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mm/rmap.c
54 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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* hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) * mapping->i_mmap_rwsem * anon_vma->rwsem * mm->page_table_lock or pte_lock |
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* zone_lru_lock (in mark_page_accessed, isolate_lru_page) |
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* swap_lock (in swap_duplicate, swap_info_get) * mmlist_lock (in mmput, drain_mmlist and others) * mapping->private_lock (in __set_page_dirty_buffers) * mem_cgroup_{begin,end}_page_stat (memcg->move_lock) |
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* i_pages lock (widely used) |
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* inode->i_lock (in set_page_dirty's __mark_inode_dirty) * bdi.wb->list_lock (in set_page_dirty's __mark_inode_dirty) * sb_lock (within inode_lock in fs/fs-writeback.c) |
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* i_pages lock (widely used, in set_page_dirty, |
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* in arch-dependent flush_dcache_mmap_lock, * within bdi.wb->list_lock in __sync_single_inode) |
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* |
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* anon_vma->rwsem,mapping->i_mutex (memory_failure, collect_procs_anon) |
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* ->tasklist_lock |
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* pte map lock |
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*/ #include <linux/mm.h> |
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#include <linux/sched/mm.h> |
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#include <linux/sched/task.h> |
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#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 <linux/backing-dev.h> |
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#include <linux/page_idle.h> |
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#include <linux/memremap.h> |
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#include <linux/userfaultfd_k.h> |
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#include <asm/tlbflush.h> |
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#include <trace/events/tlb.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); |
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anon_vma->degree = 1; /* Reference for first vma */ anon_vma->parent = anon_vma; |
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/* * 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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/* |
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* Synchronize against page_lock_anon_vma_read() such that |
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* 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 |
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* down_read_trylock() from page_lock_anon_vma_read(). This orders: |
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* |
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* page_lock_anon_vma_read() VS put_anon_vma() * down_read_trylock() atomic_dec_and_test() |
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* LOCK MB |
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* atomic_read() rwsem_is_locked() |
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* * LOCK should suffice since the actual taking of the lock must * happen _before_ what follows. */ |
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might_sleep(); |
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if (rwsem_is_locked(&anon_vma->root->rwsem)) { |
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anon_vma_lock_write(anon_vma); |
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anon_vma_unlock_write(anon_vma); |
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} |
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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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static void anon_vma_chain_link(struct vm_area_struct *vma, struct anon_vma_chain *avc, struct anon_vma *anon_vma) { avc->vma = vma; avc->anon_vma = anon_vma; list_add(&avc->same_vma, &vma->anon_vma_chain); |
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anon_vma_interval_tree_insert(avc, &anon_vma->rb_root); |
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} |
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/** |
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* __anon_vma_prepare - attach an anon_vma to a memory region |
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* @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. * |
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* The common case will be that we already have one, which * is handled inline by anon_vma_prepare(). 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 |
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* optimistically looked up an anon_vma in page_lock_anon_vma_read() |
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* 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) |
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{ |
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struct mm_struct *mm = vma->vm_mm; struct anon_vma *anon_vma, *allocated; |
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struct anon_vma_chain *avc; |
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might_sleep(); |
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|
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avc = anon_vma_chain_alloc(GFP_KERNEL); if (!avc) goto out_enomem; anon_vma = find_mergeable_anon_vma(vma); allocated = NULL; if (!anon_vma) { anon_vma = anon_vma_alloc(); if (unlikely(!anon_vma)) goto out_enomem_free_avc; allocated = anon_vma; } |
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|
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anon_vma_lock_write(anon_vma); /* page_table_lock to protect against threads */ spin_lock(&mm->page_table_lock); if (likely(!vma->anon_vma)) { vma->anon_vma = anon_vma; anon_vma_chain_link(vma, avc, anon_vma); /* vma reference or self-parent link for new root */ anon_vma->degree++; |
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allocated = NULL; |
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avc = NULL; } spin_unlock(&mm->page_table_lock); anon_vma_unlock_write(anon_vma); |
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|
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if (unlikely(allocated)) put_anon_vma(allocated); if (unlikely(avc)) anon_vma_chain_free(avc); |
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|
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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)) |
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up_write(&root->rwsem); |
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root = new_root; |
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down_write(&root->rwsem); |
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} return root; } static inline void unlock_anon_vma_root(struct anon_vma *root) { if (root) |
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up_write(&root->rwsem); |
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} |
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/* * Attach the anon_vmas from src to dst. * Returns 0 on success, -ENOMEM on failure. |
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* * If dst->anon_vma is NULL this function tries to find and reuse existing * anon_vma which has no vmas and only one child anon_vma. This prevents * degradation of anon_vma hierarchy to endless linear chain in case of * constantly forking task. On the other hand, an anon_vma with more than one * child isn't reused even if there was no alive vma, thus rmap walker has a * good chance of avoiding scanning the whole hierarchy when it searches where * page is mapped. |
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*/ 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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/* * Reuse existing anon_vma if its degree lower than two, * that means it has no vma and only one anon_vma child. * * Do not chose parent anon_vma, otherwise first child * will always reuse it. Root anon_vma is never reused: * it has self-parent reference and at least one child. */ if (!dst->anon_vma && anon_vma != src->anon_vma && anon_vma->degree < 2) dst->anon_vma = anon_vma; |
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} |
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if (dst->anon_vma) dst->anon_vma->degree++; |
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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: |
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/* * dst->anon_vma is dropped here otherwise its degree can be incorrectly * decremented in unlink_anon_vmas(). * We can safely do this because callers of anon_vma_clone() don't care * about dst->anon_vma if anon_vma_clone() failed. */ dst->anon_vma = NULL; |
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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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int error; |
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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; |
