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mm/rmap.c
50.1 KB
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/* * mm/rmap.c - physical to virtual reverse mappings * * Copyright 2001, Rik van Riel <riel@conectiva.com.br> * Released under the General Public License (GPL). * * Simple, low overhead reverse mapping scheme. * Please try to keep this thing as modular as possible. * * Provides methods for unmapping each kind of mapped page: * the anon methods track anonymous pages, and * the file methods track pages belonging to an inode. * * Original design by Rik van Riel <riel@conectiva.com.br> 2001 * File methods by Dave McCracken <dmccr@us.ibm.com> 2003, 2004 * Anonymous methods by Andrea Arcangeli <andrea@suse.de> 2004 |
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* Contributions by Hugh Dickins 2003, 2004 |
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*/ /* * Lock ordering in mm: * |
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* inode->i_mutex (while writing or truncating, not reading or faulting) |
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* mm->mmap_sem * page->flags PG_locked (lock_page) |
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* mapping->i_mmap_mutex |
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* anon_vma->mutex |
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* mm->page_table_lock or pte_lock * zone->lru_lock (in mark_page_accessed, isolate_lru_page) * swap_lock (in swap_duplicate, swap_info_get) * mmlist_lock (in mmput, drain_mmlist and others) * mapping->private_lock (in __set_page_dirty_buffers) |
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* inode->i_lock (in set_page_dirty's __mark_inode_dirty) |
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* bdi.wb->list_lock (in set_page_dirty's __mark_inode_dirty) |
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* sb_lock (within inode_lock in fs/fs-writeback.c) * mapping->tree_lock (widely used, in set_page_dirty, * in arch-dependent flush_dcache_mmap_lock, |
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* within bdi.wb->list_lock in __sync_single_inode) |
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* |
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* anon_vma->mutex,mapping->i_mutex (memory_failure, collect_procs_anon) * ->tasklist_lock |
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* pte map lock |
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*/ #include <linux/mm.h> #include <linux/pagemap.h> #include <linux/swap.h> #include <linux/swapops.h> #include <linux/slab.h> #include <linux/init.h> |
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#include <linux/ksm.h> |
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#include <linux/rmap.h> #include <linux/rcupdate.h> |
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#include <linux/export.h> |
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#include <linux/memcontrol.h> |
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#include <linux/mmu_notifier.h> |
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#include <linux/migrate.h> |
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#include <linux/hugetlb.h> |
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#include <asm/tlbflush.h> |
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#include "internal.h" |
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static struct kmem_cache *anon_vma_cachep; |
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static struct kmem_cache *anon_vma_chain_cachep; |
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static inline struct anon_vma *anon_vma_alloc(void) { |
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struct anon_vma *anon_vma; anon_vma = kmem_cache_alloc(anon_vma_cachep, GFP_KERNEL); if (anon_vma) { atomic_set(&anon_vma->refcount, 1); /* * Initialise the anon_vma root to point to itself. If called * from fork, the root will be reset to the parents anon_vma. */ anon_vma->root = anon_vma; } return anon_vma; |
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} |
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static inline void anon_vma_free(struct anon_vma *anon_vma) |
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{ |
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VM_BUG_ON(atomic_read(&anon_vma->refcount)); |
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/* * Synchronize against page_lock_anon_vma() such that * we can safely hold the lock without the anon_vma getting * freed. * * Relies on the full mb implied by the atomic_dec_and_test() from * put_anon_vma() against the acquire barrier implied by * mutex_trylock() from page_lock_anon_vma(). This orders: * * page_lock_anon_vma() VS put_anon_vma() * mutex_trylock() atomic_dec_and_test() * LOCK MB * atomic_read() mutex_is_locked() * * LOCK should suffice since the actual taking of the lock must * happen _before_ what follows. */ if (mutex_is_locked(&anon_vma->root->mutex)) { anon_vma_lock(anon_vma); anon_vma_unlock(anon_vma); } |
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kmem_cache_free(anon_vma_cachep, anon_vma); } |
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|
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static inline struct anon_vma_chain *anon_vma_chain_alloc(gfp_t gfp) |
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{ |
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return kmem_cache_alloc(anon_vma_chain_cachep, gfp); |
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} |
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static void anon_vma_chain_free(struct anon_vma_chain *anon_vma_chain) |
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{ kmem_cache_free(anon_vma_chain_cachep, anon_vma_chain); } |
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/** * anon_vma_prepare - attach an anon_vma to a memory region * @vma: the memory region in question * * This makes sure the memory mapping described by 'vma' has * an 'anon_vma' attached to it, so that we can associate the * anonymous pages mapped into it with that anon_vma. * * The common case will be that we already have one, but if |
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* not we either need to find an adjacent mapping that we |
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* can re-use the anon_vma from (very common when the only * reason for splitting a vma has been mprotect()), or we * allocate a new one. * * Anon-vma allocations are very subtle, because we may have * optimistically looked up an anon_vma in page_lock_anon_vma() * and that may actually touch the spinlock even in the newly * allocated vma (it depends on RCU to make sure that the * anon_vma isn't actually destroyed). * * As a result, we need to do proper anon_vma locking even * for the new allocation. At the same time, we do not want * to do any locking for the common case of already having * an anon_vma. * * This must be called with the mmap_sem held for reading. */ |
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int anon_vma_prepare(struct vm_area_struct *vma) { struct anon_vma *anon_vma = vma->anon_vma; |
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struct anon_vma_chain *avc; |
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might_sleep(); if (unlikely(!anon_vma)) { struct mm_struct *mm = vma->vm_mm; |
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struct anon_vma *allocated; |
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|
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avc = anon_vma_chain_alloc(GFP_KERNEL); |
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if (!avc) goto out_enomem; |
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anon_vma = find_mergeable_anon_vma(vma); |
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allocated = NULL; if (!anon_vma) { |
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anon_vma = anon_vma_alloc(); if (unlikely(!anon_vma)) |
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goto out_enomem_free_avc; |
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allocated = anon_vma; |
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} |
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anon_vma_lock(anon_vma); |
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/* page_table_lock to protect against threads */ spin_lock(&mm->page_table_lock); if (likely(!vma->anon_vma)) { vma->anon_vma = anon_vma; |
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avc->anon_vma = anon_vma; avc->vma = vma; list_add(&avc->same_vma, &vma->anon_vma_chain); |
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list_add_tail(&avc->same_anon_vma, &anon_vma->head); |
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allocated = NULL; |
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avc = NULL; |
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} spin_unlock(&mm->page_table_lock); |
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anon_vma_unlock(anon_vma); |
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if (unlikely(allocated)) |
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put_anon_vma(allocated); |
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if (unlikely(avc)) |
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anon_vma_chain_free(avc); |
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} return 0; |
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out_enomem_free_avc: anon_vma_chain_free(avc); out_enomem: return -ENOMEM; |
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} |
