cregit-Linux how code gets into the kernel

Release 4.8 mm/filemap.c

Directory: mm
/*
 *      linux/mm/filemap.c
 *
 * Copyright (C) 1994-1999  Linus Torvalds
 */

/*
 * This file handles the generic file mmap semantics used by
 * most "normal" filesystems (but you don't /have/ to use this:
 * the NFS filesystem used to do this differently, for example)
 */
#include <linux/export.h>
#include <linux/compiler.h>
#include <linux/dax.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/capability.h>
#include <linux/kernel_stat.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include <linux/file.h>
#include <linux/uio.h>
#include <linux/hash.h>
#include <linux/writeback.h>
#include <linux/backing-dev.h>
#include <linux/pagevec.h>
#include <linux/blkdev.h>
#include <linux/security.h>
#include <linux/cpuset.h>
#include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
#include <linux/hugetlb.h>
#include <linux/memcontrol.h>
#include <linux/cleancache.h>
#include <linux/rmap.h>
#include "internal.h"


#define CREATE_TRACE_POINTS
#include <trace/events/filemap.h>

/*
 * FIXME: remove all knowledge of the buffer layer from the core VM
 */
#include <linux/buffer_head.h> /* for try_to_free_buffers */

#include <asm/mman.h>

/*
 * Shared mappings implemented 30.11.1994. It's not fully working yet,
 * though.
 *
 * Shared mappings now work. 15.8.1995  Bruno.
 *
 * finished 'unifying' the page and buffer cache and SMP-threaded the
 * page-cache, 21.05.1999, Ingo Molnar <mingo@redhat.com>
 *
 * SMP-threaded pagemap-LRU 1999, Andrea Arcangeli <andrea@suse.de>
 */

/*
 * Lock ordering:
 *
 *  ->i_mmap_rwsem              (truncate_pagecache)
 *    ->private_lock            (__free_pte->__set_page_dirty_buffers)
 *      ->swap_lock             (exclusive_swap_page, others)
 *        ->mapping->tree_lock
 *
 *  ->i_mutex
 *    ->i_mmap_rwsem            (truncate->unmap_mapping_range)
 *
 *  ->mmap_sem
 *    ->i_mmap_rwsem
 *      ->page_table_lock or pte_lock   (various, mainly in memory.c)
 *        ->mapping->tree_lock  (arch-dependent flush_dcache_mmap_lock)
 *
 *  ->mmap_sem
 *    ->lock_page               (access_process_vm)
 *
 *  ->i_mutex                   (generic_perform_write)
 *    ->mmap_sem                (fault_in_pages_readable->do_page_fault)
 *
 *  bdi->wb.list_lock
 *    sb_lock                   (fs/fs-writeback.c)
 *    ->mapping->tree_lock      (__sync_single_inode)
 *
 *  ->i_mmap_rwsem
 *    ->anon_vma.lock           (vma_adjust)
 *
 *  ->anon_vma.lock
 *    ->page_table_lock or pte_lock     (anon_vma_prepare and various)
 *
 *  ->page_table_lock or pte_lock
 *    ->swap_lock               (try_to_unmap_one)
 *    ->private_lock            (try_to_unmap_one)
 *    ->tree_lock               (try_to_unmap_one)
 *    ->zone_lru_lock(zone)     (follow_page->mark_page_accessed)
 *    ->zone_lru_lock(zone)     (check_pte_range->isolate_lru_page)
 *    ->private_lock            (page_remove_rmap->set_page_dirty)
 *    ->tree_lock               (page_remove_rmap->set_page_dirty)
 *    bdi.wb->list_lock         (page_remove_rmap->set_page_dirty)
 *    ->inode->i_lock           (page_remove_rmap->set_page_dirty)
 *    ->memcg->move_lock        (page_remove_rmap->lock_page_memcg)
 *    bdi.wb->list_lock         (zap_pte_range->set_page_dirty)
 *    ->inode->i_lock           (zap_pte_range->set_page_dirty)
 *    ->private_lock            (zap_pte_range->__set_page_dirty_buffers)
 *
 * ->i_mmap_rwsem
 *   ->tasklist_lock            (memory_failure, collect_procs_ao)
 */


static int page_cache_tree_insert(struct address_space *mapping, struct page *page, void **shadowp) { struct radix_tree_node *node; void **slot; int error; error = __radix_tree_create(&mapping->page_tree, page->index, 0, &node, &slot); if (error) return error; if (*slot) { void *p; p = radix_tree_deref_slot_protected(slot, &mapping->tree_lock); if (!radix_tree_exceptional_entry(p)) return -EEXIST; mapping->nrexceptional--; if (!dax_mapping(mapping)) { if (shadowp) *shadowp = p; if (node) workingset_node_shadows_dec(node); } else { /* DAX can replace empty locked entry with a hole */ WARN_ON_ONCE(p != (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY | RADIX_DAX_ENTRY_LOCK)); /* DAX accounts exceptional entries as normal pages */ if (node) workingset_node_pages_dec(node); /* Wakeup waiters for exceptional entry lock */ dax_wake_mapping_entry_waiter(mapping, page->index, false); } } radix_tree_replace_slot(slot, page); mapping->nrpages++; if (node) { workingset_node_pages_inc(node); /* * Don't track node that contains actual pages. * * Avoid acquiring the list_lru lock if already * untracked. The list_empty() test is safe as * node->private_list is protected by * mapping->tree_lock. */ if (!list_empty(&node->private_list)) list_lru_del(&workingset_shadow_nodes, &node->private_list); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner221100.00%1100.00%
Total221100.00%1100.00%


static void page_cache_tree_delete(struct address_space *mapping, struct page *page, void *shadow) { struct radix_tree_node *node; int i, nr = PageHuge(page) ? 1 : hpage_nr_pages(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(nr != 1 && shadow, page); if (shadow) { mapping->nrexceptional += nr; /* * Make sure the nrexceptional update is committed before * the nrpages update so that final truncate racing * with reclaim does not see both counters 0 at the * same time and miss a shadow entry. */ smp_wmb(); } mapping->nrpages -= nr; for (i = 0; i < nr; i++) { node = radix_tree_replace_clear_tags(&mapping->page_tree, page->index + i, shadow); if (!node) { VM_BUG_ON_PAGE(nr != 1, page); return; } workingset_node_pages_dec(node); if (shadow) workingset_node_shadows_inc(node); else if (__radix_tree_delete_node(&mapping->page_tree, node)) continue; /* * Track node that only contains shadow entries. DAX mappings * contain no shadow entries and may contain other exceptional * entries so skip those. * * Avoid acquiring the list_lru lock if already tracked. * The list_empty() test is safe as node->private_list is * protected by mapping->tree_lock. */ if (!dax_mapping(mapping) && !workingset_node_pages(node) && list_empty(&node->private_list)) { node->private_data = mapping; list_lru_add(&workingset_shadow_nodes, &node->private_list); } } }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner12256.48%233.33%
kirill a. shutemovkirill a. shutemov8539.35%116.67%
jan karajan kara62.78%116.67%
ross zwislerross zwisler20.93%116.67%
matthew wilcoxmatthew wilcox10.46%116.67%
Total216100.00%6100.00%

/* * Delete a page from the page cache and free it. Caller has to make * sure the page is locked and that nobody else uses it - or that usage * is safe. The caller must hold the mapping's tree_lock. */
void __delete_from_page_cache(struct page *page, void *shadow) { struct address_space *mapping = page->mapping; int nr = hpage_nr_pages(page); trace_mm_filemap_delete_from_page_cache(page); /* * if we're uptodate, flush out into the cleancache, otherwise * invalidate any existing cleancache entries. We can't leave * stale data around in the cleancache once our page is gone */ if (PageUptodate(page) && PageMappedToDisk(page)) cleancache_put_page(page); else cleancache_invalidate_page(mapping, page); VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(page_mapped(page), page); if (!IS_ENABLED(CONFIG_DEBUG_VM) && unlikely(page_mapped(page))) { int mapcount; pr_alert("BUG: Bad page cache in process %s pfn:%05lx\n", current->comm, page_to_pfn(page)); dump_page(page, "still mapped when deleted"); dump_stack(); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); mapcount = page_mapcount(page); if (mapping_exiting(mapping) && page_count(page) >= mapcount + 2) { /* * All vmas have already been torn down, so it's * a good bet that actually the page is unmapped, * and we'd prefer not to leak it: if we're wrong, * some other bad page check should catch it later. */ page_mapcount_reset(page); page_ref_sub(page, mapcount); } } page_cache_tree_delete(mapping, page, shadow); page->mapping = NULL; /* Leave page->index set: truncation lookup relies upon it */ /* hugetlb pages do not participate in page cache accounting. */ if (!PageHuge(page)) __mod_node_page_state(page_pgdat(page), NR_FILE_PAGES, -nr); if (PageSwapBacked(page)) { __mod_node_page_state(page_pgdat(page), NR_SHMEM, -nr); if (PageTransHuge(page)) __dec_node_page_state(page, NR_SHMEM_THPS); } else { VM_BUG_ON_PAGE(PageTransHuge(page) && !PageHuge(page), page); } /* * At this point page must be either written or cleaned by truncate. * Dirty page here signals a bug and loss of unwritten data. * * This fixes dirty accounting after removing the page entirely but * leaves PageDirty set: it has no effect for truncated page and * anyway will be cleared before returning page into buddy allocator. */ if (WARN_ON_ONCE(PageDirty(page))) account_page_cleaned(page, mapping, inode_to_wb(mapping->host)); }

Contributors

PersonTokensPropCommitsCommitProp
hugh dickinshugh dickins9833.79%29.09%
kirill a. shutemovkirill a. shutemov6221.38%29.09%
pre-gitpre-git279.31%313.64%
dan magenheimerdan magenheimer268.97%29.09%
linus torvaldslinus torvalds155.17%14.55%
kosaki motohirokosaki motohiro134.48%14.55%
michal hockomichal hocko93.10%14.55%
johannes weinerjohannes weiner72.41%14.55%
tejun heotejun heo62.07%14.55%
mel gormanmel gorman51.72%14.55%
robert jarzmikrobert jarzmik51.72%14.55%
andrew mortonandrew morton51.72%14.55%
konstantin khlebnikovkonstantin khlebnikov41.38%14.55%
joonsoo kimjoonsoo kim31.03%14.55%
christoph lameterchristoph lameter31.03%14.55%
minchan kimminchan kim10.34%14.55%
greg thelengreg thelen10.34%14.55%
Total290100.00%22100.00%

/** * delete_from_page_cache - delete page from page cache * @page: the page which the kernel is trying to remove from page cache * * This must be called only on pages that have been verified to be in the page * cache and locked. It will never put the page into the free list, the caller * has a reference on the page. */
void delete_from_page_cache(struct page *page) { struct address_space *mapping = page_mapping(page); unsigned long flags; void (*freepage)(struct page *); BUG_ON(!PageLocked(page)); freepage = mapping->a_ops->freepage; spin_lock_irqsave(&mapping->tree_lock, flags); __delete_from_page_cache(page, NULL); spin_unlock_irqrestore(&mapping->tree_lock, flags); if (freepage) freepage(page); if (PageTransHuge(page) && !PageHuge(page)) { page_ref_sub(page, HPAGE_PMD_NR); VM_BUG_ON_PAGE(page_count(page) <= 0, page); } else { put_page(page); } }

Contributors

PersonTokensPropCommitsCommitProp
kirill a. shutemovkirill a. shutemov4131.54%215.38%
linus torvaldslinus torvalds2821.54%17.69%
pre-gitpre-git2720.77%215.38%
andrew mortonandrew morton129.23%215.38%
greg thelengreg thelen129.23%17.69%
minchan kimminchan kim75.38%323.08%
johannes weinerjohannes weiner21.54%17.69%
matt mackallmatt mackall10.77%17.69%
Total130100.00%13100.00%

EXPORT_SYMBOL(delete_from_page_cache);
int filemap_check_errors(struct address_space *mapping) { int ret = 0; /* Check for outstanding write errors */ if (test_bit(AS_ENOSPC, &mapping->flags) && test_and_clear_bit(AS_ENOSPC, &mapping->flags)) ret = -ENOSPC; if (test_bit(AS_EIO, &mapping->flags) && test_and_clear_bit(AS_EIO, &mapping->flags)) ret = -EIO; return ret; }