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/* Drop inherited anon_vma, we'll reuse existing or allocate new. */ vma->anon_vma = NULL; |
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/* * First, attach the new VMA to the parent VMA's anon_vmas, * so rmap can find non-COWed pages in child processes. */ |
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error = anon_vma_clone(vma, pvma); if (error) return error; |
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|
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/* An existing anon_vma has been reused, all done then. */ if (vma->anon_vma) return 0; |
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/* 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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anon_vma->parent = pvma->anon_vma; |
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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_write(anon_vma); |
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anon_vma_chain_link(vma, avc, anon_vma); |
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anon_vma->parent->degree++; |
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anon_vma_unlock_write(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); |
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anon_vma_interval_tree_remove(avc, &anon_vma->rb_root); |
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/* * Leave empty anon_vmas on the list - we'll need * to free them outside the lock. */ |
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if (RB_EMPTY_ROOT(&anon_vma->rb_root.rb_root)) { |
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anon_vma->parent->degree--; |
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continue; |
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} |
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list_del(&avc->same_vma); anon_vma_chain_free(avc); } |
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if (vma->anon_vma) vma->anon_vma->degree--; |
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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() |
5a505085f mm/rmap: Convert ... |
394 |
* needing to write-acquire the anon_vma->root->rwsem. |
eee2acbae mm: avoid repeate... |
395 396 397 |
*/ list_for_each_entry_safe(avc, next, &vma->anon_vma_chain, same_vma) { struct anon_vma *anon_vma = avc->anon_vma; |
e4c5800a3 mm/rmap: replace ... |
398 |
VM_WARN_ON(anon_vma->degree); |
eee2acbae mm: avoid repeate... |
399 |
put_anon_vma(anon_vma); |
5beb49305 mm: change anon_v... |
400 401 402 403 |
list_del(&avc->same_vma); anon_vma_chain_free(avc); } } |
51cc50685 SL*B: drop kmem c... |
404 |
static void anon_vma_ctor(void *data) |
1da177e4c Linux-2.6.12-rc2 |
405 |
{ |
a35afb830 Remove SLAB_CTOR_... |
406 |
struct anon_vma *anon_vma = data; |
1da177e4c Linux-2.6.12-rc2 |
407 |
|
5a505085f mm/rmap: Convert ... |
408 |
init_rwsem(&anon_vma->rwsem); |
83813267c mm: move anon_vma... |
409 |
atomic_set(&anon_vma->refcount, 0); |
f808c13fd lib/interval_tree... |
410 |
anon_vma->rb_root = RB_ROOT_CACHED; |
1da177e4c Linux-2.6.12-rc2 |
411 412 413 414 415 |
} void __init anon_vma_init(void) { anon_vma_cachep = kmem_cache_create("anon_vma", sizeof(struct anon_vma), |
5f0d5a3ae mm: Rename SLAB_D... |
416 |
0, SLAB_TYPESAFE_BY_RCU|SLAB_PANIC|SLAB_ACCOUNT, |
5d097056c kmemcg: account c... |
417 418 419 |
anon_vma_ctor); anon_vma_chain_cachep = KMEM_CACHE(anon_vma_chain, SLAB_PANIC|SLAB_ACCOUNT); |
1da177e4c Linux-2.6.12-rc2 |
420 421 422 |
} /* |
6111e4ca6 mm: improve page_... |
423 424 425 426 427 428 429 430 431 |
* 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). * |
bc658c960 mm, rmap: Add yet... |
432 433 434 435 436 |
* 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 ]. * |
6111e4ca6 mm: improve page_... |
437 438 439 440 441 442 443 |
* 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. |
1da177e4c Linux-2.6.12-rc2 |
444 |
*/ |
746b18d42 mm: use refcounts... |
445 |
struct anon_vma *page_get_anon_vma(struct page *page) |
1da177e4c Linux-2.6.12-rc2 |
446 |
{ |
746b18d42 mm: use refcounts... |
447 |
struct anon_vma *anon_vma = NULL; |
1da177e4c Linux-2.6.12-rc2 |
448 449 450 |
unsigned long anon_mapping; rcu_read_lock(); |
4db0c3c29 mm: remove rest o... |
451 |
anon_mapping = (unsigned long)READ_ONCE(page->mapping); |
3ca7b3c5b mm: define PAGE_M... |
452 |
if ((anon_mapping & PAGE_MAPPING_FLAGS) != PAGE_MAPPING_ANON) |
1da177e4c Linux-2.6.12-rc2 |
453 454 455 456 457 |
goto out; if (!page_mapped(page)) goto out; anon_vma = (struct anon_vma *) (anon_mapping - PAGE_MAPPING_ANON); |
746b18d42 mm: use refcounts... |
458 459 460 461 |
if (!atomic_inc_not_zero(&anon_vma->refcount)) { anon_vma = NULL; goto out; } |
f18194275 mm: fix hang on a... |
462 463 464 |
/* * If this page is still mapped, then its anon_vma cannot have been |
746b18d42 mm: use refcounts... |
465 466 |
* freed. But if it has been unmapped, we have no security against the * anon_vma structure being freed and reused (for another anon_vma: |
5f0d5a3ae mm: Rename SLAB_D... |
467 |
* SLAB_TYPESAFE_BY_RCU guarantees that - so the atomic_inc_not_zero() |
746b18d42 mm: use refcounts... |
468 |
* above cannot corrupt). |
f18194275 mm: fix hang on a... |
469 |
*/ |
746b18d42 mm: use refcounts... |
470 |
if (!page_mapped(page)) { |
7f39dda9d mm: fix sleeping ... |
471 |
rcu_read_unlock(); |
746b18d42 mm: use refcounts... |
472 |
put_anon_vma(anon_vma); |
7f39dda9d mm: fix sleeping ... |
473 |
return NULL; |
746b18d42 mm: use refcounts... |
474 |
} |
1da177e4c Linux-2.6.12-rc2 |
475 476 |
out: rcu_read_unlock(); |
746b18d42 mm: use refcounts... |
477 478 479 |
return anon_vma; } |
88c22088b mm: optimize page... |
480 481 482 483 484 485 486 |
/* * 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. */ |
4fc3f1d66 mm/rmap, migratio... |
487 |
struct anon_vma *page_lock_anon_vma_read(struct page *page) |
746b18d42 mm: use refcounts... |
488 |
{ |
88c22088b mm: optimize page... |
489 |
struct anon_vma *anon_vma = NULL; |
eee0f252c mm: fix page_lock... |
490 |
struct anon_vma *root_anon_vma; |
88c22088b mm: optimize page... |
491 |
unsigned long anon_mapping; |
746b18d42 mm: use refcounts... |
492 |
|
88c22088b mm: optimize page... |
493 |
rcu_read_lock(); |
4db0c3c29 mm: remove rest o... |
494 |
anon_mapping = (unsigned long)READ_ONCE(page->mapping); |
88c22088b mm: optimize page... |
495 496 497 498 499 500 |
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); |
4db0c3c29 mm: remove rest o... |
501 |
root_anon_vma = READ_ONCE(anon_vma->root); |
4fc3f1d66 mm/rmap, migratio... |
502 |
if (down_read_trylock(&root_anon_vma->rwsem)) { |
88c22088b mm: optimize page... |
503 |
/* |
eee0f252c mm: fix page_lock... |
504 505 |
* 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... |
506 |
* not go away, see anon_vma_free(). |
88c22088b mm: optimize page... |
507 |
*/ |
eee0f252c mm: fix page_lock... |
508 |
if (!page_mapped(page)) { |
4fc3f1d66 mm/rmap, migratio... |
509 |
up_read(&root_anon_vma->rwsem); |
88c22088b mm: optimize page... |
510 511 512 513 |
anon_vma = NULL; } goto out; } |
746b18d42 mm: use refcounts... |
514 |
|
88c22088b mm: optimize page... |
515 516 517 518 519 520 521 |
/* trylock failed, we got to sleep */ if (!atomic_inc_not_zero(&anon_vma->refcount)) { anon_vma = NULL; goto out; } if (!page_mapped(page)) { |
7f39dda9d mm: fix sleeping ... |
522 |
rcu_read_unlock(); |
88c22088b mm: optimize page... |
523 |
put_anon_vma(anon_vma); |
7f39dda9d mm: fix sleeping ... |
524 |
return NULL; |
88c22088b mm: optimize page... |
525 526 527 528 |
} /* we pinned the anon_vma, its safe to sleep */ rcu_read_unlock(); |
4fc3f1d66 mm/rmap, migratio... |
529 |
anon_vma_lock_read(anon_vma); |
88c22088b mm: optimize page... |
530 531 532 533 534 |
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 |
4fc3f1d66 mm/rmap, migratio... |
535 |
* we'll deadlock on the anon_vma_lock_write() recursion. |
88c22088b mm: optimize page... |
536 |
*/ |
4fc3f1d66 mm/rmap, migratio... |
537 |
anon_vma_unlock_read(anon_vma); |
88c22088b mm: optimize page... |
538 539 540 541 542 543 544 545 |
__put_anon_vma(anon_vma); anon_vma = NULL; } return anon_vma; out: rcu_read_unlock(); |
746b18d42 mm: use refcounts... |
546 |
return anon_vma; |
34bbd7040 [PATCH] adapt pag... |
547 |
} |
4fc3f1d66 mm/rmap, migratio... |
548 |
void page_unlock_anon_vma_read(struct anon_vma *anon_vma) |
34bbd7040 [PATCH] adapt pag... |
549 |
{ |
4fc3f1d66 mm/rmap, migratio... |
550 |
anon_vma_unlock_read(anon_vma); |
1da177e4c Linux-2.6.12-rc2 |
551 |
} |
72b252aed mm: send one IPI ... |
552 |
#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH |
72b252aed mm: send one IPI ... |
553 554 555 556 557 558 559 560 561 |
/* * Flush TLB entries for recently unmapped pages from remote CPUs. It is * important if a PTE was dirty when it was unmapped that it's flushed * before any IO is initiated on the page to prevent lost writes. Similarly, * it must be flushed before freeing to prevent data leakage. */ void try_to_unmap_flush(void) { struct tlbflush_unmap_batch *tlb_ubc = ¤t->tlb_ubc; |
72b252aed mm: send one IPI ... |
562 563 564 |
if (!tlb_ubc->flush_required) return; |
e73ad5ff2 mm, x86/mm: Make ... |
565 |
arch_tlbbatch_flush(&tlb_ubc->arch); |
72b252aed mm: send one IPI ... |
566 |
tlb_ubc->flush_required = false; |
d950c9477 mm: defer flush o... |
567 |
tlb_ubc->writable = false; |
