == (p = ttm->pages[index])) { INIT_LIST_HEAD(&h); ret = ttm_get_pages(&h, ttm->page_flags, ttm->caching_state, 1, &ttm->dma_address[index]); if (ret != 0) return NULL; p = list_first_entry(&h, struct page, lru); ret = ttm_mem_global_alloc_page(mem_glob, p, false, false); if (unlikely(ret != 0)) goto out_err; if (PageHighMem(p)) ttm->pages[--ttm->first_himem_page] = p; else ttm->pages[++ttm->last_lomem_page] = p; } return p; out_err: put_page(p); return NULL; } struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index) { int ret; if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { ret = ttm_tt_swapin(ttm); if (unlikely(ret != 0)) return NULL; } return __ttm_tt_get_page(ttm, index); } int ttm_tt_populate(struct ttm_tt *ttm) { struct page *page; unsigned long i; struct ttm_backend *be; int ret; if (ttm->state != tt_unpopulated) return 0; if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { ret = ttm_tt_swapin(ttm); if (unlikely(ret != 0)) return ret; } be = ttm->be; for (i = 0; i < ttm->num_pages; ++i) { page = __ttm_tt_get_page(ttm, i); if (!page) return -ENOMEM; } be->func->populate(be, ttm->num_pages, ttm->pages, ttm->dummy_read_page, ttm->dma_address); ttm->state = tt_unbound; return 0; } EXPORT_SYMBOL(ttm_tt_populate); #ifdef CONFIG_X86 static inline int ttm_tt_set_page_caching(struct page *p, enum ttm_caching_state c_old, enum ttm_caching_state c_new) { int ret = 0; if (PageHighMem(p)) return 0; if (c_old != tt_cached) { /* p isn't in the default caching state, set it to * writeback first to free its current memtype. */ ret = set_pages_wb(p, 1); if (ret) return ret; } if (c_new == tt_wc) ret = set_memory_wc((unsigned long) page_address(p), 1); else if (c_new == tt_uncached) ret = set_pages_uc(p, 1); return ret; } #else /* CONFIG_X86 */ static inline int ttm_tt_set_page_caching(struct page *p, enum ttm_caching_state c_old, enum ttm_caching_state c_new) { return 0; } #endif /* CONFIG_X86 */ /* * Change caching policy for the linear kernel map * for range of pages in a ttm. */ static int ttm_tt_set_caching(struct ttm_tt *ttm, enum ttm_caching_state c_state) { int i, j; struct page *cur_page; int ret; if (ttm->caching_state == c_state) return 0; if (ttm->state == tt_unpopulated) { /* Change caching but don't populate */ ttm->caching_state = c_state; return 0; } if (ttm->caching_state == tt_cached) drm_clflush_pages(ttm->pages, ttm->num_pages); for (i = 0; i < ttm->num_pages; ++i) { cur_page = ttm->pages[i]; if (likely(cur_page != NULL)) { ret = ttm_tt_set_page_caching(cur_page, ttm->caching_state, c_state); if (unlikely(ret != 0)) goto out_err; } } ttm->caching_state = c_state; return 0; out_err: for (j = 0; j < i; ++j) { cur_page = ttm->pages[j]; if (likely(cur_page != NULL)) { (void)ttm_tt_set_page_caching(cur_page, c_state, ttm->caching_state); } } return ret; } int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement) { enum ttm_caching_state state; if (placement & TTM_PL_FLAG_WC) state = tt_wc; else if (placement & TTM_PL_FLAG_UNCACHED) state = tt_uncached; else state = tt_cached; return ttm_tt_set_caching(ttm, state); } EXPORT_SYMBOL(ttm_tt_set_placement_caching); static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm) { int i; unsigned count = 0; struct list_head h; struct page *cur_page; struct ttm_backend *be = ttm->be; INIT_LIST_HEAD(&h); if (be) be->func->clear(be); for (i = 0; i < ttm->num_pages; ++i) { cur_page = ttm->pages[i]; ttm->pages[i] = NULL; if (cur_page) { if (page_count(cur_page) != 1) printk(KERN_ERR TTM_PFX "Erroneous page count. " "Leaking pages.\n"); ttm_mem_global_free_page(ttm->glob->mem_glob, cur_page); list_add(&cur_page->lru, &h); count++; } } ttm_put_pages(&h, count, ttm->page_flags, ttm->caching_state, ttm->dma_address); ttm->state = tt_unpopulated; ttm->first_himem_page = ttm->num_pages; ttm->last_lomem_page = -1; } void ttm_tt_destroy(struct ttm_tt *ttm) { struct ttm_backend *be; if (unlikely(ttm == NULL)) return; be = ttm->be; if (likely(be != NULL)) { be->func->destroy(be); ttm->be = NULL; } if (likely(ttm->pages != NULL)) { if (ttm->page_flags & TTM_PAGE_FLAG_USER) ttm_tt_free_user_pages(ttm); else ttm_tt_free_alloced_pages(ttm); ttm_tt_free_page_directory(ttm); } if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) && ttm->swap_storage) fput(ttm->swap_storage); kfree(ttm); } int ttm_tt_set_user(struct ttm_tt *ttm, struct task_struct *tsk, unsigned long start, unsigned long num_pages) { struct mm_struct *mm = tsk->mm; int ret; int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0; struct ttm_mem_global *mem_glob = ttm->glob->mem_glob; BUG_ON(num_pages != ttm->num_pages); BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0); /** * Account user pages as lowmem pages for now. */ ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE, false, false); if (unlikely(ret != 0)) return ret; down_read(&mm->mmap_sem); ret = get_user_pages(tsk, mm, start, num_pages, write, 0, ttm->pages, NULL); up_read(&mm->mmap_sem); if (ret != num_pages && write) { ttm_tt_free_user_pages(ttm); ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE); return -ENOMEM; } ttm->tsk = tsk; ttm->start = start; ttm->state = tt_unbound; return 0; } struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size, uint32_t page_flags, struct page *dummy_read_page) { struct ttm_bo_driver *bo_driver = bdev->driver; struct ttm_tt *ttm; if (!bo_driver) return NULL; ttm = kzalloc(sizeof(*ttm), GFP_KERNEL); if (!ttm) return NULL; ttm->glob = bdev->glob; ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; ttm->first_himem_page = ttm->num_pages; ttm->last_lomem_page = -1; ttm->caching_state = tt_cached; ttm->page_flags = page_flags; ttm->dummy_read_page = dummy_read_page; ttm_tt_alloc_page_directory(ttm); if (!ttm->pages) { ttm_tt_destroy(ttm); printk(KERN_ERR TTM_PFX "Failed allocating page table\n"); return NULL; } ttm->be = bo_driver->create_ttm_backend_entry(bdev); if (!ttm->be) { ttm_tt_destroy(ttm); printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n"); return NULL; } ttm->state = tt_unpopulated; return ttm; } void ttm_tt_unbind(struct ttm_tt *ttm) { int ret; struct ttm_backend *be = ttm->be; if (ttm->state == tt_bound) { ret = be->func->unbind(be); BUG_ON(ret); ttm->state = tt_unbound; } } int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem) { int ret = 0; struct ttm_backend *be; if (!ttm) return -EINVAL; if (ttm->state == tt_bound) return 0; be = ttm->be; ret = ttm_tt_populate(ttm); if (ret) return ret; ret = be->func->bind(be, bo_mem); if (unlikely(ret != 0)) return ret; ttm->state = tt_bound; if (ttm->page_flags & TTM_PAGE_FLAG_USER) ttm->page_flags |= TTM_PAGE_FLAG_USER_DIRTY; return 0; } EXPORT_SYMBOL(ttm_tt_bind); static int ttm_tt_swapin(struct ttm_tt *ttm) { struct address_space *swap_space; struct file *swap_storage; struct page *from_page; struct page *to_page; void *from_virtual; void *to_virtual; int i; int ret = -ENOMEM; if (ttm->page_flags & TTM_PAGE_FLAG_USER) { ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start, ttm->num_pages); if (unlikely(ret != 0)) return ret; ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; return 0; } swap_storage = ttm->swap_storage; BUG_ON(swap_storage == NULL); swap_space = swap_storage->f_path.dentry->d_inode->i_mapping; for (i = 0; i < ttm->num_pages; ++i) { from_page = read_mapping_page(swap_space, i, NULL); if (IS_ERR(from_page)) { ret = PTR_ERR(from_page); goto out_err; } to_page = __ttm_tt_get_page(ttm, i); if (unlikely(to_page == NULL)) goto out_err; preempt_disable(); from_virtual = kmap_atomic(from_page, KM_USER0); to_virtual = kmap_atomic(to_page, KM_USER1); memcpy(to_virtual, from_virtual, PAGE_SIZE); kunmap_atomic(to_virtual, KM_USER1); kunmap_atomic(from_virtual, KM_USER0); preempt_enable(); page_cache_release(from_page); } if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP)) fput(swap_storage); ttm->swap_storage = NULL; ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; return 0; out_err: ttm_tt_free_alloced_pages(ttm); return ret; } int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage) { struct address_space *swap_space; struct file *swap_storage; struct page *from_page; struct page *to_page; void *from_virtual; void *to_virtual; int i; int ret = -ENOMEM; BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated); BUG_ON(ttm->caching_state != tt_cached); /* * For user buffers, just unpin the pages, as there should be * vma references. */ if (ttm->page_flags & TTM_PAGE_FLAG_USER) { ttm_tt_free_user_pages(ttm); ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; ttm->swap_storage = NULL; return 0; } if (!persistent_swap_storage) { swap_storage = shmem_file_setup("ttm swap", ttm->num_pages << PAGE_SHIFT, 0); if (unlikely(IS_ERR(swap_storage))) { printk(KERN_ERR "Failed allocating swap storage.\n"); return PTR_ERR(swap_storage); } } else swap_storage = persistent_swap_storage; swap_space = swap_storage->f_path.dentry->d_inode->i_mapping; for (i = 0; i < ttm->num_pages; ++i) { from_page = ttm->pages[i]; if (unlikely(from_page == NULL)) continue; to_page = read_mapping_page(swap_space, i, NULL); if (unlikely(IS_ERR(to_page))) { ret = PTR_ERR(to_page); goto out_err; } preempt_disable(); from_virtual = kmap_atomic(from_page, KM_USER0); to_virtual = kmap_atomic(to_page, KM_USER1); memcpy(to_virtual, from_virtual, PAGE_SIZE); kunmap_atomic(to_virtual, KM_USER1); kunmap_atomic(from_virtual, KM_USER0); preempt_enable(); set_page_dirty(to_page); mark_page_accessed(to_page); page_cache_release(to_page); } ttm_tt_free_alloced_pages(ttm); ttm->swap_storage = swap_storage; ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; if (persistent_swap_storage) ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP; return 0; out_err: if (!persistent_swap_storage) fput(swap_storage); return ret; }