Contributors

PersonTokensPropCommitsCommitProp
dmitriy monakhovdmitriy monakhov5372.60%150.00%
jens axboejens axboe2027.40%150.00%
Total73100.00%2100.00%

EXPORT_SYMBOL(filemap_check_errors); /** * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range * @mapping: address space structure to write * @start: offset in bytes where the range starts * @end: offset in bytes where the range ends (inclusive) * @sync_mode: enable synchronous operation * * Start writeback against all of a mapping's dirty pages that lie * within the byte offsets <start, end> inclusive. * * If sync_mode is WB_SYNC_ALL then this is a "data integrity" operation, as * opposed to a regular memory cleansing writeback. The difference between * these two operations is that if a dirty page/buffer is encountered, it must * be waited upon, and not just skipped over. */
int __filemap_fdatawrite_range(struct address_space *mapping, loff_t start, loff_t end, int sync_mode) { int ret; struct writeback_control wbc = { .sync_mode = sync_mode, .nr_to_write = LONG_MAX, .range_start = start, .range_end = end, }; if (!mapping_cap_writeback_dirty(mapping)) return 0; wbc_attach_fdatawrite_inode(&wbc, mapping->host); ret = do_writepages(mapping, &wbc); wbc_detach_inode(&wbc); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton4045.45%847.06%
tejun heotejun heo1618.18%15.88%
suparna bhattacharyasuparna bhattacharya1517.05%15.88%
pre-gitpre-git910.23%317.65%
david howellsdavid howells44.55%15.88%
hirofumi ogawahirofumi ogawa22.27%15.88%
nick pigginnick piggin11.14%15.88%
linus torvaldslinus torvalds11.14%15.88%
Total88100.00%17100.00%


static inline int __filemap_fdatawrite(struct address_space *mapping, int sync_mode) { return __filemap_fdatawrite_range(mapping, 0, LLONG_MAX, sync_mode); }

Contributors

PersonTokensPropCommitsCommitProp
suparna bhattacharyasuparna bhattacharya2696.30%150.00%
hirofumi ogawahirofumi ogawa13.70%150.00%
Total27100.00%2100.00%


int filemap_fdatawrite(struct address_space *mapping) { return __filemap_fdatawrite(mapping, WB_SYNC_ALL); }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton18100.00%1100.00%
Total18100.00%1100.00%

EXPORT_SYMBOL(filemap_fdatawrite);
int filemap_fdatawrite_range(struct address_space *mapping, loff_t start, loff_t end) { return __filemap_fdatawrite_range(mapping, start, end, WB_SYNC_ALL); }

Contributors

PersonTokensPropCommitsCommitProp
suparna bhattacharyasuparna bhattacharya28100.00%1100.00%
Total28100.00%1100.00%

EXPORT_SYMBOL(filemap_fdatawrite_range); /** * filemap_flush - mostly a non-blocking flush * @mapping: target address_space * * This is a mostly non-blocking flush. Not suitable for data-integrity * purposes - I/O may not be started against all dirty pages. */
int filemap_flush(struct address_space *mapping) { return __filemap_fdatawrite(mapping, WB_SYNC_NONE); }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton18100.00%1100.00%
Total18100.00%1100.00%

EXPORT_SYMBOL(filemap_flush);
static int __filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte, loff_t end_byte) { pgoff_t index = start_byte >> PAGE_SHIFT; pgoff_t end = end_byte >> PAGE_SHIFT; struct pagevec pvec; int nr_pages; int ret = 0; if (end_byte < start_byte) goto out; pagevec_init(&pvec, 0); while ((index <= end) && (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_WRITEBACK, min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1)) != 0) { unsigned i; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; /* until radix tree lookup accepts end_index */ if (page->index > end) continue; wait_on_page_writeback(page); if (TestClearPageError(page)) ret = -EIO; } pagevec_release(&pvec); cond_resched(); } out: return ret; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton9553.98%533.33%
pre-gitpre-git1910.80%213.33%
christoph hellwigchristoph hellwig1810.23%16.67%
suparna bhattacharyasuparna bhattacharya169.09%16.67%
linus torvaldslinus torvalds126.82%16.67%
jun'ichi nomurajun'ichi nomura63.41%16.67%
dmitriy monakhovdmitriy monakhov52.84%16.67%
kirill a. shutemovkirill a. shutemov21.14%16.67%
mika kukkonenmika kukkonen21.14%16.67%
rik van rielrik van riel10.57%16.67%
Total176100.00%15100.00%

/** * filemap_fdatawait_range - wait for writeback to complete * @mapping: address space structure to wait for * @start_byte: offset in bytes where the range starts * @end_byte: offset in bytes where the range ends (inclusive) * * Walk the list of under-writeback pages of the given address space * in the given range and wait for all of them. Check error status of * the address space and return it. * * Since the error status of the address space is cleared by this function, * callers are responsible for checking the return value and handling and/or * reporting the error. */
int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte, loff_t end_byte) { int ret, ret2; ret = __filemap_fdatawait_range(mapping, start_byte, end_byte); ret2 = filemap_check_errors(mapping); if (!ret) ret = ret2; return ret; }

Contributors

PersonTokensPropCommitsCommitProp
jun'ichi nomurajun'ichi nomura3160.78%116.67%
andrew mortonandrew morton1325.49%350.00%
dmitriy monakhovdmitriy monakhov611.76%116.67%
pre-gitpre-git11.96%116.67%
Total51100.00%6100.00%

EXPORT_SYMBOL(filemap_fdatawait_range); /** * filemap_fdatawait_keep_errors - wait for writeback without clearing errors * @mapping: address space structure to wait for * * Walk the list of under-writeback pages of the given address space * and wait for all of them. Unlike filemap_fdatawait(), this function * does not clear error status of the address space. * * Use this function if callers don't handle errors themselves. Expected * call sites are system-wide / filesystem-wide data flushers: e.g. sync(2), * fsfreeze(8) */
void filemap_fdatawait_keep_errors(struct address_space *mapping) { loff_t i_size = i_size_read(mapping->host); if (i_size == 0) return; __filemap_fdatawait_range(mapping, 0, i_size - 1); }

Contributors

PersonTokensPropCommitsCommitProp
jun'ichi nomurajun'ichi nomura38100.00%1100.00%
Total38100.00%1100.00%

/** * filemap_fdatawait - wait for all under-writeback pages to complete * @mapping: address space structure to wait for * * Walk the list of under-writeback pages of the given address space * and wait for all of them. Check error status of the address space * and return it. * * Since the error status of the address space is cleared by this function, * callers are responsible for checking the return value and handling and/or * reporting the error. */
int filemap_fdatawait(struct address_space *mapping) { loff_t i_size = i_size_read(mapping->host); if (i_size == 0) return 0; return filemap_fdatawait_range(mapping, 0, i_size - 1); }

Contributors

PersonTokensPropCommitsCommitProp
marcelo tosattimarcelo tosatti2048.78%133.33%
andrew mortonandrew morton2048.78%133.33%
christoph hellwigchristoph hellwig12.44%133.33%
Total41100.00%3100.00%

EXPORT_SYMBOL(filemap_fdatawait);
int filemap_write_and_wait(struct address_space *mapping) { int err = 0; if ((!dax_mapping(mapping) && mapping->nrpages) || (dax_mapping(mapping) && mapping->nrexceptional)) { err = filemap_fdatawrite(mapping); /* * Even if the above returned error, the pages may be * written partially (e.g. -ENOSPC), so we wait for it. * But the -EIO is special case, it may indicate the worst * thing (e.g. bug) happened, so we avoid waiting for it. */ if (err != -EIO) { int err2 = filemap_fdatawait(mapping); if (!err) err = err2; } } else { err = filemap_check_errors(mapping); } return err; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton3842.70%125.00%
hirofumi ogawahirofumi ogawa2224.72%125.00%
ross zwislerross zwisler1921.35%125.00%
dmitriy monakhovdmitriy monakhov1011.24%125.00%
Total89100.00%4100.00%

EXPORT_SYMBOL(filemap_write_and_wait); /** * filemap_write_and_wait_range - write out & wait on a file range * @mapping: the address_space for the pages * @lstart: offset in bytes where the range starts * @lend: offset in bytes where the range ends (inclusive) * * Write out and wait upon file offsets lstart->lend, inclusive. * * Note that `lend' is inclusive (describes the last byte to be written) so * that this function can be used to write to the very end-of-file (end = -1). */
int filemap_write_and_wait_range(struct address_space *mapping, loff_t lstart, loff_t lend) { int err = 0; if ((!dax_mapping(mapping) && mapping->nrpages) || (dax_mapping(mapping) && mapping->nrexceptional)) { err = __filemap_fdatawrite_range(mapping, lstart, lend, WB_SYNC_ALL); /* See comment of filemap_write_and_wait() */ if (err != -EIO) { int err2 = filemap_fdatawait_range(mapping, lstart, lend); if (!err) err = err2; } } else { err = filemap_check_errors(mapping); } return err; }

Contributors

PersonTokensPropCommitsCommitProp
zach brownzach brown5249.52%116.67%
hirofumi ogawahirofumi ogawa2220.95%116.67%
ross zwislerross zwisler2019.05%233.33%
dmitriy monakhovdmitriy monakhov109.52%116.67%
christoph hellwigchristoph hellwig10.95%116.67%
Total105100.00%6100.00%

EXPORT_SYMBOL(filemap_write_and_wait_range); /** * replace_page_cache_page - replace a pagecache page with a new one * @old: page to be replaced * @new: page to replace with * @gfp_mask: allocation mode * * This function replaces a page in the pagecache with a new one. On * success it acquires the pagecache reference for the new page and * drops it for the old page. Both the old and new pages must be * locked. This function does not add the new page to the LRU, the * caller must do that. * * The remove + add is atomic. The only way this function can fail is * memory allocation failure. */
int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) { int error; VM_BUG_ON_PAGE(!PageLocked(old), old); VM_BUG_ON_PAGE(!PageLocked(new), new); VM_BUG_ON_PAGE(new->mapping, new); error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM); if (!error) { struct address_space *mapping = old->mapping; void (*freepage)(struct page *); unsigned long flags; pgoff_t offset = old->index; freepage = mapping->a_ops->freepage; get_page(new); new->mapping = mapping; new->index = offset; spin_lock_irqsave(&mapping->tree_lock, flags); __delete_from_page_cache(old, NULL); error = page_cache_tree_insert(mapping, new, NULL); BUG_ON(error); mapping->nrpages++; /* * hugetlb pages do not participate in page cache accounting. */ if (!PageHuge(new)) __inc_node_page_state(new, NR_FILE_PAGES); if (PageSwapBacked(new)) __inc_node_page_state(new, NR_SHMEM); spin_unlock_irqrestore(&mapping->tree_lock, flags); mem_cgroup_migrate(old, new); radix_tree_preload_end(); if (freepage) freepage(old); put_page(old); } return error; }

Contributors

PersonTokensPropCommitsCommitProp
miklos szeredimiklos szeredi18379.57%19.09%
greg thelengreg thelen125.22%19.09%
sasha levinsasha levin93.91%19.09%
michal hockomichal hocko93.91%19.09%
johannes weinerjohannes weiner62.61%327.27%
kamezawa hiroyukikamezawa hiroyuki62.61%19.09%
mel gormanmel gorman20.87%19.09%
kirill a. shutemovkirill a. shutemov20.87%19.09%
minchan kimminchan kim10.43%19.09%
Total230100.00%11100.00%