72b252aed mm: send one IPI ... |
568 |
} |
d950c9477 mm: defer flush o... |
569 570 571 572 573 574 575 576 |
/* Flush iff there are potentially writable TLB entries that can race with IO */ void try_to_unmap_flush_dirty(void) { struct tlbflush_unmap_batch *tlb_ubc = ¤t->tlb_ubc; if (tlb_ubc->writable) try_to_unmap_flush(); } |
c7ab0d2fd mm: convert try_t... |
577 |
static void set_tlb_ubc_flush_pending(struct mm_struct *mm, bool writable) |
72b252aed mm: send one IPI ... |
578 579 |
{ struct tlbflush_unmap_batch *tlb_ubc = ¤t->tlb_ubc; |
e73ad5ff2 mm, x86/mm: Make ... |
580 |
arch_tlbbatch_add_mm(&tlb_ubc->arch, mm); |
72b252aed mm: send one IPI ... |
581 |
tlb_ubc->flush_required = true; |
d950c9477 mm: defer flush o... |
582 583 |
/* |
3ea277194 mm, mprotect: flu... |
584 585 586 587 588 589 590 |
* Ensure compiler does not re-order the setting of tlb_flush_batched * before the PTE is cleared. */ barrier(); mm->tlb_flush_batched = true; /* |
d950c9477 mm: defer flush o... |
591 592 593 594 595 596 |
* If the PTE was dirty then it's best to assume it's writable. The * caller must use try_to_unmap_flush_dirty() or try_to_unmap_flush() * before the page is queued for IO. */ if (writable) tlb_ubc->writable = true; |
72b252aed mm: send one IPI ... |
597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 |
} /* * Returns true if the TLB flush should be deferred to the end of a batch of * unmap operations to reduce IPIs. */ static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags) { bool should_defer = false; if (!(flags & TTU_BATCH_FLUSH)) return false; /* If remote CPUs need to be flushed then defer batch the flush */ if (cpumask_any_but(mm_cpumask(mm), get_cpu()) < nr_cpu_ids) should_defer = true; put_cpu(); return should_defer; } |
3ea277194 mm, mprotect: flu... |
617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 |
/* * Reclaim unmaps pages under the PTL but do not flush the TLB prior to * releasing the PTL if TLB flushes are batched. It's possible for a parallel * operation such as mprotect or munmap to race between reclaim unmapping * the page and flushing the page. If this race occurs, it potentially allows * access to data via a stale TLB entry. Tracking all mm's that have TLB * batching in flight would be expensive during reclaim so instead track * whether TLB batching occurred in the past and if so then do a flush here * if required. This will cost one additional flush per reclaim cycle paid * by the first operation at risk such as mprotect and mumap. * * This must be called under the PTL so that an access to tlb_flush_batched * that is potentially a "reclaim vs mprotect/munmap/etc" race will synchronise * via the PTL. */ void flush_tlb_batched_pending(struct mm_struct *mm) { if (mm->tlb_flush_batched) { flush_tlb_mm(mm); /* * Do not allow the compiler to re-order the clearing of * tlb_flush_batched before the tlb is flushed. */ barrier(); mm->tlb_flush_batched = false; } } |
72b252aed mm: send one IPI ... |
646 |
#else |
c7ab0d2fd mm: convert try_t... |
647 |
static void set_tlb_ubc_flush_pending(struct mm_struct *mm, bool writable) |
72b252aed mm: send one IPI ... |
648 649 650 651 652 653 654 655 |
{ } static bool should_defer_flush(struct mm_struct *mm, enum ttu_flags flags) { return false; } #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */ |
1da177e4c Linux-2.6.12-rc2 |
656 |
/* |
bf89c8c86 mm/rmap.c: fix co... |
657 |
* At what user virtual address is page expected in vma? |
ab941e0ff rmap: remove anon... |
658 |
* Caller should check the page is actually part of the vma. |
1da177e4c Linux-2.6.12-rc2 |
659 660 661 |
*/ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) { |
86c2ad199 mm rmap: remove v... |
662 |
unsigned long address; |
21d0d443c rmap: resurrect p... |
663 |
if (PageAnon(page)) { |
4829b906c ksm: fix page_add... |
664 665 666 667 668 669 670 |
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... |
671 |
return -EFAULT; |
27ba0644e rmap: drop suppor... |
672 673 |
} else if (page->mapping) { if (!vma->vm_file || vma->vm_file->f_mapping != page->mapping) |
1da177e4c Linux-2.6.12-rc2 |
674 675 676 |
return -EFAULT; } else return -EFAULT; |
86c2ad199 mm rmap: remove v... |
677 678 679 680 |
address = __vma_address(page, vma); if (unlikely(address < vma->vm_start || address >= vma->vm_end)) return -EFAULT; return address; |
1da177e4c Linux-2.6.12-rc2 |
681 |
} |
6219049ae mm: introduce mm_... |
682 683 684 |
pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address) { pgd_t *pgd; |
c2febafc6 mm: convert gener... |
685 |
p4d_t *p4d; |
6219049ae mm: introduce mm_... |
686 687 |
pud_t *pud; pmd_t *pmd = NULL; |
f72e7dcdd mm: let mm_find_p... |
688 |
pmd_t pmde; |
6219049ae mm: introduce mm_... |
689 690 691 692 |
pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) goto out; |
c2febafc6 mm: convert gener... |
693 694 695 696 697 |
p4d = p4d_offset(pgd, address); if (!p4d_present(*p4d)) goto out; pud = pud_offset(p4d, address); |
6219049ae mm: introduce mm_... |
698 699 700 701 |
if (!pud_present(*pud)) goto out; pmd = pmd_offset(pud, address); |
f72e7dcdd mm: let mm_find_p... |
702 |
/* |
8809aa2d2 mm: clarify that ... |
703 |
* Some THP functions use the sequence pmdp_huge_clear_flush(), set_pmd_at() |
f72e7dcdd mm: let mm_find_p... |
704 705 706 |
* without holding anon_vma lock for write. So when looking for a * genuine pmde (in which to find pte), test present and !THP together. */ |
e37c69827 mm: replace ACCES... |
707 708 |
pmde = *pmd; barrier(); |
f72e7dcdd mm: let mm_find_p... |
709 |
if (!pmd_present(pmde) || pmd_trans_huge(pmde)) |
6219049ae mm: introduce mm_... |
710 711 712 713 |
pmd = NULL; out: return pmd; } |
8749cfea1 mm: add page_chec... |
714 715 716 717 718 719 720 721 722 |
struct page_referenced_arg { int mapcount; int referenced; unsigned long vm_flags; struct mem_cgroup *memcg; }; /* * arg: page_referenced_arg will be passed */ |
e4b822227 mm: make rmap_one... |
723 |
static bool page_referenced_one(struct page *page, struct vm_area_struct *vma, |
8749cfea1 mm: add page_chec... |
724 725 |
unsigned long address, void *arg) { |
8749cfea1 mm: add page_chec... |
726 |
struct page_referenced_arg *pra = arg; |
8eaedede8 mm: fix handling ... |
727 728 729 730 731 |
struct page_vma_mapped_walk pvmw = { .page = page, .vma = vma, .address = address, }; |
8749cfea1 mm: add page_chec... |
732 |
int referenced = 0; |
8eaedede8 mm: fix handling ... |
733 734 |
while (page_vma_mapped_walk(&pvmw)) { address = pvmw.address; |
b20ce5e03 mm: prepare page_... |
735 |
|
8eaedede8 mm: fix handling ... |
736 737 738 |
if (vma->vm_flags & VM_LOCKED) { page_vma_mapped_walk_done(&pvmw); pra->vm_flags |= VM_LOCKED; |
e4b822227 mm: make rmap_one... |
739 |
return false; /* To break the loop */ |
8eaedede8 mm: fix handling ... |
740 |
} |
71e3aac07 thp: transparent ... |
741 |
|
8eaedede8 mm: fix handling ... |
742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 |
if (pvmw.pte) { if (ptep_clear_flush_young_notify(vma, address, pvmw.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(!(vma->vm_flags & VM_SEQ_READ))) referenced++; } } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { if (pmdp_clear_flush_young_notify(vma, address, pvmw.pmd)) |
8749cfea1 mm: add page_chec... |
759 |
referenced++; |
8eaedede8 mm: fix handling ... |
760 761 762 |
} else { /* unexpected pmd-mapped page? */ WARN_ON_ONCE(1); |
8749cfea1 mm: add page_chec... |
763 |
} |
8eaedede8 mm: fix handling ... |
764 765 |
pra->mapcount--; |
b20ce5e03 mm: prepare page_... |
766 |
} |
b20ce5e03 mm: prepare page_... |
767 |
|
33c3fc71c mm: introduce idl... |
768 769 770 771 |
if (referenced) clear_page_idle(page); if (test_and_clear_page_young(page)) referenced++; |
9f32624be mm/rmap: use rmap... |
772 773 774 |
if (referenced) { pra->referenced++; pra->vm_flags |= vma->vm_flags; |
1da177e4c Linux-2.6.12-rc2 |
775 |
} |
34bbd7040 [PATCH] adapt pag... |
776 |
|
9f32624be mm/rmap: use rmap... |
777 |
if (!pra->mapcount) |
e4b822227 mm: make rmap_one... |
778 |
return false; /* To break the loop */ |
9f32624be mm/rmap: use rmap... |
779 |
|
e4b822227 mm: make rmap_one... |
780 |
return true; |
1da177e4c Linux-2.6.12-rc2 |
781 |
} |
9f32624be mm/rmap: use rmap... |
782 |
static bool invalid_page_referenced_vma(struct vm_area_struct *vma, void *arg) |
1da177e4c Linux-2.6.12-rc2 |
783 |
{ |
9f32624be mm/rmap: use rmap... |
784 785 |
struct page_referenced_arg *pra = arg; struct mem_cgroup *memcg = pra->memcg; |
1da177e4c Linux-2.6.12-rc2 |
786 |
|
9f32624be mm/rmap: use rmap... |
787 788 |
if (!mm_match_cgroup(vma->vm_mm, memcg)) return true; |
1da177e4c Linux-2.6.12-rc2 |
789 |
|
9f32624be mm/rmap: use rmap... |
790 |
return false; |
1da177e4c Linux-2.6.12-rc2 |
791 792 793 794 795 796 |
} /** * page_referenced - test if the page was referenced * @page: the page to test * @is_locked: caller holds lock on the page |
72835c86c mm: unify remaini... |
797 |
* @memcg: target memory cgroup |
6fe6b7e35 vmscan: report vm... |
798 |
* @vm_flags: collect encountered vma->vm_flags who actually referenced the page |
1da177e4c Linux-2.6.12-rc2 |
799 800 801 802 |
* * Quick test_and_clear_referenced for all mappings to a page, * returns the number of ptes which referenced the page. */ |
6fe6b7e35 vmscan: report vm... |
803 804 |
int page_referenced(struct page *page, int is_locked, |
72835c86c mm: unify remaini... |
805 |
struct mem_cgroup *memcg, |
6fe6b7e35 vmscan: report vm... |
806 |
unsigned long *vm_flags) |