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/* * This is a useful helper function for locking the anon_vma root as * we traverse the vma->anon_vma_chain, looping over anon_vma's that * have the same vma. * * Such anon_vma's should have the same root, so you'd expect to see * just a single mutex_lock for the whole traversal. */ static inline struct anon_vma *lock_anon_vma_root(struct anon_vma *root, struct anon_vma *anon_vma) { struct anon_vma *new_root = anon_vma->root; if (new_root != root) { if (WARN_ON_ONCE(root)) mutex_unlock(&root->mutex); root = new_root; mutex_lock(&root->mutex); } return root; } static inline void unlock_anon_vma_root(struct anon_vma *root) { if (root) mutex_unlock(&root->mutex); } |
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static void anon_vma_chain_link(struct vm_area_struct *vma, struct anon_vma_chain *avc, struct anon_vma *anon_vma) |
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{ |
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avc->vma = vma; avc->anon_vma = anon_vma; list_add(&avc->same_vma, &vma->anon_vma_chain); |
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/* * It's critical to add new vmas to the tail of the anon_vma, * see comment in huge_memory.c:__split_huge_page(). */ |
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list_add_tail(&avc->same_anon_vma, &anon_vma->head); |
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} |
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/* * Attach the anon_vmas from src to dst. * Returns 0 on success, -ENOMEM on failure. */ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src) |
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{ |
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struct anon_vma_chain *avc, *pavc; |
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struct anon_vma *root = NULL; |
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|
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list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) { |
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struct anon_vma *anon_vma; |
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avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN); if (unlikely(!avc)) { unlock_anon_vma_root(root); root = NULL; avc = anon_vma_chain_alloc(GFP_KERNEL); if (!avc) goto enomem_failure; } |
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anon_vma = pavc->anon_vma; root = lock_anon_vma_root(root, anon_vma); anon_vma_chain_link(dst, avc, anon_vma); |
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} |
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unlock_anon_vma_root(root); |
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return 0; |
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|
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enomem_failure: unlink_anon_vmas(dst); return -ENOMEM; |
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} |
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/* * Attach vma to its own anon_vma, as well as to the anon_vmas that * the corresponding VMA in the parent process is attached to. * Returns 0 on success, non-zero on failure. */ int anon_vma_fork(struct vm_area_struct *vma, struct vm_area_struct *pvma) |
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{ |
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struct anon_vma_chain *avc; struct anon_vma *anon_vma; |
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|
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/* Don't bother if the parent process has no anon_vma here. */ if (!pvma->anon_vma) return 0; /* * First, attach the new VMA to the parent VMA's anon_vmas, * so rmap can find non-COWed pages in child processes. */ if (anon_vma_clone(vma, pvma)) return -ENOMEM; /* Then add our own anon_vma. */ anon_vma = anon_vma_alloc(); if (!anon_vma) goto out_error; |
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avc = anon_vma_chain_alloc(GFP_KERNEL); |
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if (!avc) goto out_error_free_anon_vma; |
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/* * The root anon_vma's spinlock is the lock actually used when we * lock any of the anon_vmas in this anon_vma tree. */ anon_vma->root = pvma->anon_vma->root; |
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/* |
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* With refcounts, an anon_vma can stay around longer than the * process it belongs to. The root anon_vma needs to be pinned until * this anon_vma is freed, because the lock lives in the root. |
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*/ get_anon_vma(anon_vma->root); |
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/* Mark this anon_vma as the one where our new (COWed) pages go. */ vma->anon_vma = anon_vma; |
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anon_vma_lock(anon_vma); |
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anon_vma_chain_link(vma, avc, anon_vma); |
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anon_vma_unlock(anon_vma); |
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return 0; out_error_free_anon_vma: |
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put_anon_vma(anon_vma); |
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out_error: |
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unlink_anon_vmas(vma); |
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return -ENOMEM; |
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} |
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void unlink_anon_vmas(struct vm_area_struct *vma) { struct anon_vma_chain *avc, *next; |
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struct anon_vma *root = NULL; |
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|
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/* * Unlink each anon_vma chained to the VMA. This list is ordered * from newest to oldest, ensuring the root anon_vma gets freed last. */ |
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list_for_each_entry_safe(avc, next, &vma->anon_vma_chain, same_vma) { |
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struct anon_vma *anon_vma = avc->anon_vma; root = lock_anon_vma_root(root, anon_vma); list_del(&avc->same_anon_vma); /* * Leave empty anon_vmas on the list - we'll need * to free them outside the lock. */ if (list_empty(&anon_vma->head)) continue; list_del(&avc->same_vma); anon_vma_chain_free(avc); } unlock_anon_vma_root(root); /* * Iterate the list once more, it now only contains empty and unlinked * anon_vmas, destroy them. Could not do before due to __put_anon_vma() * needing to acquire the anon_vma->root->mutex. */ list_for_each_entry_safe(avc, next, &vma->anon_vma_chain, same_vma) { struct anon_vma *anon_vma = avc->anon_vma; put_anon_vma(anon_vma); |
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list_del(&avc->same_vma); anon_vma_chain_free(avc); } } |
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static void anon_vma_ctor(void *data) |
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{ |
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struct anon_vma *anon_vma = data; |
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|
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mutex_init(&anon_vma->mutex); |
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atomic_set(&anon_vma->refcount, 0); |
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INIT_LIST_HEAD(&anon_vma->head); |
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} void __init anon_vma_init(void) { anon_vma_cachep = kmem_cache_create("anon_vma", sizeof(struct anon_vma), |
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0, SLAB_DESTROY_BY_RCU|SLAB_PANIC, anon_vma_ctor); |
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anon_vma_chain_cachep = KMEM_CACHE(anon_vma_chain, SLAB_PANIC); |
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} /* |
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* Getting a lock on a stable anon_vma from a page off the LRU is tricky! * * Since there is no serialization what so ever against page_remove_rmap() * the best this function can do is return a locked anon_vma that might * have been relevant to this page. * * The page might have been remapped to a different anon_vma or the anon_vma * returned may already be freed (and even reused). * |
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* In case it was remapped to a different anon_vma, the new anon_vma will be a * child of the old anon_vma, and the anon_vma lifetime rules will therefore * ensure that any anon_vma obtained from the page will still be valid for as * long as we observe page_mapped() [ hence all those page_mapped() tests ]. * |
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* All users of this function must be very careful when walking the anon_vma * chain and verify that the page in question is indeed mapped in it * [ something equivalent to page_mapped_in_vma() ]. * * Since anon_vma's slab is DESTROY_BY_RCU and we know from page_remove_rmap() * that the anon_vma pointer from page->mapping is valid if there is a * mapcount, we can dereference the anon_vma after observing those. |
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*/ |
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struct anon_vma *page_get_anon_vma(struct page *page) |
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{ |
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struct anon_vma *anon_vma = NULL; |
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unsigned long anon_mapping; rcu_read_lock(); |
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anon_mapping = (unsigned long) ACCESS_ONCE(page->mapping); |
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if ((anon_mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON) |