EXPORT_SYMBOL_GPL(replace_page_cache_page);
static int __add_to_page_cache_locked(struct page *page, struct address_space *mapping, 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); if (!huge) { error = mem_cgroup_try_charge(page, current->mm, gfp_mask, &memcg, false); if (error) return error; } error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM); if (error) { if (!huge) mem_cgroup_cancel_charge(page, memcg, false); return error; } get_page(page); page->mapping = mapping; page->index = offset; spin_lock_irq(&mapping->tree_lock); error = page_cache_tree_insert(mapping, page, shadowp); radix_tree_preload_end(); if (unlikely(error)) goto err_insert; /* hugetlb pages do not participate in page cache accounting. */ if (!huge) __inc_node_page_state(page, NR_FILE_PAGES); spin_unlock_irq(&mapping->tree_lock); if (!huge) mem_cgroup_commit_charge(page, memcg, false, 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); if (!huge) mem_cgroup_cancel_charge(page, memcg, false); put_page(page); return error; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner6324.05%38.82%
nick pigginnick piggin4115.65%25.88%
kirill a. shutemovkirill a. shutemov3312.60%38.82%
andrew mortonandrew morton3312.60%617.65%
balbir singhbalbir singh249.16%38.82%
daisuke nishimuradaisuke nishimura166.11%12.94%
pre-gitpre-git124.58%38.82%
hugh dickinshugh dickins83.05%25.88%
linus torvaldslinus torvalds83.05%38.82%
michal hockomichal hocko62.29%12.94%
sasha levinsasha levin62.29%12.94%
robert jarzmikrobert jarzmik51.91%12.94%
christoph lameterchristoph lameter31.15%12.94%
jan karajan kara10.38%12.94%
al viroal viro10.38%12.94%
mel gormanmel gorman10.38%12.94%
badari pulavartybadari pulavarty10.38%12.94%
Total262100.00%34100.00%

/** * add_to_page_cache_locked - add a locked page to the pagecache * @page: page to add * @mapping: the page's address_space * @offset: page index * @gfp_mask: page allocation mode * * This function is used to add a page to the pagecache. It must be locked. * This function does not add the page to the LRU. The caller must do that. */
int add_to_page_cache_locked(struct page *page, struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask) { return __add_to_page_cache_locked(page, mapping, offset, gfp_mask, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner35100.00%1100.00%
Total35100.00%1100.00%

EXPORT_SYMBOL(add_to_page_cache_locked);
int add_to_page_cache_lru(struct page *page, struct address_space *mapping, pgoff_t offset, gfp_t gfp_mask) { void *shadow = NULL; int ret; __SetPageLocked(page); ret = __add_to_page_cache_locked(page, mapping, offset, gfp_mask, &shadow); if (unlikely(ret)) __ClearPageLocked(page); else { /* * The page might have been evicted from cache only * recently, in which case it should be activated like * any other repeatedly accessed page. * The exception is pages getting rewritten; evicting other * data from the working set, only to cache data that will * get overwritten with something else, is a waste of memory. */ if (!(gfp_mask & __GFP_WRITE) && shadow && workingset_refault(shadow)) { SetPageActive(page); workingset_activation(page); } else ClearPageActive(page); lru_cache_add(page); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner5247.71%19.09%
andrew mortonandrew morton3431.19%327.27%
rik van rielrik van riel1614.68%218.18%
linus torvaldslinus torvalds32.75%218.18%
kirill a. shutemovkirill a. shutemov21.83%19.09%
al viroal viro10.92%19.09%
pre-gitpre-git10.92%19.09%
Total109100.00%11100.00%

EXPORT_SYMBOL_GPL(add_to_page_cache_lru); #ifdef CONFIG_NUMA
struct page *__page_cache_alloc(gfp_t gfp) { int n; struct page *page; if (cpuset_do_page_mem_spread()) { unsigned int cpuset_mems_cookie; do { cpuset_mems_cookie = read_mems_allowed_begin(); n = cpuset_mem_spread_node(); page = __alloc_pages_node(n, gfp, 0); } while (!page && read_mems_allowed_retry(cpuset_mems_cookie)); return page; } return alloc_pages(gfp, 0); }

Contributors

PersonTokensPropCommitsCommitProp
paul jacksonpaul jackson3141.33%116.67%
mel gormanmel gorman2128.00%233.33%
miao xiemiao xie1722.67%116.67%
nick pigginnick piggin56.67%116.67%
vlastimil babkavlastimil babka11.33%116.67%
Total75100.00%6100.00%

EXPORT_SYMBOL(__page_cache_alloc); #endif /* * In order to wait for pages to become available there must be * waitqueues associated with pages. By using a hash table of * waitqueues where the bucket discipline is to maintain all * waiters on the same queue and wake all when any of the pages * become available, and for the woken contexts to check to be * sure the appropriate page became available, this saves space * at a cost of "thundering herd" phenomena during rare hash * collisions. */
wait_queue_head_t *page_waitqueue(struct page *page) { const struct zone *zone = page_zone(page); return &zone->wait_table[hash_ptr(page, zone->wait_table_bits)]; }

Contributors

PersonTokensPropCommitsCommitProp
rik van rielrik van riel2873.68%133.33%
rusty russellrusty russell821.05%133.33%
andrew mortonandrew morton25.26%133.33%
Total38100.00%3100.00%

EXPORT_SYMBOL(page_waitqueue);
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, bit_wait_io, TASK_UNINTERRUPTIBLE); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds2140.38%111.11%
william lee irwin iiiwilliam lee irwin iii1630.77%222.22%
andrew mortonandrew morton1121.15%444.44%
rik van rielrik van riel35.77%111.11%
neil brownneil brown11.92%111.11%
Total52100.00%9100.00%

EXPORT_SYMBOL(wait_on_page_bit);
int wait_on_page_bit_killable(struct page *page, int bit_nr) { DEFINE_WAIT_BIT(wait, &page->flags, bit_nr); if (!test_bit(bit_nr, &page->flags)) return 0; return __wait_on_bit(page_waitqueue(page), &wait, bit_wait_io, TASK_KILLABLE); }

Contributors

PersonTokensPropCommitsCommitProp
william lee irwin iiiwilliam lee irwin iii2136.84%114.29%
linus torvaldslinus torvalds1628.07%114.29%
andrew mortonandrew morton1017.54%342.86%
kosaki motohirokosaki motohiro915.79%114.29%
neil brownneil brown11.75%114.29%
Total57100.00%7100.00%


int wait_on_page_bit_killable_timeout(struct page *page, int bit_nr, unsigned long timeout) { DEFINE_WAIT_BIT(wait, &page->flags, bit_nr); wait.key.timeout = jiffies + timeout; if (!test_bit(bit_nr, &page->flags)) return 0; return __wait_on_bit(page_waitqueue(page), &wait, bit_wait_io_timeout, TASK_KILLABLE); }

Contributors

PersonTokensPropCommitsCommitProp
kosaki motohirokosaki motohiro5577.46%150.00%
neil brownneil brown1622.54%150.00%
Total71100.00%2100.00%

EXPORT_SYMBOL_GPL(wait_on_page_bit_killable_timeout); /** * add_page_wait_queue - Add an arbitrary waiter to a page's wait queue * @page: Page defining the wait queue of interest * @waiter: Waiter to add to the queue * * Add an arbitrary @waiter to the wait queue for the nominated @page. */
void add_page_wait_queue(struct page *page, wait_queue_t *waiter) { wait_queue_head_t *q = page_waitqueue(page); unsigned long flags; spin_lock_irqsave(&q->lock, flags); __add_wait_queue(q, waiter); spin_unlock_irqrestore(&q->lock, flags); }

Contributors

PersonTokensPropCommitsCommitProp
david howellsdavid howells54100.00%1100.00%
Total54100.00%1100.00%

EXPORT_SYMBOL_GPL(add_page_wait_queue); /** * unlock_page - unlock a locked page * @page: the page * * Unlocks the page and wakes up sleepers in ___wait_on_page_locked(). * Also wakes sleepers in wait_on_page_writeback() because the wakeup * mechanism between PageLocked pages and PageWriteback pages is shared. * But that's OK - sleepers in wait_on_page_writeback() just go back to sleep. * * The mb is necessary to enforce ordering between the clear_bit and the read * of the waitqueue (to avoid SMP races with a parallel wait_on_page_locked()). */
void unlock_page(struct page *page) { page = compound_head(page); VM_BUG_ON_PAGE(!PageLocked(page), page); clear_bit_unlock(PG_locked, &page->flags); smp_mb__after_atomic(); wake_up_page(page, PG_locked); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds1939.58%111.11%
nick pigginnick piggin1327.08%222.22%
kirill a. shutemovkirill a. shutemov714.58%111.11%
william lee irwin iiiwilliam lee irwin iii48.33%222.22%
sasha levinsasha levin36.25%111.11%
peter zijlstrapeter zijlstra12.08%111.11%
andrew mortonandrew morton12.08%111.11%
Total48100.00%9100.00%

EXPORT_SYMBOL(unlock_page); /** * end_page_writeback - end writeback against a page * @page: the page */
void end_page_writeback(struct page *page) { /* * TestClearPageReclaim could be used here but it is an atomic * operation and overkill in this particular case. Failing to * shuffle a page marked for immediate reclaim is too mild to * justify taking an atomic operation penalty at the end of * ever page writeback. */ if (PageReclaim(page)) { ClearPageReclaim(page); rotate_reclaimable_page(page); } if (!test_clear_page_writeback(page)) BUG(); smp_mb__after_atomic(); wake_up_page(page, PG_writeback); }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton3568.63%444.44%
mel gormanmel gorman917.65%111.11%
william lee irwin iiiwilliam lee irwin iii47.84%222.22%
miklos szeredimiklos szeredi23.92%111.11%
peter zijlstrapeter zijlstra11.96%111.11%
Total51100.00%9100.00%

EXPORT_SYMBOL(end_page_writeback); /* * After completing I/O on a page, call this routine to update the page * flags appropriately */
void page_endio(struct page *page, bool is_write, int err) { if (!is_write) { if (!err) { SetPageUptodate(page); } else { ClearPageUptodate(page); SetPageError(page); } unlock_page(page); } else { if (err) { SetPageError(page); if (page->mapping) mapping_set_error(page->mapping, err); } end_page_writeback(page); } }

Contributors

PersonTokensPropCommitsCommitProp
matthew wilcoxmatthew wilcox8395.40%133.33%
jens axboejens axboe33.45%133.33%
michael christiemichael christie11.15%133.33%
Total87100.00%3100.00%

EXPORT_SYMBOL_GPL(page_endio); /** * __lock_page - get a lock on the page, assuming we need to sleep to get it * @page: the page to lock */
void __lock_page(struct page *page) { struct page *page_head = compound_head(page); DEFINE_WAIT_BIT(wait, &page_head->flags, PG_locked); __wait_on_bit_lock(page_waitqueue(page_head), &wait, bit_wait_io, TASK_UNINTERRUPTIBLE); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds1940.43%114.29%
kirill a. shutemovkirill a. shutemov1225.53%114.29%
william lee irwin iiiwilliam lee irwin iii919.15%228.57%
andrew mortonandrew morton612.77%228.57%
neil brownneil brown12.13%114.29%
Total47100.00%7100.00%

EXPORT_SYMBOL(__lock_page);
int __lock_page_killable(struct page *page) { struct page *page_head = compound_head(page); DEFINE_WAIT_BIT(wait, &page_head->flags, PG_locked); return __wait_on_bit_lock(page_waitqueue(page_head), &wait, bit_wait_io, TASK_KILLABLE); }

Contributors

PersonTokensPropCommitsCommitProp
matthew wilcoxmatthew wilcox3572.92%133.33%
kirill a. shutemovkirill a. shutemov1225.00%133.33%
neil brownneil brown12.08%133.33%
Total48100.00%3100.00%

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) { if (flags & FAULT_FLAG_ALLOW_RETRY) { /* * CAUTION! In this case, mmap_sem is not released * even though return 0. */ if (flags & FAULT_FLAG_RETRY_NOWAIT) return 0; up_read(&mm->mmap_sem); if (flags & FAULT_FLAG_KILLABLE) wait_on_page_locked_killable(page); else wait_on_page_locked(page); return 0; } else { if (flags & FAULT_FLAG_KILLABLE) { int ret; ret = __lock_page_killable(page); if (ret) { up_read(&mm->mmap_sem); return 0; } } else __lock_page(page); return 1; } }