1da177e4c Linux-2.6.12-rc2 |
807 |
{ |
5ad646880 ksm: let shared p... |
808 |
int we_locked = 0; |
9f32624be mm/rmap: use rmap... |
809 |
struct page_referenced_arg pra = { |
b20ce5e03 mm: prepare page_... |
810 |
.mapcount = total_mapcount(page), |
9f32624be mm/rmap: use rmap... |
811 812 813 814 815 816 817 |
.memcg = memcg, }; struct rmap_walk_control rwc = { .rmap_one = page_referenced_one, .arg = (void *)&pra, .anon_lock = page_lock_anon_vma_read, }; |
1da177e4c Linux-2.6.12-rc2 |
818 |
|
6fe6b7e35 vmscan: report vm... |
819 |
*vm_flags = 0; |
9f32624be mm/rmap: use rmap... |
820 821 822 823 824 825 826 827 828 829 |
if (!page_mapped(page)) return 0; if (!page_rmapping(page)) return 0; if (!is_locked && (!PageAnon(page) || PageKsm(page))) { we_locked = trylock_page(page); if (!we_locked) return 1; |
1da177e4c Linux-2.6.12-rc2 |
830 |
} |
9f32624be mm/rmap: use rmap... |
831 832 833 834 835 836 837 838 839 |
/* * If we are reclaiming on behalf of a cgroup, skip * counting on behalf of references from different * cgroups */ if (memcg) { rwc.invalid_vma = invalid_page_referenced_vma; } |
c24f386c6 mm: remove unnces... |
840 |
rmap_walk(page, &rwc); |
9f32624be mm/rmap: use rmap... |
841 842 843 844 845 846 |
*vm_flags = pra.vm_flags; if (we_locked) unlock_page(page); return pra.referenced; |
1da177e4c Linux-2.6.12-rc2 |
847 |
} |
e4b822227 mm: make rmap_one... |
848 |
static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma, |
9853a407b mm/rmap: use rmap... |
849 |
unsigned long address, void *arg) |
d08b3851d [PATCH] mm: track... |
850 |
{ |
f27176cfc mm: convert page_... |
851 852 853 854 855 856 |
struct page_vma_mapped_walk pvmw = { .page = page, .vma = vma, .address = address, .flags = PVMW_SYNC, }; |
369ea8242 mm/rmap: update t... |
857 |
unsigned long start = address, end; |
9853a407b mm/rmap: use rmap... |
858 |
int *cleaned = arg; |
d08b3851d [PATCH] mm: track... |
859 |
|
369ea8242 mm/rmap: update t... |
860 861 862 863 864 865 |
/* * We have to assume the worse case ie pmd for invalidation. Note that * the page can not be free from this function. */ end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); |
f27176cfc mm: convert page_... |
866 |
while (page_vma_mapped_walk(&pvmw)) { |
cdb07bdea mm/rmap.c: remove... |
867 |
unsigned long cstart; |
f27176cfc mm: convert page_... |
868 |
int ret = 0; |
369ea8242 mm/rmap: update t... |
869 870 |
cstart = address = pvmw.address; |
f27176cfc mm: convert page_... |
871 872 873 874 875 876 |
if (pvmw.pte) { pte_t entry; pte_t *pte = pvmw.pte; if (!pte_dirty(*pte) && !pte_write(*pte)) continue; |
785373b4c Revert "rmap: do ... |
877 878 |
flush_cache_page(vma, address, pte_pfn(*pte)); entry = ptep_clear_flush(vma, address, pte); |
f27176cfc mm: convert page_... |
879 880 |
entry = pte_wrprotect(entry); entry = pte_mkclean(entry); |
785373b4c Revert "rmap: do ... |
881 |
set_pte_at(vma->vm_mm, address, pte, entry); |
f27176cfc mm: convert page_... |
882 883 884 885 886 887 888 889 |
ret = 1; } else { #ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE pmd_t *pmd = pvmw.pmd; pmd_t entry; if (!pmd_dirty(*pmd) && !pmd_write(*pmd)) continue; |
785373b4c Revert "rmap: do ... |
890 891 |
flush_cache_page(vma, address, page_to_pfn(page)); entry = pmdp_huge_clear_flush(vma, address, pmd); |
f27176cfc mm: convert page_... |
892 893 |
entry = pmd_wrprotect(entry); entry = pmd_mkclean(entry); |
785373b4c Revert "rmap: do ... |
894 |
set_pmd_at(vma->vm_mm, address, pmd, entry); |
369ea8242 mm/rmap: update t... |
895 |
cstart &= PMD_MASK; |
f27176cfc mm: convert page_... |
896 897 898 899 900 901 |
ret = 1; #else /* unexpected pmd-mapped page? */ WARN_ON_ONCE(1); #endif } |
d08b3851d [PATCH] mm: track... |
902 |
|
0f10851ea mm/mmu_notifier: ... |
903 904 905 906 907 |
/* * No need to call mmu_notifier_invalidate_range() as we are * downgrading page table protection not changing it to point * to a new page. * |
ad56b738c docs/vm: rename d... |
908 |
* See Documentation/vm/mmu_notifier.rst |
0f10851ea mm/mmu_notifier: ... |
909 910 |
*/ if (ret) |
f27176cfc mm: convert page_... |
911 |
(*cleaned)++; |
c2fda5fed [PATCH] Fix up pa... |
912 |
} |
d08b3851d [PATCH] mm: track... |
913 |
|
369ea8242 mm/rmap: update t... |
914 |
mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); |
e4b822227 mm: make rmap_one... |
915 |
return true; |
d08b3851d [PATCH] mm: track... |
916 |
} |
9853a407b mm/rmap: use rmap... |
917 |
static bool invalid_mkclean_vma(struct vm_area_struct *vma, void *arg) |
d08b3851d [PATCH] mm: track... |
918 |
{ |
9853a407b mm/rmap: use rmap... |
919 |
if (vma->vm_flags & VM_SHARED) |
871beb8c3 mm/rmap: fix cocc... |
920 |
return false; |
d08b3851d [PATCH] mm: track... |
921 |
|
871beb8c3 mm/rmap: fix cocc... |
922 |
return true; |
d08b3851d [PATCH] mm: track... |
923 924 925 926 |
} int page_mkclean(struct page *page) { |
9853a407b mm/rmap: use rmap... |
927 928 929 930 931 932 933 |
int cleaned = 0; struct address_space *mapping; struct rmap_walk_control rwc = { .arg = (void *)&cleaned, .rmap_one = page_mkclean_one, .invalid_vma = invalid_mkclean_vma, }; |
d08b3851d [PATCH] mm: track... |
934 935 |
BUG_ON(!PageLocked(page)); |
9853a407b mm/rmap: use rmap... |
936 937 938 939 940 941 942 943 |
if (!page_mapped(page)) return 0; mapping = page_mapping(page); if (!mapping) return 0; rmap_walk(page, &rwc); |
d08b3851d [PATCH] mm: track... |
944 |
|
9853a407b mm/rmap: use rmap... |
945 |
return cleaned; |
d08b3851d [PATCH] mm: track... |
946 |
} |
60b59beaf fbdev: mm: Deferr... |
947 |
EXPORT_SYMBOL_GPL(page_mkclean); |
d08b3851d [PATCH] mm: track... |
948 |
|
1da177e4c Linux-2.6.12-rc2 |
949 |
/** |
c44b67432 rmap: move exclus... |
950 951 952 |
* 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 |
c44b67432 rmap: move exclus... |
953 954 955 956 957 958 |
* * 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. */ |
5a49973d7 mm: thp: refix fa... |
959 |
void page_move_anon_rmap(struct page *page, struct vm_area_struct *vma) |
c44b67432 rmap: move exclus... |
960 961 |
{ struct anon_vma *anon_vma = vma->anon_vma; |
5a49973d7 mm: thp: refix fa... |
962 |
page = compound_head(page); |
309381fea mm: dump page whe... |
963 |
VM_BUG_ON_PAGE(!PageLocked(page), page); |
81d1b09c6 mm: convert a few... |
964 |
VM_BUG_ON_VMA(!anon_vma, vma); |
c44b67432 rmap: move exclus... |
965 966 |
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; |
414e2fb8c rmap: fix theoret... |
967 968 969 970 971 972 |
/* * Ensure that anon_vma and the PAGE_MAPPING_ANON bit are written * simultaneously, so a concurrent reader (eg page_referenced()'s * PageAnon()) will not see one without the other. */ WRITE_ONCE(page->mapping, (struct address_space *) anon_vma); |
c44b67432 rmap: move exclus... |
973 974 975 |
} /** |
4e1c19750 Clean up __page_s... |
976 977 978 979 |
* __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... |
980 |
* @exclusive: the page is exclusively owned by the current process |
9617d95e6 [PATCH] mm: rmap ... |
981 982 |
*/ static void __page_set_anon_rmap(struct page *page, |
e8a03feb5 rmap: add exclusi... |
983 |
struct vm_area_struct *vma, unsigned long address, int exclusive) |
9617d95e6 [PATCH] mm: rmap ... |
984 |
{ |
e8a03feb5 rmap: add exclusi... |
985 |
struct anon_vma *anon_vma = vma->anon_vma; |
ea90002b0 anonvma: when set... |
986 |
|
e8a03feb5 rmap: add exclusi... |
987 |
BUG_ON(!anon_vma); |
ea90002b0 anonvma: when set... |
988 |
|
4e1c19750 Clean up __page_s... |
989 990 |
if (PageAnon(page)) return; |
ea90002b0 anonvma: when set... |
991 |
/* |
e8a03feb5 rmap: add exclusi... |
992 993 994 |
* 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... |
995 |
*/ |
4e1c19750 Clean up __page_s... |
996 |
if (!exclusive) |
288468c33 rmap: always use ... |
997 |
anon_vma = anon_vma->root; |
9617d95e6 [PATCH] mm: rmap ... |
998 |
|
9617d95e6 [PATCH] mm: rmap ... |
999 1000 |
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; page->mapping = (struct address_space *) anon_vma; |
9617d95e6 [PATCH] mm: rmap ... |
1001 |
page->index = linear_page_index(vma, address); |
9617d95e6 [PATCH] mm: rmap ... |
1002 1003 1004 |
} /** |
43d8eac44 mm: rmap kernel-d... |
1005 |
* __page_check_anon_rmap - sanity check anonymous rmap addition |
c97a9e10e mm: more rmap che... |
1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 |
* @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... |
1026 |
BUG_ON(page_anon_vma(page)->root != vma->anon_vma->root); |
53f9263ba mm: rework mapcou... |
1027 |
BUG_ON(page_to_pgoff(page) != linear_page_index(vma, address)); |
c97a9e10e mm: more rmap che... |
1028 1029 1030 1031 |
#endif } /** |
1da177e4c Linux-2.6.12-rc2 |
1032 1033 1034 1035 |
* 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 |
d281ee614 rmap: add argumen... |
1036 |
* @compound: charge the page as compound or small page |
1da177e4c Linux-2.6.12-rc2 |
1037 |
* |
5ad646880 ksm: let shared p... |
1038 |
* The caller needs to hold the pte lock, and the page must be locked in |
80e148226 ksm: share anon p... |
1039 1040 1041 |
* 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 |
1042 1043 |
*/ void page_add_anon_rmap(struct page *page, |
d281ee614 rmap: add argumen... |
1044 |
struct vm_area_struct *vma, unsigned long address, bool compound) |
1da177e4c Linux-2.6.12-rc2 |
1045 |
{ |
d281ee614 rmap: add argumen... |
1046 |
do_page_add_anon_rmap(page, vma, address, compound ? RMAP_COMPOUND : 0); |
ad8c2ee80 rmap: add exclusi... |