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goto out; if (!page_mapped(page)) goto out; anon_vma = (struct anon_vma *) (anon_mapping - PAGE_MAPPING_ANON); |
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if (!atomic_inc_not_zero(&anon_vma->refcount)) { anon_vma = NULL; goto out; } |
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/* * If this page is still mapped, then its anon_vma cannot have been |
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* freed. But if it has been unmapped, we have no security against the * anon_vma structure being freed and reused (for another anon_vma: * SLAB_DESTROY_BY_RCU guarantees that - so the atomic_inc_not_zero() * above cannot corrupt). |
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*/ |
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if (!page_mapped(page)) { put_anon_vma(anon_vma); anon_vma = NULL; } |
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out: rcu_read_unlock(); |
746b18d42 mm: use refcounts... |
424 425 426 |
return anon_vma; } |
88c22088b mm: optimize page... |
427 428 429 430 431 432 433 |
/* * Similar to page_get_anon_vma() except it locks the anon_vma. * * Its a little more complex as it tries to keep the fast path to a single * atomic op -- the trylock. If we fail the trylock, we fall back to getting a * reference like with page_get_anon_vma() and then block on the mutex. */ |
746b18d42 mm: use refcounts... |
434 435 |
struct anon_vma *page_lock_anon_vma(struct page *page) { |
88c22088b mm: optimize page... |
436 |
struct anon_vma *anon_vma = NULL; |
eee0f252c mm: fix page_lock... |
437 |
struct anon_vma *root_anon_vma; |
88c22088b mm: optimize page... |
438 |
unsigned long anon_mapping; |
746b18d42 mm: use refcounts... |
439 |
|
88c22088b mm: optimize page... |
440 441 442 443 444 445 446 447 |
rcu_read_lock(); anon_mapping = (unsigned long) ACCESS_ONCE(page->mapping); if ((anon_mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON) goto out; if (!page_mapped(page)) goto out; anon_vma = (struct anon_vma *) (anon_mapping - PAGE_MAPPING_ANON); |
eee0f252c mm: fix page_lock... |
448 449 |
root_anon_vma = ACCESS_ONCE(anon_vma->root); if (mutex_trylock(&root_anon_vma->mutex)) { |
88c22088b mm: optimize page... |
450 |
/* |
eee0f252c mm: fix page_lock... |
451 452 |
* If the page is still mapped, then this anon_vma is still * its anon_vma, and holding the mutex ensures that it will |
bc658c960 mm, rmap: Add yet... |
453 |
* not go away, see anon_vma_free(). |
88c22088b mm: optimize page... |
454 |
*/ |
eee0f252c mm: fix page_lock... |
455 456 |
if (!page_mapped(page)) { mutex_unlock(&root_anon_vma->mutex); |
88c22088b mm: optimize page... |
457 458 459 460 |
anon_vma = NULL; } goto out; } |
746b18d42 mm: use refcounts... |
461 |
|
88c22088b mm: optimize page... |
462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 |
/* trylock failed, we got to sleep */ if (!atomic_inc_not_zero(&anon_vma->refcount)) { anon_vma = NULL; goto out; } if (!page_mapped(page)) { put_anon_vma(anon_vma); anon_vma = NULL; goto out; } /* we pinned the anon_vma, its safe to sleep */ rcu_read_unlock(); anon_vma_lock(anon_vma); if (atomic_dec_and_test(&anon_vma->refcount)) { /* * Oops, we held the last refcount, release the lock * and bail -- can't simply use put_anon_vma() because * we'll deadlock on the anon_vma_lock() recursion. */ anon_vma_unlock(anon_vma); __put_anon_vma(anon_vma); anon_vma = NULL; } return anon_vma; out: rcu_read_unlock(); |
746b18d42 mm: use refcounts... |
493 |
return anon_vma; |
34bbd7040 [PATCH] adapt pag... |
494 |
} |
10be22dfe HWPOISON: Export ... |
495 |
void page_unlock_anon_vma(struct anon_vma *anon_vma) |
34bbd7040 [PATCH] adapt pag... |
496 |
{ |
cba48b98f mm: change direct... |
497 |
anon_vma_unlock(anon_vma); |
1da177e4c Linux-2.6.12-rc2 |
498 499 500 |
} /* |
3ad33b243 Migration: find c... |
501 502 503 |
* At what user virtual address is page expected in @vma? * Returns virtual address or -EFAULT if page's index/offset is not * within the range mapped the @vma. |
1da177e4c Linux-2.6.12-rc2 |
504 |
*/ |
71e3aac07 thp: transparent ... |
505 |
inline unsigned long |
1da177e4c Linux-2.6.12-rc2 |
506 507 508 509 |
vma_address(struct page *page, struct vm_area_struct *vma) { pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); unsigned long address; |
0fe6e20b9 hugetlb, rmap: ad... |
510 511 |
if (unlikely(is_vm_hugetlb_page(vma))) pgoff = page->index << huge_page_order(page_hstate(page)); |
1da177e4c Linux-2.6.12-rc2 |
512 513 |
address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); if (unlikely(address < vma->vm_start || address >= vma->vm_end)) { |
3ad33b243 Migration: find c... |
514 |
/* page should be within @vma mapping range */ |
1da177e4c Linux-2.6.12-rc2 |
515 516 517 518 519 520 |
return -EFAULT; } return address; } /* |
bf89c8c86 mm/rmap.c: fix co... |
521 |
* At what user virtual address is page expected in vma? |
ab941e0ff rmap: remove anon... |
522 |
* Caller should check the page is actually part of the vma. |
1da177e4c Linux-2.6.12-rc2 |
523 524 525 |
*/ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) { |
21d0d443c rmap: resurrect p... |
526 |
if (PageAnon(page)) { |
4829b906c ksm: fix page_add... |
527 528 529 530 531 532 533 |
struct anon_vma *page__anon_vma = page_anon_vma(page); /* * Note: swapoff's unuse_vma() is more efficient with this * check, and needs it to match anon_vma when KSM is active. */ if (!vma->anon_vma || !page__anon_vma || vma->anon_vma->root != page__anon_vma->root) |
21d0d443c rmap: resurrect p... |
534 535 |
return -EFAULT; } else if (page->mapping && !(vma->vm_flags & VM_NONLINEAR)) { |
ee498ed73 [PATCH] unpaged: ... |
536 537 |
if (!vma->vm_file || vma->vm_file->f_mapping != page->mapping) |
1da177e4c Linux-2.6.12-rc2 |
538 539 540 541 542 543 544 |
return -EFAULT; } else return -EFAULT; return vma_address(page, vma); } /* |
81b4082dc [PATCH] mm: rmap.... |
545 546 |
* Check that @page is mapped at @address into @mm. * |
479db0bf4 mm: dirty page tr... |
547 548 549 550 |
* If @sync is false, page_check_address may perform a racy check to avoid * the page table lock when the pte is not present (helpful when reclaiming * highly shared pages). * |
b8072f099 [PATCH] mm: updat... |
551 |
* On success returns with pte mapped and locked. |
81b4082dc [PATCH] mm: rmap.... |
552 |
*/ |
e9a81a821 rmap: wrap page_c... |
553 |
pte_t *__page_check_address(struct page *page, struct mm_struct *mm, |
479db0bf4 mm: dirty page tr... |
554 |
unsigned long address, spinlock_t **ptlp, int sync) |
81b4082dc [PATCH] mm: rmap.... |
555 556 557 558 559 |
{ pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; |
c0718806c [PATCH] mm: rmap ... |
560 |
spinlock_t *ptl; |
81b4082dc [PATCH] mm: rmap.... |
561 |
|
0fe6e20b9 hugetlb, rmap: ad... |
562 563 564 565 566 |
if (unlikely(PageHuge(page))) { pte = huge_pte_offset(mm, address); ptl = &mm->page_table_lock; goto check; } |
81b4082dc [PATCH] mm: rmap.... |
567 |
pgd = pgd_offset(mm, address); |
c0718806c [PATCH] mm: rmap ... |
568 569 570 571 572 573 574 575 576 577 |
if (!pgd_present(*pgd)) return NULL; pud = pud_offset(pgd, address); if (!pud_present(*pud)) return NULL; pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) return NULL; |
71e3aac07 thp: transparent ... |
578 579 |
if (pmd_trans_huge(*pmd)) return NULL; |
c0718806c [PATCH] mm: rmap ... |
580 581 582 |
pte = pte_offset_map(pmd, address); /* Make a quick check before getting the lock */ |
479db0bf4 mm: dirty page tr... |
583 |
if (!sync && !pte_present(*pte)) { |
c0718806c [PATCH] mm: rmap ... |
584 585 586 |
pte_unmap(pte); return NULL; } |
4c21e2f24 [PATCH] mm: split... |
587 |
ptl = pte_lockptr(mm, pmd); |
0fe6e20b9 hugetlb, rmap: ad... |
588 |
check: |
c0718806c [PATCH] mm: rmap ... |
589 590 591 592 |
spin_lock(ptl); if (pte_present(*pte) && page_to_pfn(page) == pte_pfn(*pte)) { *ptlp = ptl; return pte; |
81b4082dc [PATCH] mm: rmap.... |
593 |
} |
c0718806c [PATCH] mm: rmap ... |
594 595 |
pte_unmap_unlock(pte, ptl); return NULL; |
81b4082dc [PATCH] mm: rmap.... |
596 |
} |
b291f0003 mlock: mlocked pa... |
597 598 599 600 601 602 603 604 605 |
/** * page_mapped_in_vma - check whether a page is really mapped in a VMA * @page: the page to test * @vma: the VMA to test * * Returns 1 if the page is mapped into the page tables of the VMA, 0 * if the page is not mapped into the page tables of this VMA. Only * valid for normal file or anonymous VMAs. */ |
6a46079cf HWPOISON: The hig... |
606 |
int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma) |
b291f0003 mlock: mlocked pa... |
607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 |
{ unsigned long address; pte_t *pte; spinlock_t *ptl; address = vma_address(page, vma); if (address == -EFAULT) /* out of vma range */ return 0; pte = page_check_address(page, vma->vm_mm, address, &ptl, 1); if (!pte) /* the page is not in this mm */ return 0; pte_unmap_unlock(pte, ptl); return 1; } |
81b4082dc [PATCH] mm: rmap.... |
622 |
/* |
1da177e4c Linux-2.6.12-rc2 |
623 624 625 |
* Subfunctions of page_referenced: page_referenced_one called * repeatedly from either page_referenced_anon or page_referenced_file. */ |
5ad646880 ksm: let shared p... |
626 627 628 |
int page_referenced_one(struct page *page, struct vm_area_struct *vma, unsigned long address, unsigned int *mapcount, unsigned long *vm_flags) |
1da177e4c Linux-2.6.12-rc2 |
629 630 |
{ struct mm_struct *mm = vma->vm_mm; |
1da177e4c Linux-2.6.12-rc2 |
631 |
int referenced = 0; |
71e3aac07 thp: transparent ... |
632 633 634 635 |
if (unlikely(PageTransHuge(page))) { pmd_t *pmd; spin_lock(&mm->page_table_lock); |
2da28bfd9 thp: fix page_ref... |
636 637 638 639 |