Contributors

PersonTokensPropCommitsCommitProp
kosaki motohirokosaki motohiro5650.00%133.33%
michel lespinassemichel lespinasse5044.64%133.33%
gleb natapovgleb natapov65.36%133.33%
Total112100.00%3100.00%

/** * page_cache_next_hole - find the next hole (not-present entry) * @mapping: mapping * @index: index * @max_scan: maximum range to search * * Search the set [index, min(index+max_scan-1, MAX_INDEX)] for the * lowest indexed hole. * * Returns: the index of the hole if found, otherwise returns an index * outside of the set specified (in which case 'return - index >= * max_scan' will be true). In rare cases of index wrap-around, 0 will * be returned. * * page_cache_next_hole may be called under rcu_read_lock. However, * like radix_tree_gang_lookup, this will not atomically search a * snapshot of the tree at a single point in time. For example, if a * hole is created at index 5, then subsequently a hole is created at * index 10, page_cache_next_hole covering both indexes may return 10 * if called under rcu_read_lock. */
pgoff_t page_cache_next_hole(struct address_space *mapping, pgoff_t index, unsigned long max_scan) { unsigned long i; for (i = 0; i < max_scan; i++) { struct page *page; page = radix_tree_lookup(&mapping->page_tree, index); if (!page || radix_tree_exceptional_entry(page)) break; index++; if (index == 0) break; } return index; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner77100.00%2100.00%
Total77100.00%2100.00%

EXPORT_SYMBOL(page_cache_next_hole); /** * page_cache_prev_hole - find the prev hole (not-present entry) * @mapping: mapping * @index: index * @max_scan: maximum range to search * * Search backwards in the range [max(index-max_scan+1, 0), index] for * the first hole. * * Returns: the index of the hole if found, otherwise returns an index * outside of the set specified (in which case 'index - return >= * max_scan' will be true). In rare cases of wrap-around, ULONG_MAX * will be returned. * * page_cache_prev_hole may be called under rcu_read_lock. However, * like radix_tree_gang_lookup, this will not atomically search a * snapshot of the tree at a single point in time. For example, if a * hole is created at index 10, then subsequently a hole is created at * index 5, page_cache_prev_hole covering both indexes may return 5 if * called under rcu_read_lock. */
pgoff_t page_cache_prev_hole(struct address_space *mapping, pgoff_t index, unsigned long max_scan) { unsigned long i; for (i = 0; i < max_scan; i++) { struct page *page; page = radix_tree_lookup(&mapping->page_tree, index); if (!page || radix_tree_exceptional_entry(page)) break; index--; if (index == ULONG_MAX) break; } return index; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner77100.00%2100.00%
Total77100.00%2100.00%

EXPORT_SYMBOL(page_cache_prev_hole); /** * find_get_entry - find and get a page cache entry * @mapping: the address_space to search * @offset: the page cache index * * Looks up the page cache slot at @mapping & @offset. If there is a * page cache page, it is returned with an increased refcount. * * If the slot holds a shadow entry of a previously evicted page, or a * swap entry from shmem/tmpfs, it is returned. * * Otherwise, %NULL is returned. */
struct page *find_get_entry(struct address_space *mapping, pgoff_t offset) { void **pagep; struct page *head, *page; rcu_read_lock(); repeat: page = NULL; pagep = radix_tree_lookup_slot(&mapping->page_tree, offset); if (pagep) { page = radix_tree_deref_slot(pagep); if (unlikely(!page)) goto out; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) goto repeat; /* * A shadow entry of a recently evicted page, * or a swap entry from shmem/tmpfs. Return * it without attempting to raise page count. */ goto out; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* * Has the page moved? * This is part of the lockless pagecache protocol. See * include/linux/pagemap.h for details. */ if (unlikely(page != *pagep)) { put_page(head); goto repeat; } } out: rcu_read_unlock(); return page; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin7143.56%218.18%
linus torvaldslinus torvalds4024.54%19.09%
kirill a. shutemovkirill a. shutemov3219.63%218.18%
hugh dickinshugh dickins148.59%218.18%
andrew mortonandrew morton31.84%19.09%
johannes weinerjohannes weiner21.23%218.18%
wu fengguangwu fengguang10.61%19.09%
Total163100.00%11100.00%

EXPORT_SYMBOL(find_get_entry); /** * find_lock_entry - locate, pin and lock a page cache entry * @mapping: the address_space to search * @offset: the page cache index * * Looks up the page cache slot at @mapping & @offset. If there is a * page cache page, it is returned locked and with an increased * refcount. * * If the slot holds a shadow entry of a previously evicted page, or a * swap entry from shmem/tmpfs, it is returned. * * Otherwise, %NULL is returned. * * find_lock_entry() may sleep. */
struct page *find_lock_entry(struct address_space *mapping, pgoff_t offset) { struct page *page; repeat: page = find_get_entry(mapping, offset); if (page && !radix_tree_exception(page)) { lock_page(page); /* Has the page been truncated? */ if (unlikely(page_mapping(page) != mapping)) { unlock_page(page); put_page(page); goto repeat; } VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page); } return page; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds5762.64%215.38%
nick pigginnick piggin1010.99%215.38%
kirill a. shutemovkirill a. shutemov77.69%215.38%
hugh dickinshugh dickins66.59%17.69%
sasha levinsasha levin33.30%17.69%
nikita danilovnikita danilov33.30%17.69%
johannes weinerjohannes weiner22.20%17.69%
pre-gitpre-git11.10%17.69%
wu fengguangwu fengguang11.10%17.69%
andrew mortonandrew morton11.10%17.69%
Total91100.00%13100.00%

EXPORT_SYMBOL(find_lock_entry); /** * pagecache_get_page - find and get a page reference * @mapping: the address_space to search * @offset: the page index * @fgp_flags: PCG flags * @gfp_mask: gfp mask to use for the page cache data page allocation * * Looks up the page cache slot at @mapping & @offset. * * PCG flags modify how the page is returned. * * FGP_ACCESSED: the page will be marked accessed * FGP_LOCK: Page is return locked * FGP_CREAT: If page is not present then a new page is allocated using * @gfp_mask and added to the page cache and the VM's LRU * list. The page is returned locked and with an increased * refcount. Otherwise, %NULL is returned. * * If FGP_LOCK or FGP_CREAT are specified then the function may sleep even * if the GFP flags specified for FGP_CREAT are atomic. * * If there is a page cache page, it is returned with an increased refcount. */
struct page *pagecache_get_page(struct address_space *mapping, pgoff_t offset, int fgp_flags, gfp_t gfp_mask) { struct page *page; repeat: page = find_get_entry(mapping, offset); if (radix_tree_exceptional_entry(page)) page = NULL; if (!page) goto no_page; if (fgp_flags & FGP_LOCK) { if (fgp_flags & FGP_NOWAIT) { if (!trylock_page(page)) { put_page(page); return NULL; } } else { lock_page(page); } /* Has the page been truncated? */ if (unlikely(page->mapping != mapping)) { unlock_page(page); put_page(page); goto repeat; } VM_BUG_ON_PAGE(page->index != offset, page); } if (page && (fgp_flags & FGP_ACCESSED)) mark_page_accessed(page); no_page: if (!page && (fgp_flags & FGP_CREAT)) { int err; if ((fgp_flags & FGP_WRITE) && mapping_cap_account_dirty(mapping)) gfp_mask |= __GFP_WRITE; if (fgp_flags & FGP_NOFS) gfp_mask &= ~__GFP_FS; page = __page_cache_alloc(gfp_mask); if (!page) return NULL; if (WARN_ON_ONCE(!(fgp_flags & FGP_LOCK))) fgp_flags |= FGP_LOCK; /* Init accessed so avoid atomic mark_page_accessed later */ if (fgp_flags & FGP_ACCESSED) __SetPageReferenced(page); err = add_to_page_cache_lru(page, mapping, offset, gfp_mask & GFP_RECLAIM_MASK); if (unlikely(err)) { put_page(page); page = NULL; if (err == -EEXIST) goto repeat; } } return page; }

Contributors

PersonTokensPropCommitsCommitProp
mel gormanmel gorman16356.99%16.25%
johannes weinerjohannes weiner3612.59%16.25%
linus torvaldslinus torvalds3512.24%318.75%
andrew mortonandrew morton248.39%425.00%
nick pigginnick piggin103.50%16.25%
michal hockomichal hocko72.45%16.25%
arnaldo carvalho de meloarnaldo carvalho de melo31.05%16.25%
kirill a. shutemovkirill a. shutemov31.05%16.25%
hugh dickinshugh dickins20.70%16.25%
pre-gitpre-git20.70%16.25%
christoph lameterchristoph lameter10.35%16.25%
Total286100.00%16100.00%

EXPORT_SYMBOL(pagecache_get_page); /** * find_get_entries - gang pagecache lookup * @mapping: The address_space to search * @start: The starting page cache index * @nr_entries: The maximum number of entries * @entries: Where the resulting entries are placed * @indices: The cache indices corresponding to the entries in @entries * * find_get_entries() will search for and return a group of up to * @nr_entries entries in the mapping. The entries are placed at * @entries. find_get_entries() takes a reference against any actual * pages it returns. * * The search returns a group of mapping-contiguous page cache entries * with ascending indexes. There may be holes in the indices due to * not-present pages. * * Any shadow entries of evicted pages, or swap entries from * shmem/tmpfs, are included in the returned array. * * find_get_entries() returns the number of pages and shadow entries * which were found. */
unsigned find_get_entries(struct address_space *mapping, pgoff_t start, unsigned int nr_entries, struct page **entries, pgoff_t *indices) { void **slot; unsigned int ret = 0; struct radix_tree_iter iter; if (!nr_entries) return 0; rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) continue; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } /* * A shadow entry of a recently evicted page, a swap * entry from shmem/tmpfs or a DAX entry. Return it * without attempting to raise page count. */ goto export; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } export: indices[ret] = iter.index; entries[ret] = page; if (++ret == nr_entries) break; } rcu_read_unlock(); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
johannes weinerjohannes weiner16979.34%120.00%
kirill a. shutemovkirill a. shutemov3215.02%240.00%
matthew wilcoxmatthew wilcox115.16%120.00%
ross zwislerross zwisler10.47%120.00%
Total213100.00%5100.00%

/** * find_get_pages - gang pagecache lookup * @mapping: The address_space to search * @start: The starting page index * @nr_pages: The maximum number of pages * @pages: Where the resulting pages are placed * * find_get_pages() will search for and return a group of up to * @nr_pages pages in the mapping. The pages are placed at @pages. * find_get_pages() takes a reference against the returned pages. * * The search returns a group of mapping-contiguous pages with ascending * indexes. There may be holes in the indices due to not-present pages. * * find_get_pages() returns the number of pages which were found. */
unsigned find_get_pages(struct address_space *mapping, pgoff_t start, unsigned int nr_pages, struct page **pages) { struct radix_tree_iter iter; void **slot; unsigned ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) continue; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } /* * A shadow entry of a recently evicted page, * or a swap entry from shmem/tmpfs. Skip * over it. */ continue; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } pages[ret] = page; if (++ret == nr_pages) break; } rcu_read_unlock(); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin6934.85%215.38%
andrew mortonandrew morton4020.20%215.38%
konstantin khlebnikovkonstantin khlebnikov3417.17%17.69%
kirill a. shutemovkirill a. shutemov3216.16%215.38%
hugh dickinshugh dickins178.59%430.77%
matthew wilcoxmatthew wilcox52.53%17.69%
johannes weinerjohannes weiner10.51%17.69%
Total198100.00%13100.00%