1047 1048 1049 1050 1051 1052 1053 1054 |
} /* * 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, |
d281ee614 rmap: add argumen... |
1055 |
struct vm_area_struct *vma, unsigned long address, int flags) |
ad8c2ee80 rmap: add exclusi... |
1056 |
{ |
53f9263ba mm: rework mapcou... |
1057 1058 |
bool compound = flags & RMAP_COMPOUND; bool first; |
e9b61f198 thp: reintroduce ... |
1059 1060 |
if (compound) { atomic_t *mapcount; |
53f9263ba mm: rework mapcou... |
1061 |
VM_BUG_ON_PAGE(!PageLocked(page), page); |
e9b61f198 thp: reintroduce ... |
1062 1063 1064 |
VM_BUG_ON_PAGE(!PageTransHuge(page), page); mapcount = compound_mapcount_ptr(page); first = atomic_inc_and_test(mapcount); |
53f9263ba mm: rework mapcou... |
1065 1066 1067 |
} else { first = atomic_inc_and_test(&page->_mapcount); } |
79134171d thp: transparent ... |
1068 |
if (first) { |
d281ee614 rmap: add argumen... |
1069 |
int nr = compound ? hpage_nr_pages(page) : 1; |
bea04b073 mm: use the light... |
1070 1071 1072 1073 1074 1075 |
/* * We use the irq-unsafe __{inc|mod}_zone_page_stat because * these counters are not modified in interrupt context, and * pte lock(a spinlock) is held, which implies preemption * disabled. */ |
65c453778 mm, rmap: account... |
1076 |
if (compound) |
11fb99898 mm: move most fil... |
1077 |
__inc_node_page_state(page, NR_ANON_THPS); |
4b9d0fab7 mm: rename NR_ANO... |
1078 |
__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, nr); |
79134171d thp: transparent ... |
1079 |
} |
5ad646880 ksm: let shared p... |
1080 1081 |
if (unlikely(PageKsm(page))) return; |
309381fea mm: dump page whe... |
1082 |
VM_BUG_ON_PAGE(!PageLocked(page), page); |
53f9263ba mm: rework mapcou... |
1083 |
|
5dbe0af47 mm: fix kernel BU... |
1084 |
/* address might be in next vma when migration races vma_adjust */ |
5ad646880 ksm: let shared p... |
1085 |
if (first) |
d281ee614 rmap: add argumen... |
1086 1087 |
__page_set_anon_rmap(page, vma, address, flags & RMAP_EXCLUSIVE); |
69029cd55 memcg: remove ref... |
1088 |
else |
c97a9e10e mm: more rmap che... |
1089 |
__page_check_anon_rmap(page, vma, address); |
1da177e4c Linux-2.6.12-rc2 |
1090 |
} |
43d8eac44 mm: rmap kernel-d... |
1091 |
/** |
9617d95e6 [PATCH] mm: rmap ... |
1092 1093 1094 1095 |
* 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 |
d281ee614 rmap: add argumen... |
1096 |
* @compound: charge the page as compound or small page |
9617d95e6 [PATCH] mm: rmap ... |
1097 1098 1099 |
* * 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... |
1100 |
* Page does not have to be locked. |
9617d95e6 [PATCH] mm: rmap ... |
1101 1102 |
*/ void page_add_new_anon_rmap(struct page *page, |
d281ee614 rmap: add argumen... |
1103 |
struct vm_area_struct *vma, unsigned long address, bool compound) |
9617d95e6 [PATCH] mm: rmap ... |
1104 |
{ |
d281ee614 rmap: add argumen... |
1105 |
int nr = compound ? hpage_nr_pages(page) : 1; |
81d1b09c6 mm: convert a few... |
1106 |
VM_BUG_ON_VMA(address < vma->vm_start || address >= vma->vm_end, vma); |
fa9949da5 mm: use __SetPage... |
1107 |
__SetPageSwapBacked(page); |
d281ee614 rmap: add argumen... |
1108 1109 |
if (compound) { VM_BUG_ON_PAGE(!PageTransHuge(page), page); |
53f9263ba mm: rework mapcou... |
1110 1111 |
/* increment count (starts at -1) */ atomic_set(compound_mapcount_ptr(page), 0); |
11fb99898 mm: move most fil... |
1112 |
__inc_node_page_state(page, NR_ANON_THPS); |
53f9263ba mm: rework mapcou... |
1113 1114 1115 1116 1117 |
} else { /* Anon THP always mapped first with PMD */ VM_BUG_ON_PAGE(PageTransCompound(page), page); /* increment count (starts at -1) */ atomic_set(&page->_mapcount, 0); |
d281ee614 rmap: add argumen... |
1118 |
} |
4b9d0fab7 mm: rename NR_ANO... |
1119 |
__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, nr); |
e8a03feb5 rmap: add exclusi... |
1120 |
__page_set_anon_rmap(page, vma, address, 1); |
9617d95e6 [PATCH] mm: rmap ... |
1121 |
} |
1da177e4c Linux-2.6.12-rc2 |
1122 1123 1124 |
/** * page_add_file_rmap - add pte mapping to a file page * @page: the page to add the mapping to |
e8b098fc5 mm: kernel-doc: a... |
1125 |
* @compound: charge the page as compound or small page |
1da177e4c Linux-2.6.12-rc2 |
1126 |
* |
b8072f099 [PATCH] mm: updat... |
1127 |
* The caller needs to hold the pte lock. |
1da177e4c Linux-2.6.12-rc2 |
1128 |
*/ |
dd78fedde rmap: support fil... |
1129 |
void page_add_file_rmap(struct page *page, bool compound) |
1da177e4c Linux-2.6.12-rc2 |
1130 |
{ |
dd78fedde rmap: support fil... |
1131 1132 1133 |
int i, nr = 1; VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page); |
62cccb8c8 mm: simplify lock... |
1134 |
lock_page_memcg(page); |
dd78fedde rmap: support fil... |
1135 1136 1137 1138 1139 1140 1141 |
if (compound && PageTransHuge(page)) { for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { if (atomic_inc_and_test(&page[i]._mapcount)) nr++; } if (!atomic_inc_and_test(compound_mapcount_ptr(page))) goto out; |
65c453778 mm, rmap: account... |
1142 |
VM_BUG_ON_PAGE(!PageSwapBacked(page), page); |
11fb99898 mm: move most fil... |
1143 |
__inc_node_page_state(page, NR_SHMEM_PMDMAPPED); |
dd78fedde rmap: support fil... |
1144 |
} else { |
c8efc390c mm, rmap: fix fal... |
1145 1146 |
if (PageTransCompound(page) && page_mapping(page)) { VM_WARN_ON_ONCE(!PageLocked(page)); |
9a73f61bd thp, mlock: do no... |
1147 1148 1149 1150 |
SetPageDoubleMap(compound_head(page)); if (PageMlocked(page)) clear_page_mlock(compound_head(page)); } |
dd78fedde rmap: support fil... |
1151 1152 |
if (!atomic_inc_and_test(&page->_mapcount)) goto out; |
d69b042f3 memcg: add file-b... |
1153 |
} |
00f3ca2c2 mm: memcontrol: p... |
1154 |
__mod_lruvec_page_state(page, NR_FILE_MAPPED, nr); |
dd78fedde rmap: support fil... |
1155 |
out: |
62cccb8c8 mm: simplify lock... |
1156 |
unlock_page_memcg(page); |
1da177e4c Linux-2.6.12-rc2 |
1157 |
} |
dd78fedde rmap: support fil... |
1158 |
static void page_remove_file_rmap(struct page *page, bool compound) |
8186eb6a7 mm: rmap: split o... |
1159 |
{ |
dd78fedde rmap: support fil... |
1160 |
int i, nr = 1; |
57dea93ac rmap: fix compoun... |
1161 |
VM_BUG_ON_PAGE(compound && !PageHead(page), page); |
62cccb8c8 mm: simplify lock... |
1162 |
lock_page_memcg(page); |
8186eb6a7 mm: rmap: split o... |
1163 |
|
53f9263ba mm: rework mapcou... |
1164 1165 1166 1167 |
/* Hugepages are not counted in NR_FILE_MAPPED for now. */ if (unlikely(PageHuge(page))) { /* hugetlb pages are always mapped with pmds */ atomic_dec(compound_mapcount_ptr(page)); |
8186eb6a7 mm: rmap: split o... |
1168 |
goto out; |
53f9263ba mm: rework mapcou... |
1169 |
} |
8186eb6a7 mm: rmap: split o... |
1170 |
|
53f9263ba mm: rework mapcou... |
1171 |
/* page still mapped by someone else? */ |
dd78fedde rmap: support fil... |
1172 1173 1174 1175 1176 1177 1178 |
if (compound && PageTransHuge(page)) { for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { if (atomic_add_negative(-1, &page[i]._mapcount)) nr++; } if (!atomic_add_negative(-1, compound_mapcount_ptr(page))) goto out; |
65c453778 mm, rmap: account... |
1179 |
VM_BUG_ON_PAGE(!PageSwapBacked(page), page); |
11fb99898 mm: move most fil... |
1180 |
__dec_node_page_state(page, NR_SHMEM_PMDMAPPED); |
dd78fedde rmap: support fil... |
1181 1182 1183 1184 |
} else { if (!atomic_add_negative(-1, &page->_mapcount)) goto out; } |
8186eb6a7 mm: rmap: split o... |
1185 1186 |
/* |
00f3ca2c2 mm: memcontrol: p... |
1187 |
* We use the irq-unsafe __{inc|mod}_lruvec_page_state because |
8186eb6a7 mm: rmap: split o... |
1188 1189 1190 |
* these counters are not modified in interrupt context, and * pte lock(a spinlock) is held, which implies preemption disabled. */ |
00f3ca2c2 mm: memcontrol: p... |
1191 |
__mod_lruvec_page_state(page, NR_FILE_MAPPED, -nr); |
8186eb6a7 mm: rmap: split o... |
1192 1193 1194 1195 |
if (unlikely(PageMlocked(page))) clear_page_mlock(page); out: |
62cccb8c8 mm: simplify lock... |
1196 |
unlock_page_memcg(page); |
8186eb6a7 mm: rmap: split o... |
1197 |
} |
53f9263ba mm: rework mapcou... |
1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 |
static void page_remove_anon_compound_rmap(struct page *page) { int i, nr; if (!atomic_add_negative(-1, compound_mapcount_ptr(page))) return; /* Hugepages are not counted in NR_ANON_PAGES for now. */ if (unlikely(PageHuge(page))) return; if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) return; |
11fb99898 mm: move most fil... |
1211 |
__dec_node_page_state(page, NR_ANON_THPS); |
53f9263ba mm: rework mapcou... |
1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 |
if (TestClearPageDoubleMap(page)) { /* * Subpages can be mapped with PTEs too. Check how many of * themi are still mapped. */ for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) { if (atomic_add_negative(-1, &page[i]._mapcount)) nr++; } } else { nr = HPAGE_PMD_NR; } |
e90309c9f thp: allow mlocke... |
1225 1226 |
if (unlikely(PageMlocked(page))) clear_page_mlock(page); |
9a982250f thp: introduce de... |
1227 |
if (nr) { |
4b9d0fab7 mm: rename NR_ANO... |
1228 |
__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, -nr); |
9a982250f thp: introduce de... |
1229 1230 |
deferred_split_huge_page(page); } |
53f9263ba mm: rework mapcou... |
1231 |
} |
1da177e4c Linux-2.6.12-rc2 |
1232 1233 |
/** * page_remove_rmap - take down pte mapping from a page |
d281ee614 rmap: add argumen... |
1234 1235 |
* @page: page to remove mapping from * @compound: uncharge the page as compound or small page |
1da177e4c Linux-2.6.12-rc2 |
1236 |
* |