/* * rmap might return false positives; we must filter * these out using page_check_address_pmd(). */ |
71e3aac07 thp: transparent ... |
640 641 |
pmd = page_check_address_pmd(page, mm, address, PAGE_CHECK_ADDRESS_PMD_FLAG); |
2da28bfd9 thp: fix page_ref... |
642 643 644 645 646 647 648 649 650 651 652 653 654 655 |
if (!pmd) { spin_unlock(&mm->page_table_lock); goto out; } if (vma->vm_flags & VM_LOCKED) { spin_unlock(&mm->page_table_lock); *mapcount = 0; /* break early from loop */ *vm_flags |= VM_LOCKED; goto out; } /* go ahead even if the pmd is pmd_trans_splitting() */ if (pmdp_clear_flush_young_notify(vma, address, pmd)) |
71e3aac07 thp: transparent ... |
656 657 658 659 660 |
referenced++; spin_unlock(&mm->page_table_lock); } else { pte_t *pte; spinlock_t *ptl; |
2da28bfd9 thp: fix page_ref... |
661 662 663 664 |
/* * rmap might return false positives; we must filter * these out using page_check_address(). */ |
71e3aac07 thp: transparent ... |
665 666 667 |
pte = page_check_address(page, mm, address, &ptl, 0); if (!pte) goto out; |
2da28bfd9 thp: fix page_ref... |
668 669 670 671 672 673 |
if (vma->vm_flags & VM_LOCKED) { pte_unmap_unlock(pte, ptl); *mapcount = 0; /* break early from loop */ *vm_flags |= VM_LOCKED; goto out; } |
71e3aac07 thp: transparent ... |
674 675 676 677 678 679 680 681 682 683 684 685 686 |
if (ptep_clear_flush_young_notify(vma, address, pte)) { /* * Don't treat a reference through a sequentially read * mapping as such. If the page has been used in * another mapping, we will catch it; if this other * mapping is already gone, the unmap path will have * set PG_referenced or activated the page. */ if (likely(!VM_SequentialReadHint(vma))) referenced++; } pte_unmap_unlock(pte, ptl); } |
2da28bfd9 thp: fix page_ref... |
687 688 689 690 691 |
/* Pretend the page is referenced if the task has the swap token and is in the middle of a page fault. */ if (mm != current->mm && has_swap_token(mm) && rwsem_is_locked(&mm->mmap_sem)) referenced++; |
c0718806c [PATCH] mm: rmap ... |
692 |
(*mapcount)--; |
273f047e3 rmap: move label ... |
693 |
|
6fe6b7e35 vmscan: report vm... |
694 695 |
if (referenced) *vm_flags |= vma->vm_flags; |
273f047e3 rmap: move label ... |
696 |
out: |
1da177e4c Linux-2.6.12-rc2 |
697 698 |
return referenced; } |
bed7161a5 Memory controller... |
699 |
static int page_referenced_anon(struct page *page, |
6fe6b7e35 vmscan: report vm... |
700 701 |
struct mem_cgroup *mem_cont, unsigned long *vm_flags) |
1da177e4c Linux-2.6.12-rc2 |
702 703 704 |
{ unsigned int mapcount; struct anon_vma *anon_vma; |
5beb49305 mm: change anon_v... |
705 |
struct anon_vma_chain *avc; |
1da177e4c Linux-2.6.12-rc2 |
706 707 708 709 710 711 712 |
int referenced = 0; anon_vma = page_lock_anon_vma(page); if (!anon_vma) return referenced; mapcount = page_mapcount(page); |
5beb49305 mm: change anon_v... |
713 714 |
list_for_each_entry(avc, &anon_vma->head, same_anon_vma) { struct vm_area_struct *vma = avc->vma; |
1cb1729b1 mm: pass address ... |
715 716 717 |
unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; |
bed7161a5 Memory controller... |
718 719 720 721 722 |
/* * If we are reclaiming on behalf of a cgroup, skip * counting on behalf of references from different * cgroups */ |
bd845e38c memcg: mm_match_c... |
723 |
if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont)) |
bed7161a5 Memory controller... |
724 |
continue; |
1cb1729b1 mm: pass address ... |
725 |
referenced += page_referenced_one(page, vma, address, |
6fe6b7e35 vmscan: report vm... |
726 |
&mapcount, vm_flags); |
1da177e4c Linux-2.6.12-rc2 |
727 728 729 |
if (!mapcount) break; } |
34bbd7040 [PATCH] adapt pag... |
730 731 |
page_unlock_anon_vma(anon_vma); |
1da177e4c Linux-2.6.12-rc2 |
732 733 734 735 736 737 |
return referenced; } /** * page_referenced_file - referenced check for object-based rmap * @page: the page we're checking references on. |
43d8eac44 mm: rmap kernel-d... |
738 |
* @mem_cont: target memory controller |
6fe6b7e35 vmscan: report vm... |
739 |
* @vm_flags: collect encountered vma->vm_flags who actually referenced the page |
1da177e4c Linux-2.6.12-rc2 |
740 741 742 743 744 745 746 747 |
* * For an object-based mapped page, find all the places it is mapped and * check/clear the referenced flag. This is done by following the page->mapping * pointer, then walking the chain of vmas it holds. It returns the number * of references it found. * * This function is only called from page_referenced for object-based pages. */ |
bed7161a5 Memory controller... |
748 |
static int page_referenced_file(struct page *page, |
6fe6b7e35 vmscan: report vm... |
749 750 |
struct mem_cgroup *mem_cont, unsigned long *vm_flags) |
1da177e4c Linux-2.6.12-rc2 |
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 |
{ unsigned int mapcount; struct address_space *mapping = page->mapping; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); struct vm_area_struct *vma; struct prio_tree_iter iter; int referenced = 0; /* * The caller's checks on page->mapping and !PageAnon have made * sure that this is a file page: the check for page->mapping * excludes the case just before it gets set on an anon page. */ BUG_ON(PageAnon(page)); /* * The page lock not only makes sure that page->mapping cannot * suddenly be NULLified by truncation, it makes sure that the * structure at mapping cannot be freed and reused yet, |
3d48ae45e mm: Convert i_mma... |
770 |
* so we can safely take mapping->i_mmap_mutex. |
1da177e4c Linux-2.6.12-rc2 |
771 772 |
*/ BUG_ON(!PageLocked(page)); |
3d48ae45e mm: Convert i_mma... |
773 |
mutex_lock(&mapping->i_mmap_mutex); |
1da177e4c Linux-2.6.12-rc2 |
774 775 |
/* |
3d48ae45e mm: Convert i_mma... |
776 |
* i_mmap_mutex does not stabilize mapcount at all, but mapcount |
1da177e4c Linux-2.6.12-rc2 |
777 778 779 780 781 |
* is more likely to be accurate if we note it after spinning. */ mapcount = page_mapcount(page); vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { |
1cb1729b1 mm: pass address ... |
782 783 784 |
unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; |
bed7161a5 Memory controller... |
785 786 787 788 789 |
/* * If we are reclaiming on behalf of a cgroup, skip * counting on behalf of references from different * cgroups */ |
bd845e38c memcg: mm_match_c... |
790 |
if (mem_cont && !mm_match_cgroup(vma->vm_mm, mem_cont)) |
bed7161a5 Memory controller... |
791 |
continue; |
1cb1729b1 mm: pass address ... |
792 |
referenced += page_referenced_one(page, vma, address, |
6fe6b7e35 vmscan: report vm... |
793 |
&mapcount, vm_flags); |
1da177e4c Linux-2.6.12-rc2 |
794 795 796 |
if (!mapcount) break; } |
3d48ae45e mm: Convert i_mma... |
797 |
mutex_unlock(&mapping->i_mmap_mutex); |
1da177e4c Linux-2.6.12-rc2 |
798 799 800 801 802 803 804 |
return referenced; } /** * page_referenced - test if the page was referenced * @page: the page to test * @is_locked: caller holds lock on the page |
43d8eac44 mm: rmap kernel-d... |
805 |
* @mem_cont: target memory controller |
6fe6b7e35 vmscan: report vm... |
806 |
* @vm_flags: collect encountered vma->vm_flags who actually referenced the page |
1da177e4c Linux-2.6.12-rc2 |
807 808 809 810 |
* * Quick test_and_clear_referenced for all mappings to a page, * returns the number of ptes which referenced the page. */ |
6fe6b7e35 vmscan: report vm... |
811 812 813 814 |
int page_referenced(struct page *page, int is_locked, struct mem_cgroup *mem_cont, unsigned long *vm_flags) |
1da177e4c Linux-2.6.12-rc2 |
815 816 |
{ int referenced = 0; |
5ad646880 ksm: let shared p... |
817 |
int we_locked = 0; |
1da177e4c Linux-2.6.12-rc2 |
818 |
|
6fe6b7e35 vmscan: report vm... |
819 |
*vm_flags = 0; |
3ca7b3c5b mm: define PAGE_M... |
820 |
if (page_mapped(page) && page_rmapping(page)) { |
5ad646880 ksm: let shared p... |
821 822 823 824 825 826 827 828 829 830 831 |
if (!is_locked && (!PageAnon(page) || PageKsm(page))) { we_locked = trylock_page(page); if (!we_locked) { referenced++; goto out; } } if (unlikely(PageKsm(page))) referenced += page_referenced_ksm(page, mem_cont, vm_flags); else if (PageAnon(page)) |
6fe6b7e35 vmscan: report vm... |
832 833 |
referenced += page_referenced_anon(page, mem_cont, vm_flags); |
5ad646880 ksm: let shared p... |
834 |
else if (page->mapping) |
6fe6b7e35 vmscan: report vm... |
835 836 |
referenced += page_referenced_file(page, mem_cont, vm_flags); |
5ad646880 ksm: let shared p... |
837 |
if (we_locked) |
1da177e4c Linux-2.6.12-rc2 |
838 |
unlock_page(page); |
50a15981a [S390] reference ... |
839 840 841 |
if (page_test_and_clear_young(page_to_pfn(page))) referenced++; |
1da177e4c Linux-2.6.12-rc2 |
842 |
} |
5ad646880 ksm: let shared p... |
843 |
out: |
1da177e4c Linux-2.6.12-rc2 |
844 845 |
return referenced; } |
1cb1729b1 mm: pass address ... |
846 847 |
static int page_mkclean_one(struct page *page, struct vm_area_struct *vma, unsigned long address) |
d08b3851d [PATCH] mm: track... |
848 849 |
{ struct mm_struct *mm = vma->vm_mm; |
c2fda5fed [PATCH] Fix up pa... |
850 |
pte_t *pte; |
d08b3851d [PATCH] mm: track... |
851 852 |
spinlock_t *ptl; int ret = 0; |
479db0bf4 mm: dirty page tr... |
853 |
pte = page_check_address(page, mm, address, &ptl, 1); |
d08b3851d [PATCH] mm: track... |
854 855 |
if (!pte) goto out; |
c2fda5fed [PATCH] Fix up pa... |
856 857 |
if (pte_dirty(*pte) || pte_write(*pte)) { pte_t entry; |
d08b3851d [PATCH] mm: track... |
858 |
|
c2fda5fed [PATCH] Fix up pa... |
859 |
flush_cache_page(vma, address, pte_pfn(*pte)); |
cddb8a5c1 mmu-notifiers: core |
860 |
entry = ptep_clear_flush_notify(vma, address, pte); |
c2fda5fed [PATCH] Fix up pa... |
861 862 |
entry = pte_wrprotect(entry); entry = pte_mkclean(entry); |
d6e88e671 [PATCH] page_mkcl... |
863 |
set_pte_at(mm, address, pte, entry); |
c2fda5fed [PATCH] Fix up pa... |