/** * find_get_pages_contig - gang contiguous pagecache lookup * @mapping: The address_space to search * @index: The starting page index * @nr_pages: The maximum number of pages * @pages: Where the resulting pages are placed * * find_get_pages_contig() works exactly like find_get_pages(), except * that the returned number of pages are guaranteed to be contiguous. * * find_get_pages_contig() returns the number of pages which were found. */
unsigned find_get_pages_contig(struct address_space *mapping, pgoff_t index, unsigned int nr_pages, struct page **pages) { struct radix_tree_iter iter; void **slot; unsigned int ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); radix_tree_for_each_contig(slot, &mapping->page_tree, &iter, index) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); /* The hole, there no reason to continue */ if (unlikely(!page)) break; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } /* * A shadow entry of a recently evicted page, * or a swap entry from shmem/tmpfs. Stop * looking for contiguous pages. */ break; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } /* * must check mapping and index after taking the ref. * otherwise we can get both false positives and false * negatives, which is just confusing to the caller. */ if (page->mapping == NULL || page_to_pgoff(page) != iter.index) { put_page(page); break; } pages[ret] = page; if (++ret == nr_pages) break; } rcu_read_unlock(); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin8838.94%218.18%
konstantin khlebnikovkonstantin khlebnikov3917.26%19.09%
jens axboejens axboe3917.26%19.09%
kirill a. shutemovkirill a. shutemov3615.93%218.18%
hugh dickinshugh dickins146.19%327.27%
matthew wilcoxmatthew wilcox93.98%19.09%
johannes weinerjohannes weiner10.44%19.09%
Total226100.00%11100.00%

EXPORT_SYMBOL(find_get_pages_contig); /** * find_get_pages_tag - find and return pages that match @tag * @mapping: the address_space to search * @index: the starting page index * @tag: the tag index * @nr_pages: the maximum number of pages * @pages: where the resulting pages are placed * * Like find_get_pages, except we only return pages which are tagged with * @tag. We update @index to index the next page for the traversal. */
unsigned find_get_pages_tag(struct address_space *mapping, pgoff_t *index, int tag, unsigned int nr_pages, struct page **pages) { struct radix_tree_iter iter; void **slot; unsigned ret = 0; if (unlikely(!nr_pages)) return 0; rcu_read_lock(); radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, *index, tag) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) continue; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } /* * A shadow entry of a recently evicted page. * * Those entries should never be tagged, but * this tree walk is lockless and the tags are * looked up in bulk, one radix tree node at a * time, so there is a sizable window for page * reclaim to evict a page we saw tagged. * * Skip over it. */ continue; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } pages[ret] = page; if (++ret == nr_pages) break; } rcu_read_unlock(); if (ret) *index = pages[ret - 1]->index + 1; return ret; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin6931.08%19.09%
andrew mortonandrew morton6027.03%218.18%
konstantin khlebnikovkonstantin khlebnikov3415.32%19.09%
kirill a. shutemovkirill a. shutemov3214.41%218.18%
hugh dickinshugh dickins167.21%327.27%
matthew wilcoxmatthew wilcox94.05%19.09%
johannes weinerjohannes weiner20.90%19.09%
Total222100.00%11100.00%

EXPORT_SYMBOL(find_get_pages_tag); /** * find_get_entries_tag - find and return entries that match @tag * @mapping: the address_space to search * @start: the starting page cache index * @tag: the tag index * @nr_entries: the maximum number of entries * @entries: where the resulting entries are placed * @indices: the cache indices corresponding to the entries in @entries * * Like find_get_entries, except we only return entries which are tagged with * @tag. */
unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start, int tag, unsigned int nr_entries, struct page **entries, pgoff_t *indices) { void **slot; unsigned int ret = 0; struct radix_tree_iter iter; if (!nr_entries) return 0; rcu_read_lock(); radix_tree_for_each_tagged(slot, &mapping->page_tree, &iter, start, tag) { struct page *head, *page; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) continue; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } /* * A shadow entry of a recently evicted page, a swap * entry from shmem/tmpfs or a DAX entry. Return it * without attempting to raise page count. */ goto export; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } export: indices[ret] = iter.index; entries[ret] = page; if (++ret == nr_entries) break; } rcu_read_unlock(); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
ross zwislerross zwisler17781.19%125.00%
kirill a. shutemovkirill a. shutemov3214.68%250.00%
matthew wilcoxmatthew wilcox94.13%125.00%
Total218100.00%4100.00%

EXPORT_SYMBOL(find_get_entries_tag); /* * CD/DVDs are error prone. When a medium error occurs, the driver may fail * a _large_ part of the i/o request. Imagine the worst scenario: * * ---R__________________________________________B__________ * ^ reading here ^ bad block(assume 4k) * * read(R) => miss => readahead(R...B) => media error => frustrating retries * => failing the whole request => read(R) => read(R+1) => * readahead(R+1...B+1) => bang => read(R+2) => read(R+3) => * readahead(R+3...B+2) => bang => read(R+3) => read(R+4) => * readahead(R+4...B+3) => bang => read(R+4) => read(R+5) => ...... * * It is going insane. Fix it by quickly scaling down the readahead size. */
static void shrink_readahead_size_eio(struct file *filp, struct file_ra_state *ra) { ra->ra_pages /= 4; }

Contributors

PersonTokensPropCommitsCommitProp
wu fengguangwu fengguang22100.00%1100.00%
Total22100.00%1100.00%

/** * do_generic_file_read - generic file read routine * @filp: the file to read * @ppos: current file position * @iter: data destination * @written: already copied * * This is a generic file read routine, and uses the * mapping->a_ops->readpage() function for the actual low-level stuff. * * This is really ugly. But the goto's actually try to clarify some * of the logic when it comes to error handling etc. */
static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos, struct iov_iter *iter, ssize_t written) { struct address_space *mapping = filp->f_mapping; struct inode *inode = mapping->host; struct file_ra_state *ra = &filp->f_ra; pgoff_t index; pgoff_t last_index; pgoff_t prev_index; unsigned long offset; /* offset into pagecache page */ unsigned int prev_offset; int error = 0; index = *ppos >> PAGE_SHIFT; prev_index = ra->prev_pos >> PAGE_SHIFT; prev_offset = ra->prev_pos & (PAGE_SIZE-1); last_index = (*ppos + iter->count + PAGE_SIZE-1) >> PAGE_SHIFT; offset = *ppos & ~PAGE_MASK; for (;;) { struct page *page; pgoff_t end_index; loff_t isize; unsigned long nr, ret; cond_resched(); find_page: page = find_get_page(mapping, index); if (!page) { page_cache_sync_readahead(mapping, ra, filp, index, last_index - index); page = find_get_page(mapping, index); if (unlikely(page == NULL)) goto no_cached_page; } if (PageReadahead(page)) { page_cache_async_readahead(mapping, ra, filp, page, index, last_index - index); } if (!PageUptodate(page)) { /* * See comment in do_read_cache_page on why * wait_on_page_locked is used to avoid unnecessarily * serialisations and why it's safe. */ wait_on_page_locked_killable(page); if (PageUptodate(page)) goto page_ok; if (inode->i_blkbits == PAGE_SHIFT || !mapping->a_ops->is_partially_uptodate) goto page_not_up_to_date; if (!trylock_page(page)) goto page_not_up_to_date; /* Did it get truncated before we got the lock? */ if (!page->mapping) goto page_not_up_to_date_locked; if (!mapping->a_ops->is_partially_uptodate(page, offset, iter->count)) goto page_not_up_to_date_locked; unlock_page(page); } page_ok: /* * i_size must be checked after we know the page is Uptodate. * * Checking i_size after the check allows us to calculate * the correct value for "nr", which means the zero-filled * part of the page is not copied back to userspace (unless * another truncate extends the file - this is desired though). */ isize = i_size_read(inode); end_index = (isize - 1) >> PAGE_SHIFT; if (unlikely(!isize || index > end_index)) { put_page(page); goto out; } /* nr is the maximum number of bytes to copy from this page */ nr = PAGE_SIZE; if (index == end_index) { nr = ((isize - 1) & ~PAGE_MASK) + 1; if (nr <= offset) { put_page(page); goto out; } } nr = nr - offset; /* If users can be writing to this page using arbitrary * virtual addresses, take care about potential aliasing * before reading the page on the kernel side. */ if (mapping_writably_mapped(mapping)) flush_dcache_page(page); /* * When a sequential read accesses a page several times, * only mark it as accessed the first time. */ if (prev_index != index || offset != prev_offset) mark_page_accessed(page); prev_index = index; /* * Ok, we have the page, and it's up-to-date, so * now we can copy it to user space... */ ret = copy_page_to_iter(page, offset, nr, iter); offset += ret; index += offset >> PAGE_SHIFT; offset &= ~PAGE_MASK; prev_offset = offset; put_page(page); written += ret; if (!iov_iter_count(iter)) goto out; if (ret < nr) { error = -EFAULT; goto out; } continue; page_not_up_to_date: /* Get exclusive access to the page ... */ error = lock_page_killable(page); if (unlikely(error)) goto readpage_error; page_not_up_to_date_locked: /* Did it get truncated before we got the lock? */ if (!page->mapping) { unlock_page(page); put_page(page); continue; } /* Did somebody else fill it already? */ if (PageUptodate(page)) { unlock_page(page); goto page_ok; } readpage: /* * A previous I/O error may have been due to temporary * failures, eg. multipath errors. * PG_error will be set again if readpage fails. */ ClearPageError(page); /* Start the actual read. The read will unlock the page. */ error = mapping->a_ops->readpage(filp, page); if (unlikely(error)) { if (error == AOP_TRUNCATED_PAGE) { put_page(page); error = 0; goto find_page; } goto readpage_error; } if (!PageUptodate(page)) { error = lock_page_killable(page); if (unlikely(error)) goto readpage_error; if (!PageUptodate(page)) { if (page->mapping == NULL) { /* * invalidate_mapping_pages got it */ unlock_page(page); put_page(page); goto find_page; } unlock_page(page); shrink_readahead_size_eio(filp, ra); error = -EIO; goto readpage_error; } unlock_page(page); } goto page_ok; readpage_error: /* UHHUH! A synchronous read error occurred. Report it */ put_page(page); goto out; no_cached_page: /* * Ok, it wasn't cached, so we need to create a new * page.. */ page = page_cache_alloc_cold(mapping); if (!page) { error = -ENOMEM; goto out; } error = add_to_page_cache_lru(page, mapping, index, mapping_gfp_constraint(mapping, GFP_KERNEL)); if (error) { put_page(page); if (error == -EEXIST) { error = 0; goto find_page; } goto out; } goto readpage; } out: ra->prev_pos = prev_index; ra->prev_pos <<= PAGE_SHIFT; ra->prev_pos |= prev_offset; *ppos = ((loff_t)index << PAGE_SHIFT) + offset; file_accessed(filp); return written ? written : error; }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds14516.92%46.45%
andrew mortonandrew morton13715.99%1422.58%
neil brownneil brown9210.74%11.61%
wu fengguangwu fengguang748.63%58.06%
al viroal viro586.77%46.45%
nick pigginnick piggin576.65%46.45%
pre-gitpre-git515.95%1016.13%
hisashi hifumihisashi hifumi495.72%11.61%
oleg nesterovoleg nesterov343.97%23.23%
christoph hellwigchristoph hellwig222.57%23.23%
kirill a. shutemovkirill a. shutemov222.57%11.61%
steven prattsteven pratt182.10%11.61%
jan karajan kara171.98%23.23%
zach brownzach brown171.98%11.61%
mel gormanmel gorman161.87%11.61%
miquel van smoorenburgmiquel van smoorenburg121.40%23.23%
dave hansendave hansen111.28%11.61%
matthew wilcoxmatthew wilcox80.93%11.61%
jeff moyerjeff moyer60.70%11.61%
michal hockomichal hocko60.70%23.23%
david howellsdavid howells30.35%11.61%
rusty russellrusty russell20.23%11.61%
Total857100.00%62100.00%

/** * generic_file_read_iter - generic filesystem read routine * @iocb: kernel I/O control block * @iter: destination for the data read * * This is the "read_iter()" routine for all filesystems * that can use the page cache directly. */
ssize_t generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; ssize_t retval = 0; size_t count = iov_iter_count(iter); if (!count) goto out; /* skip atime */ if (iocb->ki_flags & IOCB_DIRECT) { struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; loff_t size; size = i_size_read(inode); retval = filemap_write_and_wait_range(mapping, iocb->ki_pos, iocb->ki_pos + count - 1); if (!retval) { struct iov_iter data = *iter; retval = mapping->a_ops->direct_IO(iocb, &data); } if (retval > 0) { iocb->ki_pos += retval; iov_iter_advance(iter, retval); } /* * Btrfs can have a short DIO read if we encounter * compressed extents, so if there was an error, or if * we've already read everything we wanted to, or if * there was a short read because we hit EOF, go ahead * and return. Otherwise fallthrough to buffered io for * the rest of the read. Buffered reads will not work for * DAX files, so don't bother trying. */ if (retval < 0 || !iov_iter_count(iter) || iocb->ki_pos >= size || IS_DAX(inode)) { file_accessed(file); goto out; } } retval = do_generic_file_read(file, &iocb->ki_pos, iter, retval); out: return retval; }