b8072f099 [PATCH] mm: updat... |
1237 |
* The caller needs to hold the pte lock. |
1da177e4c Linux-2.6.12-rc2 |
1238 |
*/ |
d281ee614 rmap: add argumen... |
1239 |
void page_remove_rmap(struct page *page, bool compound) |
1da177e4c Linux-2.6.12-rc2 |
1240 |
{ |
dd78fedde rmap: support fil... |
1241 1242 |
if (!PageAnon(page)) return page_remove_file_rmap(page, compound); |
89c06bd52 memcg: use new lo... |
1243 |
|
53f9263ba mm: rework mapcou... |
1244 1245 |
if (compound) return page_remove_anon_compound_rmap(page); |
b904dcfed mm: clean up page... |
1246 1247 |
/* page still mapped by someone else? */ if (!atomic_add_negative(-1, &page->_mapcount)) |
8186eb6a7 mm: rmap: split o... |
1248 |
return; |
b904dcfed mm: clean up page... |
1249 |
/* |
bea04b073 mm: use the light... |
1250 1251 |
* We use the irq-unsafe __{inc|mod}_zone_page_stat because * these counters are not modified in interrupt context, and |
bea04b073 mm: use the light... |
1252 |
* pte lock(a spinlock) is held, which implies preemption disabled. |
0fe6e20b9 hugetlb, rmap: ad... |
1253 |
*/ |
4b9d0fab7 mm: rename NR_ANO... |
1254 |
__dec_node_page_state(page, NR_ANON_MAPPED); |
8186eb6a7 mm: rmap: split o... |
1255 |
|
e6c509f85 mm: use clear_pag... |
1256 1257 |
if (unlikely(PageMlocked(page))) clear_page_mlock(page); |
8186eb6a7 mm: rmap: split o... |
1258 |
|
9a982250f thp: introduce de... |
1259 1260 |
if (PageTransCompound(page)) deferred_split_huge_page(compound_head(page)); |
b904dcfed mm: clean up page... |
1261 1262 1263 1264 |
/* * 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 |
2d4894b5d mm: remove cold p... |
1265 |
* before us: so leave the reset to free_unref_page, |
b904dcfed mm: clean up page... |
1266 1267 1268 1269 |
* 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 |
1270 1271 1272 |
} /* |
526295064 mm/rmap: use rmap... |
1273 |
* @arg: enum ttu_flags will be passed to this argument |
1da177e4c Linux-2.6.12-rc2 |
1274 |
*/ |
e4b822227 mm: make rmap_one... |
1275 |
static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, |
526295064 mm/rmap: use rmap... |
1276 |
unsigned long address, void *arg) |
1da177e4c Linux-2.6.12-rc2 |
1277 1278 |
{ struct mm_struct *mm = vma->vm_mm; |
c7ab0d2fd mm: convert try_t... |
1279 1280 1281 1282 1283 |
struct page_vma_mapped_walk pvmw = { .page = page, .vma = vma, .address = address, }; |
1da177e4c Linux-2.6.12-rc2 |
1284 |
pte_t pteval; |
c7ab0d2fd mm: convert try_t... |
1285 |
struct page *subpage; |
785373b4c Revert "rmap: do ... |
1286 |
bool ret = true; |
369ea8242 mm/rmap: update t... |
1287 |
unsigned long start = address, end; |
802a3a92a mm: reclaim MADV_... |
1288 |
enum ttu_flags flags = (enum ttu_flags)arg; |
1da177e4c Linux-2.6.12-rc2 |
1289 |
|
b87537d9e mm: rmap use pte ... |
1290 1291 |
/* munlock has nothing to gain from examining un-locked vmas */ if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED)) |
e4b822227 mm: make rmap_one... |
1292 |
return true; |
b87537d9e mm: rmap use pte ... |
1293 |
|
a5430dda8 mm/migrate: suppo... |
1294 1295 1296 |
if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION) && is_zone_device_page(page) && !is_device_private_page(page)) return true; |
fec89c109 thp: rewrite free... |
1297 1298 |
if (flags & TTU_SPLIT_HUGE_PMD) { split_huge_pmd_address(vma, address, |
b5ff8161e mm: thp: introduc... |
1299 |
flags & TTU_SPLIT_FREEZE, page); |
fec89c109 thp: rewrite free... |
1300 |
} |
369ea8242 mm/rmap: update t... |
1301 |
/* |
017b1660d mm: migration: fi... |
1302 1303 1304 1305 1306 1307 |
* For THP, we have to assume the worse case ie pmd for invalidation. * For hugetlb, it could be much worse if we need to do pud * invalidation in the case of pmd sharing. * * Note that the page can not be free in this function as call of * try_to_unmap() must hold a reference on the page. |
369ea8242 mm/rmap: update t... |
1308 1309 |
*/ end = min(vma->vm_end, start + (PAGE_SIZE << compound_order(page))); |
017b1660d mm: migration: fi... |
1310 1311 1312 1313 1314 1315 1316 |
if (PageHuge(page)) { /* * If sharing is possible, start and end will be adjusted * accordingly. */ adjust_range_if_pmd_sharing_possible(vma, &start, &end); } |
369ea8242 mm/rmap: update t... |
1317 |
mmu_notifier_invalidate_range_start(vma->vm_mm, start, end); |
c7ab0d2fd mm: convert try_t... |
1318 |
while (page_vma_mapped_walk(&pvmw)) { |
616b83715 mm: thp: enable t... |
1319 1320 1321 1322 |
#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION /* PMD-mapped THP migration entry */ if (!pvmw.pte && (flags & TTU_MIGRATION)) { VM_BUG_ON_PAGE(PageHuge(page) || !PageTransCompound(page), page); |
616b83715 mm: thp: enable t... |
1323 1324 1325 1326 |
set_pmd_migration_entry(&pvmw, page); continue; } #endif |
c7ab0d2fd mm: convert try_t... |
1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 |
/* * 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. */ if (!(flags & TTU_IGNORE_MLOCK)) { if (vma->vm_flags & VM_LOCKED) { /* PTE-mapped THP are never mlocked */ if (!PageTransCompound(page)) { /* * Holding pte lock, we do *not* need * mmap_sem here */ mlock_vma_page(page); } |
e4b822227 mm: make rmap_one... |
1342 |
ret = false; |
c7ab0d2fd mm: convert try_t... |
1343 1344 |
page_vma_mapped_walk_done(&pvmw); break; |
9a73f61bd thp, mlock: do no... |
1345 |
} |
c7ab0d2fd mm: convert try_t... |
1346 1347 |
if (flags & TTU_MUNLOCK) continue; |
b87537d9e mm: rmap use pte ... |
1348 |
} |
c7ab0d2fd mm: convert try_t... |
1349 |
|
8346242a7 rmap: fix NULL-po... |
1350 1351 1352 1353 |
/* Unexpected PMD-mapped THP? */ VM_BUG_ON_PAGE(!pvmw.pte, page); subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte); |
785373b4c Revert "rmap: do ... |
1354 |
address = pvmw.address; |
017b1660d mm: migration: fi... |
1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 |
if (PageHuge(page)) { if (huge_pmd_unshare(mm, &address, pvmw.pte)) { /* * huge_pmd_unshare unmapped an entire PMD * page. There is no way of knowing exactly * which PMDs may be cached for this mm, so * we must flush them all. start/end were * already adjusted above to cover this range. */ flush_cache_range(vma, start, end); flush_tlb_range(vma, start, end); mmu_notifier_invalidate_range(mm, start, end); /* * The ref count of the PMD page was dropped * which is part of the way map counting * is done for shared PMDs. Return 'true' * here. When there is no other sharing, * huge_pmd_unshare returns false and we will * unmap the actual page and drop map count * to zero. */ page_vma_mapped_walk_done(&pvmw); break; } } |
8346242a7 rmap: fix NULL-po... |
1381 |
|
a5430dda8 mm/migrate: suppo... |
1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 |
if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION) && is_zone_device_page(page)) { swp_entry_t entry; pte_t swp_pte; pteval = ptep_get_and_clear(mm, pvmw.address, pvmw.pte); /* * 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. */ entry = make_migration_entry(page, 0); swp_pte = swp_entry_to_pte(entry); if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); set_pte_at(mm, pvmw.address, pvmw.pte, swp_pte); |
0f10851ea mm/mmu_notifier: ... |
1400 1401 1402 1403 |
/* * No need to invalidate here it will synchronize on * against the special swap migration pte. */ |
a5430dda8 mm/migrate: suppo... |
1404 1405 |
goto discard; } |
c7ab0d2fd mm: convert try_t... |
1406 |
if (!(flags & TTU_IGNORE_ACCESS)) { |
785373b4c Revert "rmap: do ... |
1407 |
if (ptep_clear_flush_young_notify(vma, address, |
c7ab0d2fd mm: convert try_t... |
1408 |
pvmw.pte)) { |
e4b822227 mm: make rmap_one... |
1409 |
ret = false; |
c7ab0d2fd mm: convert try_t... |
1410 1411 1412 |
page_vma_mapped_walk_done(&pvmw); break; } |
b291f0003 mlock: mlocked pa... |
1413 |
} |
1da177e4c Linux-2.6.12-rc2 |
1414 |
|
c7ab0d2fd mm: convert try_t... |
1415 |
/* Nuke the page table entry. */ |
785373b4c Revert "rmap: do ... |
1416 |
flush_cache_page(vma, address, pte_pfn(*pvmw.pte)); |
c7ab0d2fd mm: convert try_t... |
1417 1418 1419 1420 1421 1422 1423 1424 1425 |
if (should_defer_flush(mm, flags)) { /* * We clear the PTE but do not flush so potentially * a remote CPU could still be writing to the page. * If the entry was previously clean then the * architecture must guarantee that a clear->dirty * transition on a cached TLB entry is written through * and traps if the PTE is unmapped. */ |
785373b4c Revert "rmap: do ... |
1426 |
pteval = ptep_get_and_clear(mm, address, pvmw.pte); |
c7ab0d2fd mm: convert try_t... |
1427 1428 1429 |
set_tlb_ubc_flush_pending(mm, pte_dirty(pteval)); } else { |
785373b4c Revert "rmap: do ... |
1430 |
pteval = ptep_clear_flush(vma, address, pvmw.pte); |
c7ab0d2fd mm: convert try_t... |
1431 |
} |
72b252aed mm: send one IPI ... |
1432 |
|
c7ab0d2fd mm: convert try_t... |
1433 1434 1435 |
/* Move the dirty bit to the page. Now the pte is gone. */ if (pte_dirty(pteval)) set_page_dirty(page); |
1da177e4c Linux-2.6.12-rc2 |
1436 |
|
c7ab0d2fd mm: convert try_t... |
1437 1438 |
/* Update high watermark before we lower rss */ update_hiwater_rss(mm); |
1da177e4c Linux-2.6.12-rc2 |
1439 |
|
c7ab0d2fd mm: convert try_t... |
1440 |
if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) { |
5fd27b8e7 mm: rmap: use cor... |
1441 |
pteval = swp_entry_to_pte(make_hwpoison_entry(subpage)); |
c7ab0d2fd mm: convert try_t... |
1442 1443 1444 |
if (PageHuge(page)) { int nr = 1 << compound_order(page); hugetlb_count_sub(nr, mm); |
785373b4c Revert "rmap: do ... |
1445 |
set_huge_swap_pte_at(mm, address, |