864 865 |
ret = 1; } |
d08b3851d [PATCH] mm: track... |
866 |
|
d08b3851d [PATCH] mm: track... |
867 868 869 870 871 872 873 874 875 876 877 878 879 |
pte_unmap_unlock(pte, ptl); out: return ret; } static int page_mkclean_file(struct address_space *mapping, struct page *page) { pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); struct vm_area_struct *vma; struct prio_tree_iter iter; int ret = 0; BUG_ON(PageAnon(page)); |
3d48ae45e mm: Convert i_mma... |
880 |
mutex_lock(&mapping->i_mmap_mutex); |
d08b3851d [PATCH] mm: track... |
881 |
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { |
1cb1729b1 mm: pass address ... |
882 883 884 885 886 887 |
if (vma->vm_flags & VM_SHARED) { unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; ret += page_mkclean_one(page, vma, address); } |
d08b3851d [PATCH] mm: track... |
888 |
} |
3d48ae45e mm: Convert i_mma... |
889 |
mutex_unlock(&mapping->i_mmap_mutex); |
d08b3851d [PATCH] mm: track... |
890 891 892 893 894 895 896 897 898 899 900 |
return ret; } int page_mkclean(struct page *page) { int ret = 0; BUG_ON(!PageLocked(page)); if (page_mapped(page)) { struct address_space *mapping = page_mapping(page); |
ce7e9fae8 [S390] Optimize s... |
901 |
if (mapping) { |
d08b3851d [PATCH] mm: track... |
902 |
ret = page_mkclean_file(mapping, page); |
2d42552d1 [S390] merge page... |
903 |
if (page_test_and_clear_dirty(page_to_pfn(page), 1)) |
ce7e9fae8 [S390] Optimize s... |
904 |
ret = 1; |
6c210482a [S390] split page... |
905 |
} |
d08b3851d [PATCH] mm: track... |
906 907 908 909 |
} return ret; } |
60b59beaf fbdev: mm: Deferr... |
910 |
EXPORT_SYMBOL_GPL(page_mkclean); |
d08b3851d [PATCH] mm: track... |
911 |
|
1da177e4c Linux-2.6.12-rc2 |
912 |
/** |
c44b67432 rmap: move exclus... |
913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 |
* page_move_anon_rmap - move a page to our anon_vma * @page: the page to move to our anon_vma * @vma: the vma the page belongs to * @address: the user virtual address mapped * * When a page belongs exclusively to one process after a COW event, * that page can be moved into the anon_vma that belongs to just that * process, so the rmap code will not search the parent or sibling * processes. */ void page_move_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { struct anon_vma *anon_vma = vma->anon_vma; VM_BUG_ON(!PageLocked(page)); VM_BUG_ON(!anon_vma); VM_BUG_ON(page->index != linear_page_index(vma, address)); anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; page->mapping = (struct address_space *) anon_vma; } /** |
4e1c19750 Clean up __page_s... |
937 938 939 940 |
* __page_set_anon_rmap - set up new anonymous rmap * @page: Page to add to rmap * @vma: VM area to add page to. * @address: User virtual address of the mapping |
e8a03feb5 rmap: add exclusi... |
941 |
* @exclusive: the page is exclusively owned by the current process |
9617d95e6 [PATCH] mm: rmap ... |
942 943 |
*/ static void __page_set_anon_rmap(struct page *page, |
e8a03feb5 rmap: add exclusi... |
944 |
struct vm_area_struct *vma, unsigned long address, int exclusive) |
9617d95e6 [PATCH] mm: rmap ... |
945 |
{ |
e8a03feb5 rmap: add exclusi... |
946 |
struct anon_vma *anon_vma = vma->anon_vma; |
ea90002b0 anonvma: when set... |
947 |
|
e8a03feb5 rmap: add exclusi... |
948 |
BUG_ON(!anon_vma); |
ea90002b0 anonvma: when set... |
949 |
|
4e1c19750 Clean up __page_s... |
950 951 |
if (PageAnon(page)) return; |
ea90002b0 anonvma: when set... |
952 |
/* |
e8a03feb5 rmap: add exclusi... |
953 954 955 |
* If the page isn't exclusively mapped into this vma, * we must use the _oldest_ possible anon_vma for the * page mapping! |
ea90002b0 anonvma: when set... |
956 |
*/ |
4e1c19750 Clean up __page_s... |
957 |
if (!exclusive) |
288468c33 rmap: always use ... |
958 |
anon_vma = anon_vma->root; |
9617d95e6 [PATCH] mm: rmap ... |
959 |
|
9617d95e6 [PATCH] mm: rmap ... |
960 961 |
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; page->mapping = (struct address_space *) anon_vma; |
9617d95e6 [PATCH] mm: rmap ... |
962 |
page->index = linear_page_index(vma, address); |
9617d95e6 [PATCH] mm: rmap ... |
963 964 965 |
} /** |
43d8eac44 mm: rmap kernel-d... |
966 |
* __page_check_anon_rmap - sanity check anonymous rmap addition |
c97a9e10e mm: more rmap che... |
967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 |
* @page: the page to add the mapping to * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped */ static void __page_check_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { #ifdef CONFIG_DEBUG_VM /* * The page's anon-rmap details (mapping and index) are guaranteed to * be set up correctly at this point. * * We have exclusion against page_add_anon_rmap because the caller * always holds the page locked, except if called from page_dup_rmap, * in which case the page is already known to be setup. * * We have exclusion against page_add_new_anon_rmap because those pages * are initially only visible via the pagetables, and the pte is locked * over the call to page_add_new_anon_rmap. */ |
44ab57a06 rmap: add anon_vm... |
987 |
BUG_ON(page_anon_vma(page)->root != vma->anon_vma->root); |
c97a9e10e mm: more rmap che... |
988 989 990 991 992 |
BUG_ON(page->index != linear_page_index(vma, address)); #endif } /** |
1da177e4c Linux-2.6.12-rc2 |
993 994 995 996 997 |
* page_add_anon_rmap - add pte mapping to an anonymous page * @page: the page to add the mapping to * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped * |
5ad646880 ksm: let shared p... |
998 |
* The caller needs to hold the pte lock, and the page must be locked in |
80e148226 ksm: share anon p... |
999 1000 1001 |
* the anon_vma case: to serialize mapping,index checking after setting, * and to ensure that PageAnon is not being upgraded racily to PageKsm * (but PageKsm is never downgraded to PageAnon). |
1da177e4c Linux-2.6.12-rc2 |
1002 1003 1004 1005 |
*/ void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { |
ad8c2ee80 rmap: add exclusi... |
1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 |
do_page_add_anon_rmap(page, vma, address, 0); } /* * Special version of the above for do_swap_page, which often runs * into pages that are exclusively owned by the current process. * Everybody else should continue to use page_add_anon_rmap above. */ void do_page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address, int exclusive) { |
5ad646880 ksm: let shared p... |
1017 |
int first = atomic_inc_and_test(&page->_mapcount); |
79134171d thp: transparent ... |
1018 1019 1020 1021 1022 1023 1024 |
if (first) { if (!PageTransHuge(page)) __inc_zone_page_state(page, NR_ANON_PAGES); else __inc_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); } |
5ad646880 ksm: let shared p... |
1025 1026 |
if (unlikely(PageKsm(page))) return; |
c97a9e10e mm: more rmap che... |
1027 |
VM_BUG_ON(!PageLocked(page)); |
5dbe0af47 mm: fix kernel BU... |
1028 |
/* address might be in next vma when migration races vma_adjust */ |
5ad646880 ksm: let shared p... |
1029 |
if (first) |
ad8c2ee80 rmap: add exclusi... |
1030 |
__page_set_anon_rmap(page, vma, address, exclusive); |
69029cd55 memcg: remove ref... |
1031 |
else |
c97a9e10e mm: more rmap che... |
1032 |
__page_check_anon_rmap(page, vma, address); |
1da177e4c Linux-2.6.12-rc2 |
1033 |
} |
43d8eac44 mm: rmap kernel-d... |
1034 |
/** |
9617d95e6 [PATCH] mm: rmap ... |
1035 1036 1037 1038 1039 1040 1041 |
* page_add_new_anon_rmap - add pte mapping to a new anonymous page * @page: the page to add the mapping to * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped * * Same as page_add_anon_rmap but must only be called on *new* pages. * This means the inc-and-test can be bypassed. |
c97a9e10e mm: more rmap che... |
1042 |
* Page does not have to be locked. |
9617d95e6 [PATCH] mm: rmap ... |
1043 1044 1045 1046 |
*/ void page_add_new_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { |
b5934c531 mm: add_active_or... |
1047 |
VM_BUG_ON(address < vma->vm_start || address >= vma->vm_end); |
cbf84b7ad mm: further clean... |
1048 1049 |
SetPageSwapBacked(page); atomic_set(&page->_mapcount, 0); /* increment count (starts at -1) */ |
79134171d thp: transparent ... |
1050 1051 1052 1053 |
if (!PageTransHuge(page)) __inc_zone_page_state(page, NR_ANON_PAGES); else __inc_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); |
e8a03feb5 rmap: add exclusi... |
1054 |
__page_set_anon_rmap(page, vma, address, 1); |
b5934c531 mm: add_active_or... |
1055 |
if (page_evictable(page, vma)) |
cbf84b7ad mm: further clean... |
1056 |
lru_cache_add_lru(page, LRU_ACTIVE_ANON); |
b5934c531 mm: add_active_or... |
1057 1058 |
else add_page_to_unevictable_list(page); |
9617d95e6 [PATCH] mm: rmap ... |
1059 |
} |
1da177e4c Linux-2.6.12-rc2 |
1060 1061 1062 1063 |
/** * page_add_file_rmap - add pte mapping to a file page * @page: the page to add the mapping to * |
b8072f099 [PATCH] mm: updat... |
1064 |
* The caller needs to hold the pte lock. |
1da177e4c Linux-2.6.12-rc2 |
1065 1066 1067 |
*/ void page_add_file_rmap(struct page *page) { |
d69b042f3 memcg: add file-b... |
1068 |
if (atomic_inc_and_test(&page->_mapcount)) { |
65ba55f50 [PATCH] zoned vm ... |
1069 |
__inc_zone_page_state(page, NR_FILE_MAPPED); |
2a7106f2c memcg: create ext... |
1070 |
mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_MAPPED); |
d69b042f3 memcg: add file-b... |
1071 |
} |
1da177e4c Linux-2.6.12-rc2 |
1072 1073 1074 1075 1076 1077 |
} /** * page_remove_rmap - take down pte mapping from a page * @page: page to remove mapping from * |
b8072f099 [PATCH] mm: updat... |
1078 |
* The caller needs to hold the pte lock. |
1da177e4c Linux-2.6.12-rc2 |
1079 |
*/ |
edc315fd2 badpage: remove v... |
1080 |
void page_remove_rmap(struct page *page) |
1da177e4c Linux-2.6.12-rc2 |