Contributors

PersonTokensPropCommitsCommitProp
al viroal viro4722.71%832.00%
linus torvaldslinus torvalds3516.91%28.00%
christoph hellwigchristoph hellwig3516.91%28.00%
dmitriy monakhovdmitriy monakhov2110.14%14.00%
andrew mortonandrew morton199.18%416.00%
nicolai stangenicolai stange178.21%14.00%
josef bacikjosef bacik136.28%14.00%
steven whitehousesteven whitehouse62.90%28.00%
matthew wilcoxmatthew wilcox62.90%14.00%
nick pigginnick piggin62.90%14.00%
suparna bhattacharyasuparna bhattacharya10.48%14.00%
pre-gitpre-git10.48%14.00%
Total207100.00%25100.00%

EXPORT_SYMBOL(generic_file_read_iter); #ifdef CONFIG_MMU /** * page_cache_read - adds requested page to the page cache if not already there * @file: file to read * @offset: page index * @gfp_mask: memory allocation flags * * This adds the requested page to the page cache if it isn't already there, * and schedules an I/O to read in its contents from disk. */
static int page_cache_read(struct file *file, pgoff_t offset, gfp_t gfp_mask) { struct address_space *mapping = file->f_mapping; struct page *page; int ret; do { page = __page_cache_alloc(gfp_mask|__GFP_COLD); if (!page) return -ENOMEM; ret = add_to_page_cache_lru(page, mapping, offset, gfp_mask & GFP_KERNEL); if (ret == 0) ret = mapping->a_ops->readpage(file, page); else if (ret == -EEXIST) ret = 0; /* losing race to add is OK */ put_page(page); } while (ret == AOP_TRUNCATED_PAGE); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
christoph hellwigchristoph hellwig7362.39%111.11%
zach brownzach brown2924.79%111.11%
michal hockomichal hocko119.40%333.33%
andrew mortonandrew morton21.71%222.22%
kirill a. shutemovkirill a. shutemov10.85%111.11%
wu fengguangwu fengguang10.85%111.11%
Total117100.00%9100.00%

#define MMAP_LOTSAMISS (100) /* * Synchronous readahead happens when we don't even find * a page in the page cache at all. */
static void do_sync_mmap_readahead(struct vm_area_struct *vma, struct file_ra_state *ra, struct file *file, pgoff_t offset) { struct address_space *mapping = file->f_mapping; /* If we don't want any read-ahead, don't bother */ if (vma->vm_flags & VM_RAND_READ) return; if (!ra->ra_pages) return; if (vma->vm_flags & VM_SEQ_READ) { page_cache_sync_readahead(mapping, ra, file, offset, ra->ra_pages); return; } /* Avoid banging the cache line if not needed */ if (ra->mmap_miss < MMAP_LOTSAMISS * 10) ra->mmap_miss++; /* * Do we miss much more than hit in this file? If so, * stop bothering with read-ahead. It will only hurt. */ if (ra->mmap_miss > MMAP_LOTSAMISS) return; /* * mmap read-around */ ra->start = max_t(long, 0, offset - ra->ra_pages / 2); ra->size = ra->ra_pages; ra->async_size = ra->ra_pages / 4; ra_submit(ra, mapping, file); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds9563.33%112.50%
fengguang wufengguang wu3724.67%450.00%
joe perchesjoe perches85.33%112.50%
roman gushchinroman gushchin64.00%112.50%
andi kleenandi kleen42.67%112.50%
Total150100.00%8100.00%

/* * Asynchronous readahead happens when we find the page and PG_readahead, * so we want to possibly extend the readahead further.. */
static void do_async_mmap_readahead(struct vm_area_struct *vma, struct file_ra_state *ra, struct file *file, struct page *page, pgoff_t offset) { struct address_space *mapping = file->f_mapping; /* If we don't want any read-ahead, don't bother */ if (vma->vm_flags & VM_RAND_READ) return; if (ra->mmap_miss > 0) ra->mmap_miss--; if (PageReadahead(page)) page_cache_async_readahead(mapping, ra, file, page, offset, ra->ra_pages); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds7891.76%133.33%
joe perchesjoe perches44.71%133.33%
fengguang wufengguang wu33.53%133.33%
Total85100.00%3100.00%

/** * filemap_fault - read in file data for page fault handling * @vma: vma in which the fault was taken * @vmf: struct vm_fault containing details of the fault * * filemap_fault() is invoked via the vma operations vector for a * mapped memory region to read in file data during a page fault. * * 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) { int error; struct file *file = vma->vm_file; struct address_space *mapping = file->f_mapping; struct file_ra_state *ra = &file->f_ra; struct inode *inode = mapping->host; pgoff_t offset = vmf->pgoff; struct page *page; loff_t size; int ret = 0; size = round_up(i_size_read(inode), PAGE_SIZE); if (offset >= size >> PAGE_SHIFT) return VM_FAULT_SIGBUS; /* * Do we have something in the page cache already? */ page = find_get_page(mapping, offset); if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) { /* * We found the page, so try async readahead before * waiting for the lock. */ do_async_mmap_readahead(vma, ra, file, page, offset); } else if (!page) { /* No page in the page cache at all */ do_sync_mmap_readahead(vma, ra, file, offset); count_vm_event(PGMAJFAULT); mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT); ret = VM_FAULT_MAJOR; retry_find: page = find_get_page(mapping, offset); if (!page) goto no_cached_page; } if (!lock_page_or_retry(page, vma->vm_mm, vmf->flags)) { put_page(page); return ret | VM_FAULT_RETRY; } /* Did it get truncated? */ if (unlikely(page->mapping != mapping)) { unlock_page(page); put_page(page); goto retry_find; } VM_BUG_ON_PAGE(page->index != offset, page); /* * We have a locked page in the page cache, now we need to check * that it's up-to-date. If not, it is going to be due to an error. */ if (unlikely(!PageUptodate(page))) goto page_not_uptodate; /* * Found the page and have a reference on it. * We must recheck i_size under page lock. */ size = round_up(i_size_read(inode), PAGE_SIZE); if (unlikely(offset >= size >> PAGE_SHIFT)) { unlock_page(page); put_page(page); return VM_FAULT_SIGBUS; } vmf->page = page; return ret | VM_FAULT_LOCKED; no_cached_page: /* * We're only likely to ever get here if MADV_RANDOM is in * effect. */ error = page_cache_read(file, offset, vmf->gfp_mask); /* * The page we want has now been added to the page cache. * In the unlikely event that someone removed it in the * meantime, we'll just come back here and read it again. */ if (error >= 0) goto retry_find; /* * An error return from page_cache_read can result if the * system is low on memory, or a problem occurs while trying * to schedule I/O. */ if (error == -ENOMEM) return VM_FAULT_OOM; return VM_FAULT_SIGBUS; page_not_uptodate: /* * Umm, take care of errors if the page isn't up-to-date. * Try to re-read it _once_. We do this synchronously, * because there really aren't any performance issues here * and we need to check for errors. */ ClearPageError(page); error = mapping->a_ops->readpage(file, page); if (!error) { wait_on_page_locked(page); if (!PageUptodate(page)) error = -EIO; } put_page(page); if (!error || error == AOP_TRUNCATED_PAGE) goto retry_find; /* Things didn't work out. Return zero to tell the mm layer so. */ shrink_readahead_size_eio(file, ra); return VM_FAULT_SIGBUS; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git10824.43%1732.08%
michel lespinassemichel lespinasse6314.25%35.66%
nick pigginnick piggin5712.90%47.55%
linus torvaldslinus torvalds5612.67%713.21%
andrew mortonandrew morton378.37%815.09%
miklos szeredimiklos szeredi255.66%11.89%
kirill a. shutemovkirill a. shutemov184.07%23.77%
wu fengguangwu fengguang173.85%23.77%
shaohua lishaohua li153.39%11.89%
david howellsdavid howells143.17%11.89%
zach brownzach brown102.26%11.89%
ying hanying han92.04%11.89%
yan zhengyan zheng40.90%11.89%
michal hockomichal hocko40.90%11.89%
sasha levinsasha levin30.68%11.89%
steven prattsteven pratt10.23%11.89%
johannes weinerjohannes weiner10.23%11.89%
Total442100.00%53100.00%

EXPORT_SYMBOL(filemap_fault);
void filemap_map_pages(struct fault_env *fe, pgoff_t start_pgoff, pgoff_t end_pgoff) { struct radix_tree_iter iter; void **slot; struct file *file = fe->vma->vm_file; struct address_space *mapping = file->f_mapping; pgoff_t last_pgoff = start_pgoff; loff_t size; struct page *head, *page; rcu_read_lock(); radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start_pgoff) { if (iter.index > end_pgoff) break; repeat: page = radix_tree_deref_slot(slot); if (unlikely(!page)) goto next; if (radix_tree_exception(page)) { if (radix_tree_deref_retry(page)) { slot = radix_tree_iter_retry(&iter); continue; } goto next; } head = compound_head(page); if (!page_cache_get_speculative(head)) goto repeat; /* The page was split under us? */ if (compound_head(page) != head) { put_page(head); goto repeat; } /* Has the page moved? */ if (unlikely(page != *slot)) { put_page(head); goto repeat; } if (!PageUptodate(page) || PageReadahead(page) || PageHWPoison(page)) goto skip; if (!trylock_page(page)) goto skip; if (page->mapping != mapping || !PageUptodate(page)) goto unlock; size = round_up(i_size_read(mapping->host), PAGE_SIZE); if (page->index >= size >> PAGE_SHIFT) goto unlock; if (file->f_ra.mmap_miss > 0) file->f_ra.mmap_miss--; fe->address += (iter.index - last_pgoff) << PAGE_SHIFT; if (fe->pte) fe->pte += iter.index - last_pgoff; last_pgoff = iter.index; if (alloc_set_pte(fe, NULL, page)) goto unlock; unlock_page(page); goto next; unlock: unlock_page(page); skip: put_page(page); next: /* Huge page is mapped? No need to proceed. */ if (pmd_trans_huge(*fe->pmd)) break; if (iter.index == end_pgoff) break; } rcu_read_unlock(); }

Contributors

PersonTokensPropCommitsCommitProp
kirill a. shutemovkirill a. shutemov37497.14%685.71%
matthew wilcoxmatthew wilcox112.86%114.29%
Total385100.00%7100.00%

EXPORT_SYMBOL(filemap_map_pages);
int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) { struct page *page = vmf->page; struct inode *inode = file_inode(vma->vm_file); int ret = VM_FAULT_LOCKED; sb_start_pagefault(inode->i_sb); file_update_time(vma->vm_file); lock_page(page); if (page->mapping != inode->i_mapping) { unlock_page(page); ret = VM_FAULT_NOPAGE; goto out; } /* * We mark the page dirty already here so that when freeze is in * progress, we are guaranteed that writeback during freezing will * see the dirty page and writeprotect it again. */ set_page_dirty(page); wait_for_stable_page(page); out: sb_end_pagefault(inode->i_sb); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
jan karajan kara9992.52%250.00%
darrick j. wongdarrick j. wong54.67%125.00%
al viroal viro32.80%125.00%
Total107100.00%4100.00%

EXPORT_SYMBOL(filemap_page_mkwrite); const struct vm_operations_struct generic_file_vm_ops = { .fault = filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = filemap_page_mkwrite, }; /* This is used for a general mmap of a disk file */
int generic_file_mmap(struct file * file, struct vm_area_struct * vma) { struct address_space *mapping = file->f_mapping; if (!mapping->a_ops->readpage) return -ENOEXEC; file_accessed(file); vma->vm_ops = &generic_file_vm_ops; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton2446.15%228.57%
nick pigginnick piggin2038.46%114.29%
pre-gitpre-git47.69%228.57%
jeff moyerjeff moyer35.77%114.29%
ingo molnaringo molnar11.92%114.29%
Total52100.00%7100.00%