5fd27b8e7 mm: rmap: use cor... |
1446 1447 |
pvmw.pte, pteval, vma_mmu_pagesize(vma)); |
c7ab0d2fd mm: convert try_t... |
1448 1449 |
} else { dec_mm_counter(mm, mm_counter(page)); |
785373b4c Revert "rmap: do ... |
1450 |
set_pte_at(mm, address, pvmw.pte, pteval); |
c7ab0d2fd mm: convert try_t... |
1451 |
} |
365e9c87a [PATCH] mm: updat... |
1452 |
|
bce73e484 mm: do not drop u... |
1453 |
} else if (pte_unused(pteval) && !userfaultfd_armed(vma)) { |
c7ab0d2fd mm: convert try_t... |
1454 1455 1456 1457 |
/* * The guest indicated that the page content is of no * interest anymore. Simply discard the pte, vmscan * will take care of the rest. |
bce73e484 mm: do not drop u... |
1458 1459 1460 1461 1462 |
* A future reference will then fault in a new zero * page. When userfaultfd is active, we must not drop * this page though, as its main user (postcopy * migration) will not expect userfaults on already * copied pages. |
c7ab0d2fd mm: convert try_t... |
1463 |
*/ |
eca56ff90 mm, shmem: add in... |
1464 |
dec_mm_counter(mm, mm_counter(page)); |
0f10851ea mm/mmu_notifier: ... |
1465 1466 1467 |
/* We have to invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); |
c7ab0d2fd mm: convert try_t... |
1468 |
} else if (IS_ENABLED(CONFIG_MIGRATION) && |
b5ff8161e mm: thp: introduc... |
1469 |
(flags & (TTU_MIGRATION|TTU_SPLIT_FREEZE))) { |
c7ab0d2fd mm: convert try_t... |
1470 1471 |
swp_entry_t entry; pte_t swp_pte; |
ca827d55e mm, swap: Add inf... |
1472 1473 1474 1475 1476 1477 1478 |
if (arch_unmap_one(mm, vma, address, pteval) < 0) { set_pte_at(mm, address, pvmw.pte, pteval); ret = false; page_vma_mapped_walk_done(&pvmw); break; } |
c7ab0d2fd mm: convert try_t... |
1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 |
/* * 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. */ entry = make_migration_entry(subpage, pte_write(pteval)); swp_pte = swp_entry_to_pte(entry); if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); |
785373b4c Revert "rmap: do ... |
1489 |
set_pte_at(mm, address, pvmw.pte, swp_pte); |
0f10851ea mm/mmu_notifier: ... |
1490 1491 1492 1493 |
/* * No need to invalidate here it will synchronize on * against the special swap migration pte. */ |
c7ab0d2fd mm: convert try_t... |
1494 1495 1496 1497 1498 1499 1500 |
} else if (PageAnon(page)) { swp_entry_t entry = { .val = page_private(subpage) }; pte_t swp_pte; /* * Store the swap location in the pte. * See handle_pte_fault() ... */ |
eb94a8784 mm: fix lazyfree ... |
1501 1502 |
if (unlikely(PageSwapBacked(page) != PageSwapCache(page))) { WARN_ON_ONCE(1); |
83612a948 mm: remove SWAP_[... |
1503 |
ret = false; |
369ea8242 mm/rmap: update t... |
1504 |
/* We have to invalidate as we cleared the pte */ |
0f10851ea mm/mmu_notifier: ... |
1505 1506 |
mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); |
eb94a8784 mm: fix lazyfree ... |
1507 1508 1509 |
page_vma_mapped_walk_done(&pvmw); break; } |
c7ab0d2fd mm: convert try_t... |
1510 |
|
802a3a92a mm: reclaim MADV_... |
1511 1512 1513 |
/* MADV_FREE page check */ if (!PageSwapBacked(page)) { if (!PageDirty(page)) { |
0f10851ea mm/mmu_notifier: ... |
1514 1515 1516 |
/* Invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); |
802a3a92a mm: reclaim MADV_... |
1517 1518 1519 1520 1521 1522 1523 1524 |
dec_mm_counter(mm, MM_ANONPAGES); goto discard; } /* * If the page was redirtied, it cannot be * discarded. Remap the page to page table. */ |
785373b4c Revert "rmap: do ... |
1525 |
set_pte_at(mm, address, pvmw.pte, pteval); |
18863d3a3 mm: remove SWAP_D... |
1526 |
SetPageSwapBacked(page); |
e4b822227 mm: make rmap_one... |
1527 |
ret = false; |
802a3a92a mm: reclaim MADV_... |
1528 1529 |
page_vma_mapped_walk_done(&pvmw); break; |
c7ab0d2fd mm: convert try_t... |
1530 |
} |
854e9ed09 mm: support madvi... |
1531 |
|
c7ab0d2fd mm: convert try_t... |
1532 |
if (swap_duplicate(entry) < 0) { |
785373b4c Revert "rmap: do ... |
1533 |
set_pte_at(mm, address, pvmw.pte, pteval); |
e4b822227 mm: make rmap_one... |
1534 |
ret = false; |
c7ab0d2fd mm: convert try_t... |
1535 1536 1537 |
page_vma_mapped_walk_done(&pvmw); break; } |
ca827d55e mm, swap: Add inf... |
1538 1539 1540 1541 1542 1543 |
if (arch_unmap_one(mm, vma, address, pteval) < 0) { set_pte_at(mm, address, pvmw.pte, pteval); ret = false; page_vma_mapped_walk_done(&pvmw); break; } |
c7ab0d2fd mm: convert try_t... |
1544 1545 1546 1547 1548 1549 |
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); } |
854e9ed09 mm: support madvi... |
1550 |
dec_mm_counter(mm, MM_ANONPAGES); |
c7ab0d2fd mm: convert try_t... |
1551 1552 1553 1554 |
inc_mm_counter(mm, MM_SWAPENTS); swp_pte = swp_entry_to_pte(entry); if (pte_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); |
785373b4c Revert "rmap: do ... |
1555 |
set_pte_at(mm, address, pvmw.pte, swp_pte); |
0f10851ea mm/mmu_notifier: ... |
1556 1557 1558 1559 1560 |
/* Invalidate as we cleared the pte */ mmu_notifier_invalidate_range(mm, address, address + PAGE_SIZE); } else { /* |
69697e6a6 mm/huge_memory: r... |
1561 1562 1563 |
* This is a locked file-backed page, thus it cannot * be removed from the page cache and replaced by a new * page before mmu_notifier_invalidate_range_end, so no |
0f10851ea mm/mmu_notifier: ... |
1564 1565 1566 1567 |
* concurrent thread might update its page table to * point at new page while a device still is using this * page. * |
ad56b738c docs/vm: rename d... |
1568 |
* See Documentation/vm/mmu_notifier.rst |
0f10851ea mm/mmu_notifier: ... |
1569 |
*/ |
c7ab0d2fd mm: convert try_t... |
1570 |
dec_mm_counter(mm, mm_counter_file(page)); |
0f10851ea mm/mmu_notifier: ... |
1571 |
} |
854e9ed09 mm: support madvi... |
1572 |
discard: |
0f10851ea mm/mmu_notifier: ... |
1573 1574 1575 1576 1577 |
/* * No need to call mmu_notifier_invalidate_range() it has be * done above for all cases requiring it to happen under page * table lock before mmu_notifier_invalidate_range_end() * |
ad56b738c docs/vm: rename d... |
1578 |
* See Documentation/vm/mmu_notifier.rst |
0f10851ea mm/mmu_notifier: ... |
1579 |
*/ |
c7ab0d2fd mm: convert try_t... |
1580 1581 |
page_remove_rmap(subpage, PageHuge(page)); put_page(page); |
c7ab0d2fd mm: convert try_t... |
1582 |
} |
369ea8242 mm/rmap: update t... |
1583 1584 |
mmu_notifier_invalidate_range_end(vma->vm_mm, start, end); |
caed0f486 mm: simplify try_... |
1585 |
return ret; |
1da177e4c Linux-2.6.12-rc2 |
1586 |
} |
71e3aac07 thp: transparent ... |
1587 |
bool is_vma_temporary_stack(struct vm_area_struct *vma) |
a8bef8ff6 mm: migration: av... |
1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 |
{ 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; } |
526295064 mm/rmap: use rmap... |
1600 1601 1602 1603 |
static bool invalid_migration_vma(struct vm_area_struct *vma, void *arg) { return is_vma_temporary_stack(vma); } |
2a52bcbcc rmap: extend try_... |
1604 |
static int page_mapcount_is_zero(struct page *page) |
526295064 mm/rmap: use rmap... |
1605 |
{ |
c7ab0d2fd mm: convert try_t... |
1606 |
return !total_mapcount(page); |
2a52bcbcc rmap: extend try_... |
1607 |
} |
526295064 mm/rmap: use rmap... |
1608 |
|
1da177e4c Linux-2.6.12-rc2 |
1609 1610 1611 |
/** * try_to_unmap - try to remove all page table mappings to a page * @page: the page to get unmapped |
14fa31b89 HWPOISON: Use bit... |
1612 |
* @flags: action and flags |
1da177e4c Linux-2.6.12-rc2 |
1613 1614 1615 |
* * Tries to remove all the page table entries which are mapping this * page, used in the pageout path. Caller must hold the page lock. |
1da177e4c Linux-2.6.12-rc2 |
1616 |
* |
666e5a406 mm: make ttu's re... |
1617 |
* If unmap is successful, return true. Otherwise, false. |
1da177e4c Linux-2.6.12-rc2 |
1618 |
*/ |
666e5a406 mm: make ttu's re... |
1619 |
bool try_to_unmap(struct page *page, enum ttu_flags flags) |
1da177e4c Linux-2.6.12-rc2 |
1620 |
{ |
526295064 mm/rmap: use rmap... |
1621 1622 |
struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, |
802a3a92a mm: reclaim MADV_... |
1623 |
.arg = (void *)flags, |
2a52bcbcc rmap: extend try_... |
1624 |
.done = page_mapcount_is_zero, |
526295064 mm/rmap: use rmap... |
1625 1626 |
.anon_lock = page_lock_anon_vma_read, }; |
1da177e4c Linux-2.6.12-rc2 |
1627 |
|
526295064 mm/rmap: use rmap... |
1628 1629 1630 1631 1632 1633 1634 1635 |
/* * 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. */ |
b5ff8161e mm: thp: introduc... |
1636 1637 |
if ((flags & (TTU_MIGRATION|TTU_SPLIT_FREEZE)) && !PageKsm(page) && PageAnon(page)) |
526295064 mm/rmap: use rmap... |
1638 |
rwc.invalid_vma = invalid_migration_vma; |
2a52bcbcc rmap: extend try_... |
1639 |
if (flags & TTU_RMAP_LOCKED) |
33fc80e25 mm: remove SWAP_A... |
1640 |
rmap_walk_locked(page, &rwc); |
2a52bcbcc rmap: extend try_... |
1641 |
else |
33fc80e25 mm: remove SWAP_A... |
1642 |
rmap_walk(page, &rwc); |
526295064 mm/rmap: use rmap... |
1643 |
|
666e5a406 mm: make ttu's re... |
1644 |
return !page_mapcount(page) ? true : false; |
1da177e4c Linux-2.6.12-rc2 |
1645 |
} |
81b4082dc [PATCH] mm: rmap.... |
1646 |
|
2a52bcbcc rmap: extend try_... |
1647 1648 1649 1650 |
static int page_not_mapped(struct page *page) { return !page_mapped(page); }; |
b291f0003 mlock: mlocked pa... |
1651 1652 1653 1654 1655 1656 1657 |
/** * 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. |
b291f0003 mlock: mlocked pa... |
1658 |
*/ |
854e9ed09 mm: support madvi... |
1659 |
|
192d72325 mm: make try_to_m... |
1660 1661 |
void try_to_munlock(struct page *page) { |
