X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=mm%2Ffilemap.c;h=90effcdf948d6c463afa817e277e7eae94b657a6;hb=06b8ab55289345ab191bf4bf0e4acc6d4bdf293d;hp=900edfaf6df5735a1979c866cd288c46c81e50ca;hpb=cc568ead3ce8e0284e7e2cc77bd1dafb03ba4ca1;p=firefly-linux-kernel-4.4.55.git diff --git a/mm/filemap.c b/mm/filemap.c index 900edfaf6df5..90effcdf948d 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -31,6 +31,7 @@ #include #include #include /* for BUG_ON(!in_atomic()) only */ +#include #include #include #include @@ -233,7 +234,6 @@ void delete_from_page_cache(struct page *page) spin_lock_irq(&mapping->tree_lock); __delete_from_page_cache(page, NULL); spin_unlock_irq(&mapping->tree_lock); - mem_cgroup_uncharge_cache_page(page); if (freepage) freepage(page); @@ -241,18 +241,6 @@ void delete_from_page_cache(struct page *page) } EXPORT_SYMBOL(delete_from_page_cache); -static int sleep_on_page(void *word) -{ - io_schedule(); - return 0; -} - -static int sleep_on_page_killable(void *word) -{ - sleep_on_page(word); - return fatal_signal_pending(current) ? -EINTR : 0; -} - static int filemap_check_errors(struct address_space *mapping) { int ret = 0; @@ -501,8 +489,7 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) if (PageSwapBacked(new)) __inc_zone_page_state(new, NR_SHMEM); spin_unlock_irq(&mapping->tree_lock); - /* mem_cgroup codes must not be called under tree_lock */ - mem_cgroup_replace_page_cache(old, new); + mem_cgroup_migrate(old, new, true); radix_tree_preload_end(); if (freepage) freepage(old); @@ -560,19 +547,24 @@ static int __add_to_page_cache_locked(struct page *page, pgoff_t offset, gfp_t gfp_mask, void **shadowp) { + int huge = PageHuge(page); + struct mem_cgroup *memcg; int error; VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageSwapBacked(page), page); - error = mem_cgroup_charge_file(page, current->mm, - gfp_mask & GFP_RECLAIM_MASK); - if (error) - return error; + if (!huge) { + error = mem_cgroup_try_charge(page, current->mm, + gfp_mask, &memcg); + if (error) + return error; + } error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM); if (error) { - mem_cgroup_uncharge_cache_page(page); + if (!huge) + mem_cgroup_cancel_charge(page, memcg); return error; } @@ -587,13 +579,16 @@ static int __add_to_page_cache_locked(struct page *page, goto err_insert; __inc_zone_page_state(page, NR_FILE_PAGES); spin_unlock_irq(&mapping->tree_lock); + if (!huge) + mem_cgroup_commit_charge(page, memcg, false); trace_mm_filemap_add_to_page_cache(page); return 0; err_insert: page->mapping = NULL; /* Leave page->index set: truncation relies upon it */ spin_unlock_irq(&mapping->tree_lock); - mem_cgroup_uncharge_cache_page(page); + if (!huge) + mem_cgroup_cancel_charge(page, memcg); page_cache_release(page); return error; } @@ -692,7 +687,7 @@ void wait_on_page_bit(struct page *page, int bit_nr) DEFINE_WAIT_BIT(wait, &page->flags, bit_nr); if (test_bit(bit_nr, &page->flags)) - __wait_on_bit(page_waitqueue(page), &wait, sleep_on_page, + __wait_on_bit(page_waitqueue(page), &wait, bit_wait_io, TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL(wait_on_page_bit); @@ -705,7 +700,7 @@ int wait_on_page_bit_killable(struct page *page, int bit_nr) return 0; return __wait_on_bit(page_waitqueue(page), &wait, - sleep_on_page_killable, TASK_KILLABLE); + bit_wait_io, TASK_KILLABLE); } /** @@ -806,7 +801,7 @@ void __lock_page(struct page *page) { DEFINE_WAIT_BIT(wait, &page->flags, PG_locked); - __wait_on_bit_lock(page_waitqueue(page), &wait, sleep_on_page, + __wait_on_bit_lock(page_waitqueue(page), &wait, bit_wait_io, TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL(__lock_page); @@ -816,10 +811,21 @@ int __lock_page_killable(struct page *page) DEFINE_WAIT_BIT(wait, &page->flags, PG_locked); return __wait_on_bit_lock(page_waitqueue(page), &wait, - sleep_on_page_killable, TASK_KILLABLE); + bit_wait_io, TASK_KILLABLE); } EXPORT_SYMBOL_GPL(__lock_page_killable); +/* + * Return values: + * 1 - page is locked; mmap_sem is still held. + * 0 - page is not locked. + * mmap_sem has been released (up_read()), unless flags had both + * FAULT_FLAG_ALLOW_RETRY and FAULT_FLAG_RETRY_NOWAIT set, in + * which case mmap_sem is still held. + * + * If neither ALLOW_RETRY nor KILLABLE are set, will always return 1 + * with the page locked and the mmap_sem unperturbed. + */ int __lock_page_or_retry(struct page *page, struct mm_struct *mm, unsigned int flags) { @@ -1103,9 +1109,9 @@ no_page: if (WARN_ON_ONCE(!(fgp_flags & FGP_LOCK))) fgp_flags |= FGP_LOCK; - /* Init accessed so avoit atomic mark_page_accessed later */ + /* Init accessed so avoid atomic mark_page_accessed later */ if (fgp_flags & FGP_ACCESSED) - init_page_accessed(page); + __SetPageReferenced(page); err = add_to_page_cache_lru(page, mapping, offset, radix_gfp_mask); if (unlikely(err)) { @@ -1839,6 +1845,18 @@ static void do_async_mmap_readahead(struct vm_area_struct *vma, * The goto's are kind of ugly, but this streamlines the normal case of having * it in the page cache, and handles the special cases reasonably without * having a lot of duplicated code. + * + * vma->vm_mm->mmap_sem must be held on entry. + * + * If our return value has VM_FAULT_RETRY set, it's because + * lock_page_or_retry() returned 0. + * The mmap_sem has usually been released in this case. + * See __lock_page_or_retry() for the exception. + * + * If our return value does not have VM_FAULT_RETRY set, the mmap_sem + * has not been released. + * + * We never return with VM_FAULT_RETRY and a bit from VM_FAULT_ERROR set. */ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { @@ -2584,7 +2602,7 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from) * that this differs from normal direct-io semantics, which * will return -EFOO even if some bytes were written. */ - if (unlikely(status < 0) && !written) { + if (unlikely(status < 0)) { err = status; goto out; }