/* * This is for filesystems which do not implement ->writepage. */
int generic_file_readonly_mmap(struct file *file, struct vm_area_struct *vma) { if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) return -EINVAL; return generic_file_mmap(file, vma); }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton45100.00%2100.00%
Total45100.00%2100.00%

#else
int generic_file_mmap(struct file * file, struct vm_area_struct * vma) { return -ENOSYS; }

Contributors

PersonTokensPropCommitsCommitProp
christoph hellwigchristoph hellwig19100.00%1100.00%
Total19100.00%1100.00%


int generic_file_readonly_mmap(struct file * file, struct vm_area_struct * vma) { return -ENOSYS; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton19100.00%1100.00%
Total19100.00%1100.00%

#endif /* CONFIG_MMU */ EXPORT_SYMBOL(generic_file_mmap); EXPORT_SYMBOL(generic_file_readonly_mmap);
static struct page *wait_on_page_read(struct page *page) { if (!IS_ERR(page)) { wait_on_page_locked(page); if (!PageUptodate(page)) { put_page(page); page = ERR_PTR(-EIO); } } return page; }

Contributors

PersonTokensPropCommitsCommitProp
sasha levinsasha levin5398.15%150.00%
kirill a. shutemovkirill a. shutemov11.85%150.00%
Total54100.00%2100.00%


static struct page *do_read_cache_page(struct address_space *mapping, pgoff_t index, int (*filler)(void *, struct page *), void *data, gfp_t gfp) { struct page *page; int err; repeat: page = find_get_page(mapping, index); if (!page) { page = __page_cache_alloc(gfp | __GFP_COLD); if (!page) return ERR_PTR(-ENOMEM); err = add_to_page_cache_lru(page, mapping, index, gfp); if (unlikely(err)) { put_page(page); if (err == -EEXIST) goto repeat; /* Presumably ENOMEM for radix tree node */ return ERR_PTR(err); } filler: err = filler(data, page); if (err < 0) { put_page(page); return ERR_PTR(err); } page = wait_on_page_read(page); if (IS_ERR(page)) return page; goto out; } if (PageUptodate(page)) goto out; /* * Page is not up to date and may be locked due one of the following * case a: Page is being filled and the page lock is held * case b: Read/write error clearing the page uptodate status * case c: Truncation in progress (page locked) * case d: Reclaim in progress * * Case a, the page will be up to date when the page is unlocked. * There is no need to serialise on the page lock here as the page * is pinned so the lock gives no additional protection. Even if the * the page is truncated, the data is still valid if PageUptodate as * it's a race vs truncate race. * Case b, the page will not be up to date * Case c, the page may be truncated but in itself, the data may still * be valid after IO completes as it's a read vs truncate race. The * operation must restart if the page is not uptodate on unlock but * otherwise serialising on page lock to stabilise the mapping gives * no additional guarantees to the caller as the page lock is * released before return. * Case d, similar to truncation. If reclaim holds the page lock, it * will be a race with remove_mapping that determines if the mapping * is valid on unlock but otherwise the data is valid and there is * no need to serialise with page lock. * * As the page lock gives no additional guarantee, we optimistically * wait on the page to be unlocked and check if it's up to date and * use the page if it is. Otherwise, the page lock is required to * distinguish between the different cases. The motivation is that we * avoid spurious serialisations and wakeups when multiple processes * wait on the same page for IO to complete. */ wait_on_page_locked(page); if (PageUptodate(page)) goto out; /* Distinguish between all the cases under the safety of the lock */ lock_page(page); /* Case c or d, restart the operation */ if (!page->mapping) { unlock_page(page); put_page(page); goto repeat; } /* Someone else locked and filled the page in a very small window */ if (PageUptodate(page)) { unlock_page(page); goto out; } goto filler; out: mark_page_accessed(page); return page; }

Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git15759.47%315.79%
mel gormanmel gorman3111.74%210.53%
nick pigginnick piggin269.85%210.53%
andrew mortonandrew morton238.71%421.05%
linus torvaldslinus torvalds124.55%315.79%
sasha levinsasha levin72.65%15.26%
kirill a. shutemovkirill a. shutemov31.14%15.26%
david howellsdavid howells31.14%15.26%
dave kleikampdave kleikamp10.38%15.26%
wu fengguangwu fengguang10.38%15.26%
Total264100.00%19100.00%

/** * read_cache_page - read into page cache, fill it if needed * @mapping: the page's address_space * @index: the page index * @filler: function to perform the read * @data: first arg to filler(data, page) function, often left as NULL * * Read into the page cache. If a page already exists, and PageUptodate() is * not set, try to fill the page and wait for it to become unlocked. * * If the page does not get brought uptodate, return -EIO. */
struct page *read_cache_page(struct address_space *mapping, pgoff_t index, int (*filler)(void *, struct page *), void *data) { return do_read_cache_page(mapping, index, filler, data, mapping_gfp_mask(mapping)); }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin3876.00%125.00%
linus torvaldslinus torvalds1020.00%125.00%
sasha levinsasha levin12.00%125.00%
wu fengguangwu fengguang12.00%125.00%
Total50100.00%4100.00%

EXPORT_SYMBOL(read_cache_page); /** * read_cache_page_gfp - read into page cache, using specified page allocation flags. * @mapping: the page's address_space * @index: the page index * @gfp: the page allocator flags to use if allocating * * This is the same as "read_mapping_page(mapping, index, NULL)", but with * any new page allocations done using the specified allocation flags. * * If the page does not get brought uptodate, return -EIO. */
struct page *read_cache_page_gfp(struct address_space *mapping, pgoff_t index, gfp_t gfp) { filler_t *filler = (filler_t *)mapping->a_ops->readpage; return do_read_cache_page(mapping, index, filler, NULL, gfp); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds2758.70%133.33%
al viroal viro1226.09%133.33%
nick pigginnick piggin715.22%133.33%
Total46100.00%3100.00%

EXPORT_SYMBOL(read_cache_page_gfp); /* * Performs necessary checks before doing a write * * Can adjust writing position or amount of bytes to write. * Returns appropriate error code that caller should return or * zero in case that write should be allowed. */
inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; unsigned long limit = rlimit(RLIMIT_FSIZE); loff_t pos; if (!iov_iter_count(from)) return 0; /* FIXME: this is for backwards compatibility with 2.4 */ if (iocb->ki_flags & IOCB_APPEND) iocb->ki_pos = i_size_read(inode); pos = iocb->ki_pos; if (limit != RLIM_INFINITY) { if (iocb->ki_pos >= limit) { send_sig(SIGXFSZ, current, 0); return -EFBIG; } iov_iter_truncate(from, limit - (unsigned long)pos); } /* * LFS rule */ if (unlikely(pos + iov_iter_count(from) > MAX_NON_LFS && !(file->f_flags & O_LARGEFILE))) { if (pos >= MAX_NON_LFS) return -EFBIG; iov_iter_truncate(from, MAX_NON_LFS - (unsigned long)pos); } /* * Are we about to exceed the fs block limit ? * * If we have written data it becomes a short write. If we have * exceeded without writing data we send a signal and return EFBIG. * Linus frestrict idea will clean these up nicely.. */ if (unlikely(pos >= inode->i_sb->s_maxbytes)) return -EFBIG; iov_iter_truncate(from, inode->i_sb->s_maxbytes - pos); return iov_iter_count(from); }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin11152.11%18.33%
al viroal viro5726.76%216.67%
linus torvaldslinus torvalds2411.27%325.00%
andrew mortonandrew morton146.57%433.33%
pre-gitpre-git41.88%18.33%
jiri slabyjiri slaby31.41%18.33%
Total213100.00%12100.00%

EXPORT_SYMBOL(generic_write_checks);
int pagecache_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { const struct address_space_operations *aops = mapping->a_ops; return aops->write_begin(file, mapping, pos, len, flags, pagep, fsdata); }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin4569.23%133.33%
andrew mortonandrew morton1523.08%133.33%
christoph hellwigchristoph hellwig57.69%133.33%
Total65100.00%3100.00%

EXPORT_SYMBOL(pagecache_write_begin);
int pagecache_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { const struct address_space_operations *aops = mapping->a_ops; return aops->write_end(file, mapping, pos, len, copied, page, fsdata); }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin5892.06%250.00%
christoph hellwigchristoph hellwig34.76%125.00%
hisashi hifumihisashi hifumi23.17%125.00%
Total63100.00%4100.00%

EXPORT_SYMBOL(pagecache_write_end);
ssize_t generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; loff_t pos = iocb->ki_pos; ssize_t written; size_t write_len; pgoff_t end; struct iov_iter data; write_len = iov_iter_count(from); end = (pos + write_len - 1) >> PAGE_SHIFT; written = filemap_write_and_wait_range(mapping, pos, pos + write_len - 1); if (written) goto out; /* * After a write we want buffered reads to be sure to go to disk to get * the new data. We invalidate clean cached page from the region we're * about to write. We do this *before* the write so that we can return * without clobbering -EIOCBQUEUED from ->direct_IO(). */ if (mapping->nrpages) { written = invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, end); /* * If a page can not be invalidated, return 0 to fall back * to buffered write. */ if (written) { if (written == -EBUSY) return 0; goto out; } } data = *from; written = mapping->a_ops->direct_IO(iocb, &data); /* * Finally, try again to invalidate clean pages which might have been * cached by non-direct readahead, or faulted in by get_user_pages() * if the source of the write was an mmap'ed region of the file * we're writing. Either one is a pretty crazy thing to do, * so we don't support it 100%. If this invalidation * fails, tough, the write still worked... */ if (mapping->nrpages) { invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, end); } if (written > 0) { pos += written; iov_iter_advance(from, written); if (pos > i_size_read(inode) && !S_ISBLK(inode->i_mode)) { i_size_write(inode, pos); mark_inode_dirty(inode); } iocb->ki_pos = pos; } out: return written; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin9940.41%325.00%
christoph hellwigchristoph hellwig9940.41%216.67%
al viroal viro2510.20%433.33%
hisashi hifumihisashi hifumi145.71%18.33%
namhyung kimnamhyung kim52.04%18.33%
kirill a. shutemovkirill a. shutemov31.22%18.33%
Total245100.00%12100.00%

EXPORT_SYMBOL(generic_file_direct_write); /* * Find or create a page at the given pagecache position. Return the locked * page. This function is specifically for buffered writes. */
struct page *grab_cache_page_write_begin(struct address_space *mapping, pgoff_t index, unsigned flags) { struct page *page; int fgp_flags = FGP_LOCK|FGP_WRITE|FGP_CREAT; if (flags & AOP_FLAG_NOFS) fgp_flags |= FGP_NOFS; page = pagecache_get_page(mapping, index, fgp_flags, mapping_gfp_mask(mapping)); if (page) wait_for_stable_page(page); return page; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin4970.00%457.14%
mel gormanmel gorman1622.86%114.29%
darrick j. wongdarrick j. wong57.14%228.57%
Total70100.00%7100.00%