e8351ac9b mm/rmap: use rmap... |
1662 1663 |
struct rmap_walk_control rwc = { .rmap_one = try_to_unmap_one, |
802a3a92a mm: reclaim MADV_... |
1664 |
.arg = (void *)TTU_MUNLOCK, |
e8351ac9b mm/rmap: use rmap... |
1665 |
.done = page_not_mapped, |
e8351ac9b mm/rmap: use rmap... |
1666 1667 1668 |
.anon_lock = page_lock_anon_vma_read, }; |
309381fea mm: dump page whe... |
1669 |
VM_BUG_ON_PAGE(!PageLocked(page) || PageLRU(page), page); |
192d72325 mm: make try_to_m... |
1670 |
VM_BUG_ON_PAGE(PageCompound(page) && PageDoubleMap(page), page); |
b291f0003 mlock: mlocked pa... |
1671 |
|
192d72325 mm: make try_to_m... |
1672 |
rmap_walk(page, &rwc); |
b291f0003 mlock: mlocked pa... |
1673 |
} |
e9995ef97 ksm: rmap_walk to... |
1674 |
|
01d8b20de mm: simplify anon... |
1675 |
void __put_anon_vma(struct anon_vma *anon_vma) |
76545066c mm: extend KSM re... |
1676 |
{ |
01d8b20de mm: simplify anon... |
1677 |
struct anon_vma *root = anon_vma->root; |
76545066c mm: extend KSM re... |
1678 |
|
624483f3e mm: rmap: fix use... |
1679 |
anon_vma_free(anon_vma); |
01d8b20de mm: simplify anon... |
1680 1681 |
if (root != anon_vma && atomic_dec_and_test(&root->refcount)) anon_vma_free(root); |
76545066c mm: extend KSM re... |
1682 |
} |
76545066c mm: extend KSM re... |
1683 |
|
0dd1c7bbc mm/rmap: extend r... |
1684 1685 |
static struct anon_vma *rmap_walk_anon_lock(struct page *page, struct rmap_walk_control *rwc) |
faecd8dd8 mm/rmap: factor l... |
1686 1687 |
{ struct anon_vma *anon_vma; |
0dd1c7bbc mm/rmap: extend r... |
1688 1689 |
if (rwc->anon_lock) return rwc->anon_lock(page); |
faecd8dd8 mm/rmap: factor l... |
1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 |
/* * Note: remove_migration_ptes() cannot use page_lock_anon_vma_read() * because that depends on page_mapped(); but not all its usages * are holding mmap_sem. Users without mmap_sem are required to * take a reference count to prevent the anon_vma disappearing */ anon_vma = page_anon_vma(page); if (!anon_vma) return NULL; anon_vma_lock_read(anon_vma); return anon_vma; } |
e9995ef97 ksm: rmap_walk to... |
1703 |
/* |
e8351ac9b mm/rmap: use rmap... |
1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 |
* rmap_walk_anon - do something to anonymous page using the object-based * rmap method * @page: the page to be handled * @rwc: control variable according to each walk type * * Find all the mappings of a page using the mapping pointer and the vma chains * contained in the anon_vma struct it points to. * * 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. |
e9995ef97 ksm: rmap_walk to... |
1716 |
*/ |
1df631ae1 mm: make rmap_wal... |
1717 |
static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc, |
b97731992 rmap: introduce r... |
1718 |
bool locked) |
e9995ef97 ksm: rmap_walk to... |
1719 1720 |
{ struct anon_vma *anon_vma; |
a8fa41ad2 mm, rmap: check a... |
1721 |
pgoff_t pgoff_start, pgoff_end; |
5beb49305 mm: change anon_v... |
1722 |
struct anon_vma_chain *avc; |
e9995ef97 ksm: rmap_walk to... |
1723 |
|
b97731992 rmap: introduce r... |
1724 1725 1726 1727 1728 1729 1730 |
if (locked) { anon_vma = page_anon_vma(page); /* anon_vma disappear under us? */ VM_BUG_ON_PAGE(!anon_vma, page); } else { anon_vma = rmap_walk_anon_lock(page, rwc); } |
e9995ef97 ksm: rmap_walk to... |
1731 |
if (!anon_vma) |
1df631ae1 mm: make rmap_wal... |
1732 |
return; |
faecd8dd8 mm/rmap: factor l... |
1733 |
|
a8fa41ad2 mm, rmap: check a... |
1734 1735 1736 1737 |
pgoff_start = page_to_pgoff(page); pgoff_end = pgoff_start + hpage_nr_pages(page) - 1; anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff_start, pgoff_end) { |
5beb49305 mm: change anon_v... |
1738 |
struct vm_area_struct *vma = avc->vma; |
e9995ef97 ksm: rmap_walk to... |
1739 |
unsigned long address = vma_address(page, vma); |
0dd1c7bbc mm/rmap: extend r... |
1740 |
|
ad12695f1 ksm: add cond_res... |
1741 |
cond_resched(); |
0dd1c7bbc mm/rmap: extend r... |
1742 1743 |
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) continue; |
e4b822227 mm: make rmap_one... |
1744 |
if (!rwc->rmap_one(page, vma, address, rwc->arg)) |
e9995ef97 ksm: rmap_walk to... |
1745 |
break; |
0dd1c7bbc mm/rmap: extend r... |
1746 1747 |
if (rwc->done && rwc->done(page)) break; |
e9995ef97 ksm: rmap_walk to... |
1748 |
} |
b97731992 rmap: introduce r... |
1749 1750 1751 |
if (!locked) anon_vma_unlock_read(anon_vma); |
e9995ef97 ksm: rmap_walk to... |
1752 |
} |
e8351ac9b mm/rmap: use rmap... |
1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 |
/* * rmap_walk_file - do something to file page using the object-based rmap method * @page: the page to be handled * @rwc: control variable according to each walk type * * Find all the mappings of a page using the mapping pointer and the vma chains * contained in the address_space struct it points to. * * 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. */ |
1df631ae1 mm: make rmap_wal... |
1766 |
static void rmap_walk_file(struct page *page, struct rmap_walk_control *rwc, |
b97731992 rmap: introduce r... |
1767 |
bool locked) |
e9995ef97 ksm: rmap_walk to... |
1768 |
{ |
b97731992 rmap: introduce r... |
1769 |
struct address_space *mapping = page_mapping(page); |
a8fa41ad2 mm, rmap: check a... |
1770 |
pgoff_t pgoff_start, pgoff_end; |
e9995ef97 ksm: rmap_walk to... |
1771 |
struct vm_area_struct *vma; |
e9995ef97 ksm: rmap_walk to... |
1772 |
|
9f32624be mm/rmap: use rmap... |
1773 1774 1775 1776 |
/* * 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, |
c8c06efa8 mm: convert i_mma... |
1777 |
* so we can safely take mapping->i_mmap_rwsem. |
9f32624be mm/rmap: use rmap... |
1778 |
*/ |
81d1b09c6 mm: convert a few... |
1779 |
VM_BUG_ON_PAGE(!PageLocked(page), page); |
9f32624be mm/rmap: use rmap... |
1780 |
|
e9995ef97 ksm: rmap_walk to... |
1781 |
if (!mapping) |
1df631ae1 mm: make rmap_wal... |
1782 |
return; |
3dec0ba0b mm/rmap: share th... |
1783 |
|
a8fa41ad2 mm, rmap: check a... |
1784 1785 |
pgoff_start = page_to_pgoff(page); pgoff_end = pgoff_start + hpage_nr_pages(page) - 1; |
b97731992 rmap: introduce r... |
1786 1787 |
if (!locked) i_mmap_lock_read(mapping); |
a8fa41ad2 mm, rmap: check a... |
1788 1789 |
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff_start, pgoff_end) { |
e9995ef97 ksm: rmap_walk to... |
1790 |
unsigned long address = vma_address(page, vma); |
0dd1c7bbc mm/rmap: extend r... |
1791 |
|
ad12695f1 ksm: add cond_res... |
1792 |
cond_resched(); |
0dd1c7bbc mm/rmap: extend r... |
1793 1794 |
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg)) continue; |
e4b822227 mm: make rmap_one... |
1795 |
if (!rwc->rmap_one(page, vma, address, rwc->arg)) |
0dd1c7bbc mm/rmap: extend r... |
1796 1797 1798 |
goto done; if (rwc->done && rwc->done(page)) goto done; |
e9995ef97 ksm: rmap_walk to... |
1799 |
} |
0dd1c7bbc mm/rmap: extend r... |
1800 |
|
0dd1c7bbc mm/rmap: extend r... |
1801 |
done: |
b97731992 rmap: introduce r... |
1802 1803 |
if (!locked) i_mmap_unlock_read(mapping); |
e9995ef97 ksm: rmap_walk to... |
1804 |
} |
1df631ae1 mm: make rmap_wal... |
1805 |
void rmap_walk(struct page *page, struct rmap_walk_control *rwc) |
e9995ef97 ksm: rmap_walk to... |
1806 |
{ |
e9995ef97 ksm: rmap_walk to... |
1807 |
if (unlikely(PageKsm(page))) |
1df631ae1 mm: make rmap_wal... |
1808 |
rmap_walk_ksm(page, rwc); |
e9995ef97 ksm: rmap_walk to... |
1809 |
else if (PageAnon(page)) |
1df631ae1 mm: make rmap_wal... |
1810 |
rmap_walk_anon(page, rwc, false); |
b97731992 rmap: introduce r... |
1811 |
else |
1df631ae1 mm: make rmap_wal... |
1812 |
rmap_walk_file(page, rwc, false); |
b97731992 rmap: introduce r... |
1813 1814 1815 |
} /* Like rmap_walk, but caller holds relevant rmap lock */ |
1df631ae1 mm: make rmap_wal... |
1816 |
void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc) |
b97731992 rmap: introduce r... |
1817 1818 1819 1820 |
{ /* no ksm support for now */ VM_BUG_ON_PAGE(PageKsm(page), page); if (PageAnon(page)) |
1df631ae1 mm: make rmap_wal... |
1821 |
rmap_walk_anon(page, rwc, true); |
e9995ef97 ksm: rmap_walk to... |
1822 |
else |
1df631ae1 mm: make rmap_wal... |
1823 |
rmap_walk_file(page, rwc, true); |
e9995ef97 ksm: rmap_walk to... |
1824 |
} |
0fe6e20b9 hugetlb, rmap: ad... |
1825 |
|
e3390f67a hwpoison: rename ... |
1826 |
#ifdef CONFIG_HUGETLB_PAGE |
0fe6e20b9 hugetlb, rmap: ad... |
1827 1828 1829 1830 1831 1832 1833 1834 1835 |
/* * 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... |
1836 |
|
0fe6e20b9 hugetlb, rmap: ad... |
1837 |
BUG_ON(!anon_vma); |
433abed6c hugetlb, rmap: al... |
1838 1839 1840 1841 1842 |
if (PageAnon(page)) return; if (!exclusive) anon_vma = anon_vma->root; |
0fe6e20b9 hugetlb, rmap: ad... |
1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 |
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... |
1853 1854 |
BUG_ON(!PageLocked(page)); |
0fe6e20b9 hugetlb, rmap: ad... |
1855 |
BUG_ON(!anon_vma); |
5dbe0af47 mm: fix kernel BU... |
1856 |
/* address might be in next vma when migration races vma_adjust */ |
53f9263ba mm: rework mapcou... |
1857 |
first = atomic_inc_and_test(compound_mapcount_ptr(page)); |
0fe6e20b9 hugetlb, rmap: ad... |
1858 1859 1860 1861 1862 1863 1864 1865 |
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); |
53f9263ba mm: rework mapcou... |
1866 |
atomic_set(compound_mapcount_ptr(page), 0); |
0fe6e20b9 hugetlb, rmap: ad... |
1867 1868 |
__hugepage_set_anon_rmap(page, vma, address, 1); } |
e3390f67a hwpoison: rename ... |
1869 |
#endif /* CONFIG_HUGETLB_PAGE */ |