1081 |
{ |
b904dcfed mm: clean up page... |
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 |
/* page still mapped by someone else? */ if (!atomic_add_negative(-1, &page->_mapcount)) return; /* * Now that the last pte has gone, s390 must transfer dirty * flag from storage key to struct page. We can usually skip * this if the page is anon, so about to be freed; but perhaps * not if it's in swapcache - there might be another pte slot * containing the swap entry, but page not yet written to swap. */ |
2d42552d1 [S390] merge page... |
1093 1094 |
if ((!PageAnon(page) || PageSwapCache(page)) && page_test_and_clear_dirty(page_to_pfn(page), 1)) |
b904dcfed mm: clean up page... |
1095 |
set_page_dirty(page); |
0fe6e20b9 hugetlb, rmap: ad... |
1096 1097 1098 1099 1100 1101 |
/* * Hugepages are not counted in NR_ANON_PAGES nor NR_FILE_MAPPED * and not charged by memcg for now. */ if (unlikely(PageHuge(page))) return; |
b904dcfed mm: clean up page... |
1102 1103 |
if (PageAnon(page)) { mem_cgroup_uncharge_page(page); |
79134171d thp: transparent ... |
1104 1105 1106 1107 1108 |
if (!PageTransHuge(page)) __dec_zone_page_state(page, NR_ANON_PAGES); else __dec_zone_page_state(page, NR_ANON_TRANSPARENT_HUGEPAGES); |
b904dcfed mm: clean up page... |
1109 1110 |
} else { __dec_zone_page_state(page, NR_FILE_MAPPED); |
2a7106f2c memcg: create ext... |
1111 |
mem_cgroup_dec_page_stat(page, MEMCG_NR_FILE_MAPPED); |
b904dcfed mm: clean up page... |
1112 |
} |
b904dcfed mm: clean up page... |
1113 1114 1115 1116 1117 1118 1119 1120 1121 |
/* * It would be tidy to reset the PageAnon mapping here, * but that might overwrite a racing page_add_anon_rmap * which increments mapcount after us but sets mapping * before us: so leave the reset to free_hot_cold_page, * and remember that it's only reliable while mapped. * Leaving it set also helps swapoff to reinstate ptes * faster for those pages still in swapcache. */ |
1da177e4c Linux-2.6.12-rc2 |
1122 1123 1124 1125 |
} /* * Subfunctions of try_to_unmap: try_to_unmap_one called |
99ef0315f ksm: fix the comm... |
1126 |
* repeatedly from try_to_unmap_ksm, try_to_unmap_anon or try_to_unmap_file. |
1da177e4c Linux-2.6.12-rc2 |
1127 |
*/ |
5ad646880 ksm: let shared p... |
1128 1129 |
int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, unsigned long address, enum ttu_flags flags) |
1da177e4c Linux-2.6.12-rc2 |
1130 1131 |
{ struct mm_struct *mm = vma->vm_mm; |
1da177e4c Linux-2.6.12-rc2 |
1132 1133 |
pte_t *pte; pte_t pteval; |
c0718806c [PATCH] mm: rmap ... |
1134 |
spinlock_t *ptl; |
1da177e4c Linux-2.6.12-rc2 |
1135 |
int ret = SWAP_AGAIN; |
479db0bf4 mm: dirty page tr... |
1136 |
pte = page_check_address(page, mm, address, &ptl, 0); |
c0718806c [PATCH] mm: rmap ... |
1137 |
if (!pte) |
81b4082dc [PATCH] mm: rmap.... |
1138 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
1139 1140 1141 1142 1143 1144 |
/* * If the page is mlock()d, we cannot swap it out. * If it's recently referenced (perhaps page_referenced * skipped over this mm) then we should reactivate it. */ |
14fa31b89 HWPOISON: Use bit... |
1145 |
if (!(flags & TTU_IGNORE_MLOCK)) { |
caed0f486 mm: simplify try_... |
1146 1147 |
if (vma->vm_flags & VM_LOCKED) goto out_mlock; |
af8e3354b mm: CONFIG_MMU fo... |
1148 |
if (TTU_ACTION(flags) == TTU_MUNLOCK) |
53f79acb6 mm: mlocking in t... |
1149 |
goto out_unmap; |
14fa31b89 HWPOISON: Use bit... |
1150 1151 |
} if (!(flags & TTU_IGNORE_ACCESS)) { |
b291f0003 mlock: mlocked pa... |
1152 1153 1154 1155 1156 |
if (ptep_clear_flush_young_notify(vma, address, pte)) { ret = SWAP_FAIL; goto out_unmap; } } |
1da177e4c Linux-2.6.12-rc2 |
1157 |
|
1da177e4c Linux-2.6.12-rc2 |
1158 1159 |
/* Nuke the page table entry. */ flush_cache_page(vma, address, page_to_pfn(page)); |
cddb8a5c1 mmu-notifiers: core |
1160 |
pteval = ptep_clear_flush_notify(vma, address, pte); |
1da177e4c Linux-2.6.12-rc2 |
1161 1162 1163 1164 |
/* Move the dirty bit to the physical page now the pte is gone. */ if (pte_dirty(pteval)) set_page_dirty(page); |
365e9c87a [PATCH] mm: updat... |
1165 1166 |
/* Update high watermark before we lower rss */ update_hiwater_rss(mm); |
888b9f7c5 HWPOISON: Handle ... |
1167 1168 |
if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) { if (PageAnon(page)) |
d559db086 mm: clean up mm_c... |
1169 |
dec_mm_counter(mm, MM_ANONPAGES); |
888b9f7c5 HWPOISON: Handle ... |
1170 |
else |
d559db086 mm: clean up mm_c... |
1171 |
dec_mm_counter(mm, MM_FILEPAGES); |
888b9f7c5 HWPOISON: Handle ... |
1172 1173 1174 |
set_pte_at(mm, address, pte, swp_entry_to_pte(make_hwpoison_entry(page))); } else if (PageAnon(page)) { |
4c21e2f24 [PATCH] mm: split... |
1175 |
swp_entry_t entry = { .val = page_private(page) }; |
0697212a4 [PATCH] Swapless ... |
1176 1177 1178 1179 1180 1181 |
if (PageSwapCache(page)) { /* * Store the swap location in the pte. * See handle_pte_fault() ... */ |
570a335b8 swap_info: swap c... |
1182 1183 1184 1185 1186 |
if (swap_duplicate(entry) < 0) { set_pte_at(mm, address, pte, pteval); ret = SWAP_FAIL; goto out_unmap; } |
0697212a4 [PATCH] Swapless ... |
1187 1188 1189 1190 1191 1192 |
if (list_empty(&mm->mmlist)) { spin_lock(&mmlist_lock); if (list_empty(&mm->mmlist)) list_add(&mm->mmlist, &init_mm.mmlist); spin_unlock(&mmlist_lock); } |
d559db086 mm: clean up mm_c... |
1193 |
dec_mm_counter(mm, MM_ANONPAGES); |
b084d4353 mm: count swap usage |
1194 |
inc_mm_counter(mm, MM_SWAPENTS); |
64cdd548f mm: cleanup: remo... |
1195 |
} else if (PAGE_MIGRATION) { |
0697212a4 [PATCH] Swapless ... |
1196 1197 1198 1199 1200 |
/* * Store the pfn of the page in a special migration * pte. do_swap_page() will wait until the migration * pte is removed and then restart fault handling. */ |
14fa31b89 HWPOISON: Use bit... |
1201 |
BUG_ON(TTU_ACTION(flags) != TTU_MIGRATION); |
0697212a4 [PATCH] Swapless ... |
1202 |
entry = make_migration_entry(page, pte_write(pteval)); |
1da177e4c Linux-2.6.12-rc2 |
1203 1204 1205 |
} set_pte_at(mm, address, pte, swp_entry_to_pte(entry)); BUG_ON(pte_file(*pte)); |
14fa31b89 HWPOISON: Use bit... |
1206 |
} else if (PAGE_MIGRATION && (TTU_ACTION(flags) == TTU_MIGRATION)) { |
04e62a29b [PATCH] More page... |
1207 1208 1209 1210 1211 |
/* Establish migration entry for a file page */ swp_entry_t entry; entry = make_migration_entry(page, pte_write(pteval)); set_pte_at(mm, address, pte, swp_entry_to_pte(entry)); } else |
d559db086 mm: clean up mm_c... |
1212 |
dec_mm_counter(mm, MM_FILEPAGES); |
1da177e4c Linux-2.6.12-rc2 |
1213 |
|
edc315fd2 badpage: remove v... |
1214 |
page_remove_rmap(page); |
1da177e4c Linux-2.6.12-rc2 |
1215 1216 1217 |
page_cache_release(page); out_unmap: |
c0718806c [PATCH] mm: rmap ... |
1218 |
pte_unmap_unlock(pte, ptl); |
caed0f486 mm: simplify try_... |
1219 1220 |
out: return ret; |
53f79acb6 mm: mlocking in t... |
1221 |
|
caed0f486 mm: simplify try_... |
1222 1223 1224 1225 1226 1227 1228 |
out_mlock: pte_unmap_unlock(pte, ptl); /* * We need mmap_sem locking, Otherwise VM_LOCKED check makes * unstable result and race. Plus, We can't wait here because |
2b575eb64 mm: convert anon_... |
1229 |
* we now hold anon_vma->mutex or mapping->i_mmap_mutex. |
caed0f486 mm: simplify try_... |
1230 1231 1232 1233 1234 1235 1236 1237 |
* if trylock failed, the page remain in evictable lru and later * vmscan could retry to move the page to unevictable lru if the * page is actually mlocked. */ if (down_read_trylock(&vma->vm_mm->mmap_sem)) { if (vma->vm_flags & VM_LOCKED) { mlock_vma_page(page); ret = SWAP_MLOCK; |
53f79acb6 mm: mlocking in t... |
1238 |
} |
caed0f486 mm: simplify try_... |
1239 |
up_read(&vma->vm_mm->mmap_sem); |
53f79acb6 mm: mlocking in t... |
1240 |
} |
1da177e4c Linux-2.6.12-rc2 |
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 |
return ret; } /* * objrmap doesn't work for nonlinear VMAs because the assumption that * offset-into-file correlates with offset-into-virtual-addresses does not hold. * Consequently, given a particular page and its ->index, we cannot locate the * ptes which are mapping that page without an exhaustive linear search. * * So what this code does is a mini "virtual scan" of each nonlinear VMA which * maps the file to which the target page belongs. The ->vm_private_data field * holds the current cursor into that scan. Successive searches will circulate * around the vma's virtual address space. * * So as more replacement pressure is applied to the pages in a nonlinear VMA, * more scanning pressure is placed against them as well. Eventually pages * will become fully unmapped and are eligible for eviction. * * For very sparsely populated VMAs this is a little inefficient - chances are * there there won't be many ptes located within the scan cluster. In this case * maybe we could scan further - to the end of the pte page, perhaps. |
b291f0003 mlock: mlocked pa... |
1262 1263 1264 1265 1266 |
* * Mlocked pages: check VM_LOCKED under mmap_sem held for read, if we can * acquire it without blocking. If vma locked, mlock the pages in the cluster, * rather than unmapping them. If we encounter the "check_page" that vmscan is * trying to unmap, return SWAP_MLOCK, else default SWAP_AGAIN. |
1da177e4c Linux-2.6.12-rc2 |
1267 1268 1269 |
*/ #define CLUSTER_SIZE min(32*PAGE_SIZE, PMD_SIZE) #define CLUSTER_MASK (~(CLUSTER_SIZE - 1)) |
b291f0003 mlock: mlocked pa... |
1270 1271 |
static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount, struct vm_area_struct *vma, struct page *check_page) |
1da177e4c Linux-2.6.12-rc2 |
1272 1273 1274 1275 1276 |
{ struct mm_struct *mm = vma->vm_mm; pgd_t *pgd; pud_t *pud; pmd_t *pmd; |
c0718806c [PATCH] mm: rmap ... |
1277 |
pte_t *pte; |
1da177e4c Linux-2.6.12-rc2 |
1278 |
pte_t pteval; |
c0718806c [PATCH] mm: rmap ... |
1279 |