EXPORT_SYMBOL(grab_cache_page_write_begin);
ssize_t generic_perform_write(struct file *file, struct iov_iter *i, loff_t pos) { struct address_space *mapping = file->f_mapping; const struct address_space_operations *a_ops = mapping->a_ops; long status = 0; ssize_t written = 0; unsigned int flags = 0; /* * Copies from kernel address space cannot fail (NFSD is a big user). */ if (!iter_is_iovec(i)) flags |= AOP_FLAG_UNINTERRUPTIBLE; do { struct page *page; unsigned long offset; /* Offset into pagecache page */ unsigned long bytes; /* Bytes to write to page */ size_t copied; /* Bytes copied from user */ void *fsdata; offset = (pos & (PAGE_SIZE - 1)); bytes = min_t(unsigned long, PAGE_SIZE - offset, iov_iter_count(i)); again: /* * Bring in the user page that we will copy from _first_. * Otherwise there's a nasty deadlock on copying from the * same page as we're writing to, without it being marked * up-to-date. * * Not only is this an optimisation, but it is also required * to check that the address is actually valid, when atomic * usercopies are used, below. */ if (unlikely(iov_iter_fault_in_readable(i, bytes))) { status = -EFAULT; break; } if (fatal_signal_pending(current)) { status = -EINTR; break; } status = a_ops->write_begin(file, mapping, pos, bytes, flags, &page, &fsdata); if (unlikely(status < 0)) break; if (mapping_writably_mapped(mapping)) flush_dcache_page(page); copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes); flush_dcache_page(page); status = a_ops->write_end(file, mapping, pos, bytes, copied, page, fsdata); if (unlikely(status < 0)) break; copied = status; cond_resched(); iov_iter_advance(i, copied); if (unlikely(copied == 0)) { /* * If we were unable to copy any data at all, we must * fall back to a single segment length write. * * If we didn't fallback here, we could livelock * because not all segments in the iov can be copied at * once without a pagefault. */ bytes = min_t(unsigned long, PAGE_SIZE - offset, iov_iter_single_seg_count(i)); goto again; } pos += copied; written += copied; balance_dirty_pages_ratelimited(mapping); } while (iov_iter_count(i)); return written ? written : status; }

Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin13442.54%830.77%
christoph hellwigchristoph hellwig8827.94%27.69%
andrew mortonandrew morton319.84%623.08%
linus torvaldslinus torvalds237.30%311.54%
jan karajan kara154.76%13.85%
anfei zhouanfei zhou123.81%13.85%
al viroal viro30.95%13.85%
kirill a. shutemovkirill a. shutemov30.95%13.85%
zach brownzach brown30.95%13.85%
mel gormanmel gorman20.63%13.85%
daniel mcneildaniel mcneil10.32%13.85%
Total315100.00%26100.00%

EXPORT_SYMBOL(generic_perform_write); /** * __generic_file_write_iter - write data to a file * @iocb: IO state structure (file, offset, etc.) * @from: iov_iter with data to write * * This function does all the work needed for actually writing data to a * file. It does all basic checks, removes SUID from the file, updates * modification times and calls proper subroutines depending on whether we * do direct IO or a standard buffered write. * * It expects i_mutex to be grabbed unless we work on a block device or similar * object which does not need locking at all. * * This function does *not* take care of syncing data in case of O_SYNC write. * A caller has to handle it. This is mainly due to the fact that we want to * avoid syncing under i_mutex. */
ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct address_space * mapping = file->f_mapping; struct inode *inode = mapping->host; ssize_t written = 0; ssize_t err; ssize_t status; /* We can write back this queue in page reclaim */ current->backing_dev_info = inode_to_bdi(inode); err = file_remove_privs(file); if (err) goto out; err = file_update_time(file); if (err) goto out; if (iocb->ki_flags & IOCB_DIRECT) { loff_t pos, endbyte; written = generic_file_direct_write(iocb, from); /* * If the write stopped short of completing, fall back to * buffered writes. Some filesystems do this for writes to * holes, for example. For DAX files, a buffered write will * not succeed (even if it did, DAX does not handle dirty * page-cache pages correctly). */ if (written < 0 || !iov_iter_count(from) || IS_DAX(inode)) goto out; status = generic_perform_write(file, from, pos = iocb->ki_pos); /* * If generic_perform_write() returned a synchronous error * then we want to return the number of bytes which were * direct-written, or the error code if that was zero. Note * that this differs from normal direct-io semantics, which * will return -EFOO even if some bytes were written. */ if (unlikely(status < 0)) { err = status; goto out; } /* * We need to ensure that the page cache pages are written to * disk and invalidated to preserve the expected O_DIRECT * semantics. */ endbyte = pos + status - 1; err = filemap_write_and_wait_range(mapping, pos, endbyte); if (err == 0) { iocb->ki_pos = endbyte + 1; written += status; invalidate_mapping_pages(mapping, pos >> PAGE_SHIFT, endbyte >> PAGE_SHIFT); } else { /* * We don't know how much we wrote, so just return * the number of bytes which were direct-written */ } } else { written = generic_perform_write(file, from, iocb->ki_pos); if (likely(written > 0)) iocb->ki_pos += written; } out: current->backing_dev_info = NULL; return written ? written : err; }

Contributors

PersonTokensPropCommitsCommitProp
christoph hellwigchristoph hellwig8932.60%518.52%
jeff moyerjeff moyer6824.91%13.70%
al viroal viro6724.54%414.81%
andrew mortonandrew morton176.23%518.52%
pre-gitpre-git124.40%622.22%
josef bacikjosef bacik93.30%13.70%
matthew wilcoxmatthew wilcox62.20%13.70%
kirill a. shutemovkirill a. shutemov20.73%13.70%
jan karajan kara10.37%13.70%
mika kukkonenmika kukkonen10.37%13.70%
linus torvaldslinus torvalds10.37%13.70%
Total273100.00%27100.00%

EXPORT_SYMBOL(__generic_file_write_iter); /** * generic_file_write_iter - write data to a file * @iocb: IO state structure * @from: iov_iter with data to write * * This is a wrapper around __generic_file_write_iter() to be used by most * filesystems. It takes care of syncing the file in case of O_SYNC file * and acquires i_mutex as needed. */
ssize_t generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file->f_mapping->host; ssize_t ret; inode_lock(inode); ret = generic_write_checks(iocb, from); if (ret > 0) ret = __generic_file_write_iter(iocb, from); inode_unlock(inode); if (ret > 0) ret = generic_write_sync(iocb, ret); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
andrew mortonandrew morton4550.00%323.08%
al viroal viro2224.44%430.77%
benjamin lahaisebenjamin lahaise1617.78%17.69%
jan karajan kara33.33%17.69%
christoph hellwigchristoph hellwig22.22%215.38%
badari pulavartybadari pulavarty11.11%17.69%
rusty russellrusty russell11.11%17.69%
Total90100.00%13100.00%

EXPORT_SYMBOL(generic_file_write_iter); /** * try_to_release_page() - release old fs-specific metadata on a page * * @page: the page which the kernel is trying to free * @gfp_mask: memory allocation flags (and I/O mode) * * The address_space is to try to release any data against the page * (presumably at page->private). If the release was successful, return `1'. * Otherwise return zero. * * This may also be called if PG_fscache is set on a page, indicating that the * page is known to the local caching routines. * * The @gfp_mask argument specifies whether I/O may be performed to release * this page (__GFP_IO), and whether the call may block (__GFP_RECLAIM & __GFP_FS). * */
int try_to_release_page(struct page *page, gfp_t gfp_mask) { struct address_space * const mapping = page->mapping; BUG_ON(!PageLocked(page)); if (PageWriteback(page)) return 0; if (mapping && mapping->a_ops->releasepage) return mapping->a_ops->releasepage(page, gfp_mask); return try_to_free_buffers(page); }

Contributors

PersonTokensPropCommitsCommitProp
david howellsdavid howells70100.00%1100.00%
Total70100.00%1100.00%

EXPORT_SYMBOL(try_to_release_page);

Overall Contributors

PersonTokensPropCommitsCommitProp
nick pigginnick piggin113611.96%307.37%
andrew mortonandrew morton98510.37%6114.99%
johannes weinerjohannes weiner9069.54%112.70%
kirill a. shutemovkirill a. shutemov9049.52%102.46%
linus torvaldslinus torvalds8018.43%235.65%
christoph hellwigchristoph hellwig4714.96%184.42%
pre-gitpre-git4574.81%4811.79%
al viroal viro3053.21%235.65%
mel gormanmel gorman2692.83%92.21%
ross zwislerross zwisler2282.40%40.98%
miklos szeredimiklos szeredi2212.33%40.98%
matthew wilcoxmatthew wilcox1992.10%61.47%
hugh dickinshugh dickins1751.84%92.21%
david howellsdavid howells1681.77%61.47%
jan karajan kara1661.75%122.95%
kosaki motohirokosaki motohiro1331.40%30.74%
wu fengguangwu fengguang1191.25%51.23%
neil brownneil brown1181.24%40.98%
michel lespinassemichel lespinasse1131.19%30.74%
konstantin khlebnikovkonstantin khlebnikov1111.17%20.49%
zach brownzach brown1111.17%20.49%
dmitriy monakhovdmitriy monakhov1051.11%20.49%
sasha levinsasha levin870.92%20.49%
suparna bhattacharyasuparna bhattacharya860.91%30.74%
jun'ichi nomurajun'ichi nomura780.82%10.25%
jeff moyerjeff moyer770.81%30.74%
hisashi hifumihisashi hifumi650.68%30.74%
jens axboejens axboe640.67%40.98%
william lee irwin iiiwilliam lee irwin iii560.59%20.49%
hirofumi ogawahirofumi ogawa530.56%30.74%
michal hockomichal hocko530.56%51.23%
rik van rielrik van riel500.53%40.98%
paul jacksonpaul jackson430.45%10.25%
fengguang wufengguang wu400.42%51.23%
oleg nesterovoleg nesterov340.36%20.49%
arnaldo carvalho de meloarnaldo carvalho de melo320.34%10.25%
dan magenheimerdan magenheimer290.31%20.49%
balbir singhbalbir singh270.28%30.74%
tejun heotejun heo250.26%30.74%
greg thelengreg thelen250.26%10.25%
benjamin lahaisebenjamin lahaise240.25%20.49%
josef bacikjosef bacik220.23%20.49%
marcelo tosattimarcelo tosatti200.21%10.25%
steven prattsteven pratt190.20%10.25%
miao xiemiao xie170.18%10.25%
nicolai stangenicolai stange170.18%10.25%
robert jarzmikrobert jarzmik160.17%10.25%
daisuke nishimuradaisuke nishimura160.17%10.25%
minchan kimminchan kim150.16%30.74%
shaohua lishaohua li150.16%10.25%
rusty russellrusty russell140.15%30.74%
joe perchesjoe perches120.13%10.25%
miquel van smoorenburgmiquel van smoorenburg120.13%20.49%
anfei zhouanfei zhou120.13%10.25%
dave hansendave hansen110.12%10.25%
randy dunlaprandy dunlap100.11%40.98%
darrick j. wongdarrick j. wong100.11%20.49%
evgeniy polyakovevgeniy polyakov100.11%10.25%
ying hanying han90.09%10.25%
christoph lameterchristoph lameter70.07%20.49%
gleb natapovgleb natapov60.06%10.25%
steven whitehousesteven whitehouse60.06%20.49%
roman gushchinroman gushchin60.06%10.25%
kamezawa hiroyukikamezawa hiroyuki60.06%10.25%
chris masonchris mason50.05%10.25%
namhyung kimnamhyung kim50.05%10.25%
nathan scottnathan scott50.05%10.25%
andi kleenandi kleen40.04%10.25%
yan zhengyan zheng40.04%10.25%
hiro yoshiokahiro yoshioka30.03%10.25%
joonsoo kimjoonsoo kim30.03%10.25%
jiri slabyjiri slaby30.03%10.25%
nikita danilovnikita danilov30.03%10.25%
mika kukkonenmika kukkonen30.03%20.49%
stephen d. smalleystephen d. smalley30.03%10.25%
heiko carstensheiko carstens20.02%10.25%
badari pulavartybadari pulavarty20.02%20.49%
arnd bergmannarnd bergmann20.02%10.25%
paul cassellapaul cassella20.02%10.25%
peter zijlstrapeter zijlstra20.02%10.25%
dave kleikampdave kleikamp20.02%10.25%
matt mackallmatt mackall10.01%10.25%
paul gortmakerpaul gortmaker10.01%10.25%
ingo molnaringo molnar10.01%10.25%
daniel mcneildaniel mcneil10.01%10.25%
alexey dobriyanalexey dobriyan10.01%10.25%
michael christiemichael christie10.01%10.25%
masanari iidamasanari iida10.01%10.25%
vlastimil babkavlastimil babka10.01%10.25%
Total9498100.00%407100.00%
Directory: mm
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.