spinlock_t *ptl; |
1da177e4c Linux-2.6.12-rc2 |
1280 1281 1282 |
struct page *page; unsigned long address; unsigned long end; |
b291f0003 mlock: mlocked pa... |
1283 1284 |
int ret = SWAP_AGAIN; int locked_vma = 0; |
1da177e4c Linux-2.6.12-rc2 |
1285 |
|
1da177e4c Linux-2.6.12-rc2 |
1286 1287 1288 1289 1290 1291 1292 1293 1294 |
address = (vma->vm_start + cursor) & CLUSTER_MASK; end = address + CLUSTER_SIZE; if (address < vma->vm_start) address = vma->vm_start; if (end > vma->vm_end) end = vma->vm_end; pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) |
b291f0003 mlock: mlocked pa... |
1295 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1296 1297 1298 |
pud = pud_offset(pgd, address); if (!pud_present(*pud)) |
b291f0003 mlock: mlocked pa... |
1299 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1300 1301 1302 |
pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) |
b291f0003 mlock: mlocked pa... |
1303 1304 1305 |
return ret; /* |
af8e3354b mm: CONFIG_MMU fo... |
1306 |
* If we can acquire the mmap_sem for read, and vma is VM_LOCKED, |
b291f0003 mlock: mlocked pa... |
1307 1308 |
* keep the sem while scanning the cluster for mlocking pages. */ |
af8e3354b mm: CONFIG_MMU fo... |
1309 |
if (down_read_trylock(&vma->vm_mm->mmap_sem)) { |
b291f0003 mlock: mlocked pa... |
1310 1311 1312 1313 |
locked_vma = (vma->vm_flags & VM_LOCKED); if (!locked_vma) up_read(&vma->vm_mm->mmap_sem); /* don't need it */ } |
c0718806c [PATCH] mm: rmap ... |
1314 1315 |
pte = pte_offset_map_lock(mm, pmd, address, &ptl); |
1da177e4c Linux-2.6.12-rc2 |
1316 |
|
365e9c87a [PATCH] mm: updat... |
1317 1318 |
/* Update high watermark before we lower rss */ update_hiwater_rss(mm); |
c0718806c [PATCH] mm: rmap ... |
1319 |
for (; address < end; pte++, address += PAGE_SIZE) { |
1da177e4c Linux-2.6.12-rc2 |
1320 1321 |
if (!pte_present(*pte)) continue; |
6aab341e0 mm: re-architect ... |
1322 1323 |
page = vm_normal_page(vma, address, *pte); BUG_ON(!page || PageAnon(page)); |
1da177e4c Linux-2.6.12-rc2 |
1324 |
|
b291f0003 mlock: mlocked pa... |
1325 1326 1327 1328 1329 1330 |
if (locked_vma) { mlock_vma_page(page); /* no-op if already mlocked */ if (page == check_page) ret = SWAP_MLOCK; continue; /* don't unmap */ } |
cddb8a5c1 mmu-notifiers: core |
1331 |
if (ptep_clear_flush_young_notify(vma, address, pte)) |
1da177e4c Linux-2.6.12-rc2 |
1332 1333 1334 |
continue; /* Nuke the page table entry. */ |
eca351336 [PATCH] Fix missi... |
1335 |
flush_cache_page(vma, address, pte_pfn(*pte)); |
cddb8a5c1 mmu-notifiers: core |
1336 |
pteval = ptep_clear_flush_notify(vma, address, pte); |
1da177e4c Linux-2.6.12-rc2 |
1337 1338 1339 1340 1341 1342 1343 1344 |
/* If nonlinear, store the file page offset in the pte. */ if (page->index != linear_page_index(vma, address)) set_pte_at(mm, address, pte, pgoff_to_pte(page->index)); /* Move the dirty bit to the physical page now the pte is gone. */ if (pte_dirty(pteval)) set_page_dirty(page); |
edc315fd2 badpage: remove v... |
1345 |
page_remove_rmap(page); |
1da177e4c Linux-2.6.12-rc2 |
1346 |
page_cache_release(page); |
d559db086 mm: clean up mm_c... |
1347 |
dec_mm_counter(mm, MM_FILEPAGES); |
1da177e4c Linux-2.6.12-rc2 |
1348 1349 |
(*mapcount)--; } |
c0718806c [PATCH] mm: rmap ... |
1350 |
pte_unmap_unlock(pte - 1, ptl); |
b291f0003 mlock: mlocked pa... |
1351 1352 1353 |
if (locked_vma) up_read(&vma->vm_mm->mmap_sem); return ret; |
1da177e4c Linux-2.6.12-rc2 |
1354 |
} |
71e3aac07 thp: transparent ... |
1355 |
bool is_vma_temporary_stack(struct vm_area_struct *vma) |
a8bef8ff6 mm: migration: av... |
1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 |
{ int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP); if (!maybe_stack) return false; if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) == VM_STACK_INCOMPLETE_SETUP) return true; return false; } |
b291f0003 mlock: mlocked pa... |
1368 1369 1370 1371 |
/** * try_to_unmap_anon - unmap or unlock anonymous page using the object-based * rmap method * @page: the page to unmap/unlock |
8051be5e6 rmap: fix the com... |
1372 |
* @flags: action and flags |
b291f0003 mlock: mlocked pa... |
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 |
* * Find all the mappings of a page using the mapping pointer and the vma chains * contained in the anon_vma struct it points to. * * This function is only called from try_to_unmap/try_to_munlock for * anonymous pages. * When called from try_to_munlock(), the mmap_sem of the mm containing the vma * where the page was found will be held for write. So, we won't recheck * vm_flags for that VMA. That should be OK, because that vma shouldn't be * 'LOCKED. */ |
14fa31b89 HWPOISON: Use bit... |
1384 |
static int try_to_unmap_anon(struct page *page, enum ttu_flags flags) |
1da177e4c Linux-2.6.12-rc2 |
1385 1386 |
{ struct anon_vma *anon_vma; |
5beb49305 mm: change anon_v... |
1387 |
struct anon_vma_chain *avc; |
1da177e4c Linux-2.6.12-rc2 |
1388 |
int ret = SWAP_AGAIN; |
b291f0003 mlock: mlocked pa... |
1389 |
|
1da177e4c Linux-2.6.12-rc2 |
1390 1391 1392 |
anon_vma = page_lock_anon_vma(page); if (!anon_vma) return ret; |
5beb49305 mm: change anon_v... |
1393 1394 |
list_for_each_entry(avc, &anon_vma->head, same_anon_vma) { struct vm_area_struct *vma = avc->vma; |
a8bef8ff6 mm: migration: av... |
1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 |
unsigned long address; /* * During exec, a temporary VMA is setup and later moved. * The VMA is moved under the anon_vma lock but not the * page tables leading to a race where migration cannot * find the migration ptes. Rather than increasing the * locking requirements of exec(), migration skips * temporary VMAs until after exec() completes. */ if (PAGE_MIGRATION && (flags & TTU_MIGRATION) && is_vma_temporary_stack(vma)) continue; address = vma_address(page, vma); |
1cb1729b1 mm: pass address ... |
1410 1411 1412 |
if (address == -EFAULT) continue; ret = try_to_unmap_one(page, vma, address, flags); |
53f79acb6 mm: mlocking in t... |
1413 1414 |
if (ret != SWAP_AGAIN || !page_mapped(page)) break; |
1da177e4c Linux-2.6.12-rc2 |
1415 |
} |
34bbd7040 [PATCH] adapt pag... |
1416 1417 |
page_unlock_anon_vma(anon_vma); |
1da177e4c Linux-2.6.12-rc2 |
1418 1419 1420 1421 |
return ret; } /** |
b291f0003 mlock: mlocked pa... |
1422 1423 |
* try_to_unmap_file - unmap/unlock file page using the object-based rmap method * @page: the page to unmap/unlock |
14fa31b89 HWPOISON: Use bit... |
1424 |
* @flags: action and flags |
1da177e4c Linux-2.6.12-rc2 |
1425 1426 1427 1428 |
* * Find all the mappings of a page using the mapping pointer and the vma chains * contained in the address_space struct it points to. * |
b291f0003 mlock: mlocked pa... |
1429 1430 1431 1432 1433 1434 |
* This function is only called from try_to_unmap/try_to_munlock for * object-based pages. * When called from try_to_munlock(), the mmap_sem of the mm containing the vma * where the page was found will be held for write. So, we won't recheck * vm_flags for that VMA. That should be OK, because that vma shouldn't be * 'LOCKED. |
1da177e4c Linux-2.6.12-rc2 |
1435 |
*/ |
14fa31b89 HWPOISON: Use bit... |
1436 |
static int try_to_unmap_file(struct page *page, enum ttu_flags flags) |
1da177e4c Linux-2.6.12-rc2 |
1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 |
{ struct address_space *mapping = page->mapping; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); struct vm_area_struct *vma; struct prio_tree_iter iter; int ret = SWAP_AGAIN; unsigned long cursor; unsigned long max_nl_cursor = 0; unsigned long max_nl_size = 0; unsigned int mapcount; |
3d48ae45e mm: Convert i_mma... |
1447 |
mutex_lock(&mapping->i_mmap_mutex); |
1da177e4c Linux-2.6.12-rc2 |
1448 |
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { |
1cb1729b1 mm: pass address ... |
1449 1450 1451 1452 |
unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; ret = try_to_unmap_one(page, vma, address, flags); |
53f79acb6 mm: mlocking in t... |
1453 1454 |
if (ret != SWAP_AGAIN || !page_mapped(page)) goto out; |
1da177e4c Linux-2.6.12-rc2 |
1455 1456 1457 1458 |
} if (list_empty(&mapping->i_mmap_nonlinear)) goto out; |
53f79acb6 mm: mlocking in t... |
1459 1460 1461 1462 1463 1464 1465 |
/* * We don't bother to try to find the munlocked page in nonlinears. * It's costly. Instead, later, page reclaim logic may call * try_to_unmap(TTU_MUNLOCK) and recover PG_mlocked lazily. */ if (TTU_ACTION(flags) == TTU_MUNLOCK) goto out; |
1da177e4c Linux-2.6.12-rc2 |
1466 1467 |
list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { |
1da177e4c Linux-2.6.12-rc2 |
1468 1469 1470 1471 1472 1473 1474 |
cursor = (unsigned long) vma->vm_private_data; if (cursor > max_nl_cursor) max_nl_cursor = cursor; cursor = vma->vm_end - vma->vm_start; if (cursor > max_nl_size) max_nl_size = cursor; } |
b291f0003 mlock: mlocked pa... |
1475 |
if (max_nl_size == 0) { /* all nonlinears locked or reserved ? */ |
1da177e4c Linux-2.6.12-rc2 |
1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 |
ret = SWAP_FAIL; goto out; } /* * We don't try to search for this page in the nonlinear vmas, * and page_referenced wouldn't have found it anyway. Instead * just walk the nonlinear vmas trying to age and unmap some. * The mapcount of the page we came in with is irrelevant, * but even so use it as a guide to how hard we should try? */ mapcount = page_mapcount(page); if (!mapcount) goto out; |
3d48ae45e mm: Convert i_mma... |
1490 |
cond_resched(); |
1da177e4c Linux-2.6.12-rc2 |
1491 1492 1493 1494 1495 1496 1497 1498 |
max_nl_size = (max_nl_size + CLUSTER_SIZE - 1) & CLUSTER_MASK; if (max_nl_cursor == 0) max_nl_cursor = CLUSTER_SIZE; do { list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { |
1da177e4c Linux-2.6.12-rc2 |
1499 |
cursor = (unsigned long) vma->vm_private_data; |
839b9685e [PATCH] rmap: don... |
1500 |
while ( cursor < max_nl_cursor && |
1da177e4c Linux-2.6.12-rc2 |
1501 |
cursor < vma->vm_end - vma->vm_start) { |
53f79acb6 mm: mlocking in t... |
1502 1503 1504 |
if (try_to_unmap_cluster(cursor, &mapcount, vma, page) == SWAP_MLOCK) ret = SWAP_MLOCK; |
1da177e4c Linux-2.6.12-rc2 |
1505 1506 1507 1508 1509 1510 1511 |
cursor += CLUSTER_SIZE; vma->vm_private_data = (void *) cursor; if ((int)mapcount <= 0) goto out; } vma->vm_private_data = (void *) max_nl_cursor; } |
3d48ae45e mm: Convert i_mma... |
1512 |
cond_resched(); |
1da177e4c Linux-2.6.12-rc2 |
1513 1514 1515 1516 1517 1518 1519 1520 |
max_nl_cursor += CLUSTER_SIZE; } while (max_nl_cursor <= max_nl_size); /* * Don't loop forever (perhaps all the remaining pages are * in locked vmas). Reset cursor on all unreserved nonlinear * vmas, now forgetting on which ones it had fallen behind. */ |
101d2be76 [PATCH] unpaged: ... |
1521 1522 |
list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) vma->vm_private_data = NULL; |
1da177e4c Linux-2.6.12-rc2 |
1523 |
out: |
3d48ae45e mm: Convert i_mma... |
1524 |
mutex_unlock(&mapping->i_mmap_mutex); |
1da177e4c Linux-2.6.12-rc2 |
1525 1526 1527 1528 1529 1530 |
return ret; } /** * try_to_unmap - try to remove all page table mappings to a page * @page: the page to get unmapped |
14fa31b89 HWPOISON: Use bit... |
1531 |
* @flags: action and flags |
1da177e4c Linux-2.6.12-rc2 |
1532 1533 1534 1535 1536 1537 1538 1539 |
* * Tries to remove all the page table entries which are mapping this * page, used in the pageout path. Caller must hold the page lock. * Return values are: * * SWAP_SUCCESS - we succeeded in removing all mappings * SWAP_AGAIN - we missed a mapping, try again later * SWAP_FAIL - the page is unswappable |
b291f0003 mlock: mlocked pa... |
1540 |
* SWAP_MLOCK - page is mlocked. |
1da177e4c Linux-2.6.12-rc2 |
1541 |
*/ |
14fa31b89 HWPOISON: Use bit... |
1542 |
int try_to_unmap(struct page *page, enum ttu_flags flags) |
1da177e4c Linux-2.6.12-rc2 |
1543 1544 |
{ int ret; |
1da177e4c Linux-2.6.12-rc2 |
1545 |
BUG_ON(!PageLocked(page)); |
91600e9e5 thp: fix memory-f... |
1546 |
VM_BUG_ON(!PageHuge(page) && PageTransHuge(page)); |
1da177e4c Linux-2.6.12-rc2 |
1547 |
|
5ad646880 ksm: let shared p... |
1548 1549 1550 |
if (unlikely(PageKsm(page))) ret = try_to_unmap_ksm(page, flags); else if (PageAnon(page)) |
14fa31b89 HWPOISON: Use bit... |
1551 |
ret = try_to_unmap_anon(page, flags); |
1da177e4c Linux-2.6.12-rc2 |
1552 |
else |
14fa31b89 HWPOISON: Use bit... |
1553 |
ret = try_to_unmap_file(page, flags); |
b291f0003 mlock: mlocked pa... |
1554 |
if (ret != SWAP_MLOCK && !page_mapped(page)) |
1da177e4c Linux-2.6.12-rc2 |
1555 1556 1557 |
ret = SWAP_SUCCESS; return ret; } |
81b4082dc [PATCH] mm: rmap.... |
1558 |
|
b291f0003 mlock: mlocked pa... |
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 |
/** * try_to_munlock - try to munlock a page * @page: the page to be munlocked * * Called from munlock code. Checks all of the VMAs mapping the page * to make sure nobody else has this page mlocked. The page will be * returned with PG_mlocked cleared if no other vmas have it mlocked. * * Return values are: * |
53f79acb6 mm: mlocking in t... |
1569 |
* SWAP_AGAIN - no vma is holding page mlocked, or, |
b291f0003 mlock: mlocked pa... |
1570 |
* SWAP_AGAIN - page mapped in mlocked vma -- couldn't acquire mmap sem |
5ad646880 ksm: let shared p... |
1571 |
* SWAP_FAIL - page cannot be located at present |
b291f0003 mlock: mlocked pa... |
1572 1573 1574 1575 1576 |
* SWAP_MLOCK - page is now mlocked. */ int try_to_munlock(struct page *page) { VM_BUG_ON(!PageLocked(page) || PageLRU(page)); |
5ad646880 ksm: let shared p... |
1577 1578 1579 |
if (unlikely(PageKsm(page))) return try_to_unmap_ksm(page, TTU_MUNLOCK); else if (PageAnon(page)) |
14fa31b89 HWPOISON: Use bit... |
1580 |
return try_to_unmap_anon(page, TTU_MUNLOCK); |
b291f0003 mlock: mlocked pa... |
1581 |
else |
14fa31b89 HWPOISON: Use bit... |
1582 |
return try_to_unmap_file(page, TTU_MUNLOCK); |
b291f0003 mlock: mlocked pa... |
1583 |
} |
e9995ef97 ksm: rmap_walk to... |
1584 |
|
01d8b20de mm: simplify anon... |
1585 |
void __put_anon_vma(struct anon_vma *anon_vma) |
76545066c mm: extend KSM re... |
1586 |
{ |
01d8b20de mm: simplify anon... |
1587 |
struct anon_vma *root = anon_vma->root; |
76545066c mm: extend KSM re... |
1588 |
|
01d8b20de mm: simplify anon... |
1589 1590 |
if (root != anon_vma && atomic_dec_and_test(&root->refcount)) anon_vma_free(root); |
76545066c mm: extend KSM re... |
1591 |
|
01d8b20de mm: simplify anon... |
1592 |
anon_vma_free(anon_vma); |
76545066c mm: extend KSM re... |
1593 |
} |
76545066c mm: extend KSM re... |
1594 |
|
e9995ef97 ksm: rmap_walk to... |
1595 1596 1597 1598 1599 1600 1601 1602 1603 |
#ifdef CONFIG_MIGRATION /* * rmap_walk() and its helpers rmap_walk_anon() and rmap_walk_file(): * Called by migrate.c to remove migration ptes, but might be used more later. */ static int rmap_walk_anon(struct page *page, int (*rmap_one)(struct page *, struct vm_area_struct *, unsigned long, void *), void *arg) { struct anon_vma *anon_vma; |
5beb49305 mm: change anon_v... |
1604 |
struct anon_vma_chain *avc; |
e9995ef97 ksm: rmap_walk to... |
1605 1606 1607 1608 1609 |
int ret = SWAP_AGAIN; /* * Note: remove_migration_ptes() cannot use page_lock_anon_vma() * because that depends on page_mapped(); but not all its usages |
3f6c82728 mm: migration: ta... |
1610 1611 |
* are holding mmap_sem. Users without mmap_sem are required to * take a reference count to prevent the anon_vma disappearing |
e9995ef97 ksm: rmap_walk to... |
1612 1613 1614 1615 |
*/ anon_vma = page_anon_vma(page); if (!anon_vma) return ret; |
cba48b98f mm: change direct... |
1616 |
anon_vma_lock(anon_vma); |
5beb49305 mm: change anon_v... |
1617 1618 |
list_for_each_entry(avc, &anon_vma->head, same_anon_vma) { struct vm_area_struct *vma = avc->vma; |
e9995ef97 ksm: rmap_walk to... |
1619 1620 1621 1622 1623 1624 1625 |
unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; ret = rmap_one(page, vma, address, arg); if (ret != SWAP_AGAIN) break; } |
cba48b98f mm: change direct... |
1626 |
anon_vma_unlock(anon_vma); |
e9995ef97 ksm: rmap_walk to... |
1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 |
return ret; } static int rmap_walk_file(struct page *page, int (*rmap_one)(struct page *, struct vm_area_struct *, unsigned long, void *), void *arg) { struct address_space *mapping = page->mapping; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); struct vm_area_struct *vma; struct prio_tree_iter iter; int ret = SWAP_AGAIN; if (!mapping) return ret; |
3d48ae45e mm: Convert i_mma... |
1641 |
mutex_lock(&mapping->i_mmap_mutex); |
e9995ef97 ksm: rmap_walk to... |
1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 |
vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { unsigned long address = vma_address(page, vma); if (address == -EFAULT) continue; ret = rmap_one(page, vma, address, arg); if (ret != SWAP_AGAIN) break; } /* * No nonlinear handling: being always shared, nonlinear vmas * never contain migration ptes. Decide what to do about this * limitation to linear when we need rmap_walk() on nonlinear. */ |
3d48ae45e mm: Convert i_mma... |
1655 |
mutex_unlock(&mapping->i_mmap_mutex); |
e9995ef97 ksm: rmap_walk to... |
1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 |
return ret; } int rmap_walk(struct page *page, int (*rmap_one)(struct page *, struct vm_area_struct *, unsigned long, void *), void *arg) { VM_BUG_ON(!PageLocked(page)); if (unlikely(PageKsm(page))) return rmap_walk_ksm(page, rmap_one, arg); else if (PageAnon(page)) return rmap_walk_anon(page, rmap_one, arg); else return rmap_walk_file(page, rmap_one, arg); } #endif /* CONFIG_MIGRATION */ |
0fe6e20b9 hugetlb, rmap: ad... |
1672 |
|
e3390f67a hwpoison: rename ... |
1673 |
#ifdef CONFIG_HUGETLB_PAGE |
0fe6e20b9 hugetlb, rmap: ad... |
1674 1675 1676 1677 1678 1679 1680 1681 1682 |
/* * The following three functions are for anonymous (private mapped) hugepages. * Unlike common anonymous pages, anonymous hugepages have no accounting code * and no lru code, because we handle hugepages differently from common pages. */ static void __hugepage_set_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address, int exclusive) { struct anon_vma *anon_vma = vma->anon_vma; |
433abed6c hugetlb, rmap: al... |
1683 |
|
0fe6e20b9 hugetlb, rmap: ad... |
1684 |
BUG_ON(!anon_vma); |
433abed6c hugetlb, rmap: al... |
1685 1686 1687 1688 1689 |
if (PageAnon(page)) return; if (!exclusive) anon_vma = anon_vma->root; |
0fe6e20b9 hugetlb, rmap: ad... |
1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 |
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; page->mapping = (struct address_space *) anon_vma; page->index = linear_page_index(vma, address); } void hugepage_add_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { struct anon_vma *anon_vma = vma->anon_vma; int first; |
a850ea303 hugetlb, rmap: ad... |
1700 1701 |
BUG_ON(!PageLocked(page)); |
0fe6e20b9 hugetlb, rmap: ad... |
1702 |
BUG_ON(!anon_vma); |
5dbe0af47 mm: fix kernel BU... |
1703 |
/* address might be in next vma when migration races vma_adjust */ |
0fe6e20b9 hugetlb, rmap: ad... |
1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 |
first = atomic_inc_and_test(&page->_mapcount); if (first) __hugepage_set_anon_rmap(page, vma, address, 0); } void hugepage_add_new_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { BUG_ON(address < vma->vm_start || address >= vma->vm_end); atomic_set(&page->_mapcount, 0); __hugepage_set_anon_rmap(page, vma, address, 1); } |
e3390f67a hwpoison: rename ... |
1716 |
#endif /* CONFIG_HUGETLB_PAGE */ |