Remove the old fscache I/O API. There's no point trying to transform it as the new one bears no similarities to the old one. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: linux-cachefs@xxxxxxxxxx Link: https://lore.kernel.org/r/158861213535.340223.11422037188513966130.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # fscache rewrite patchset rfc Link: https://lore.kernel.org/r/159465772152.1376105.17485634094767962215.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # fscache rewrite cleanup patch-subset Link: https://lore.kernel.org/r/160588462237.3465195.5911430241577283684.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # fscache modernisation patchset Link: https://lore.kernel.org/r/163162775443.438332.258337773271765659.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # rfc Link: https://lore.kernel.org/r/163189113658.2509237.9999467212589051557.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # rfc v2 --- fs/cachefiles/Makefile | 1 fs/cachefiles/interface.c | 15 - fs/cachefiles/internal.h | 38 - fs/cachefiles/main.c | 1 fs/cachefiles/rdwr.c | 972 ------------------------------------- fs/fscache/cache.c | 6 fs/fscache/cookie.c | 10 fs/fscache/internal.h | 27 - fs/fscache/object.c | 2 fs/fscache/page.c | 1067 ----------------------------------------- fs/fscache/stats.c | 6 fs/nfs/fscache-index.c | 26 - include/linux/fscache-cache.h | 131 ----- include/linux/fscache.h | 358 -------------- 14 files changed, 2 insertions(+), 2658 deletions(-) delete mode 100644 fs/cachefiles/rdwr.c diff --git a/fs/cachefiles/Makefile b/fs/cachefiles/Makefile index 02fd17731769..714e84b3ca24 100644 --- a/fs/cachefiles/Makefile +++ b/fs/cachefiles/Makefile @@ -11,7 +11,6 @@ cachefiles-y := \ key.o \ main.o \ namei.o \ - rdwr.o \ security.o \ xattr.o diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index 8a7755b86c59..83671488a323 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -540,14 +540,6 @@ static void cachefiles_invalidate_object(struct fscache_operation *op) _leave(""); } -/* - * dissociate a cache from all the pages it was backing - */ -static void cachefiles_dissociate_pages(struct fscache_cache *cache) -{ - _enter(""); -} - const struct fscache_cache_ops cachefiles_cache_ops = { .name = "cachefiles", .alloc_object = cachefiles_alloc_object, @@ -560,13 +552,6 @@ const struct fscache_cache_ops cachefiles_cache_ops = { .put_object = cachefiles_put_object, .sync_cache = cachefiles_sync_cache, .attr_changed = cachefiles_attr_changed, - .read_or_alloc_page = cachefiles_read_or_alloc_page, - .read_or_alloc_pages = cachefiles_read_or_alloc_pages, - .allocate_page = cachefiles_allocate_page, - .allocate_pages = cachefiles_allocate_pages, - .write_page = cachefiles_write_page, - .uncache_page = cachefiles_uncache_page, - .dissociate_pages = cachefiles_dissociate_pages, .check_consistency = cachefiles_check_consistency, .begin_operation = cachefiles_begin_operation, }; diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index 994f90ff12ac..de982f4f513f 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -43,7 +43,6 @@ struct cachefiles_object { atomic_t usage; /* object usage count */ uint8_t type; /* object type */ uint8_t new; /* T if object new */ - spinlock_t work_lock; struct rb_node active_node; /* link in active tree (dentry is key) */ }; @@ -89,28 +88,6 @@ struct cachefiles_cache { char *tag; /* cache binding tag */ }; -/* - * backing file read tracking - */ -struct cachefiles_one_read { - wait_queue_entry_t monitor; /* link into monitored waitqueue */ - struct page *back_page; /* backing file page we're waiting for */ - struct page *netfs_page; /* netfs page we're going to fill */ - struct fscache_retrieval *op; /* retrieval op covering this */ - struct list_head op_link; /* link in op's todo list */ -}; - -/* - * backing file write tracking - */ -struct cachefiles_one_write { - struct page *netfs_page; /* netfs page to copy */ - struct cachefiles_object *object; - struct list_head obj_link; /* link in object's lists */ - fscache_rw_complete_t end_io_func; - void *context; -}; - /* * auxiliary data xattr buffer */ @@ -180,21 +157,6 @@ extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, extern int cachefiles_check_in_use(struct cachefiles_cache *cache, struct dentry *dir, char *filename); -/* - * rdwr.c - */ -extern int cachefiles_read_or_alloc_page(struct fscache_retrieval *, - struct page *, gfp_t); -extern int cachefiles_read_or_alloc_pages(struct fscache_retrieval *, - struct list_head *, unsigned *, - gfp_t); -extern int cachefiles_allocate_page(struct fscache_retrieval *, struct page *, - gfp_t); -extern int cachefiles_allocate_pages(struct fscache_retrieval *, - struct list_head *, unsigned *, gfp_t); -extern int cachefiles_write_page(struct fscache_storage *, struct page *); -extern void cachefiles_uncache_page(struct fscache_object *, struct page *); - /* * rdwr2.c */ diff --git a/fs/cachefiles/main.c b/fs/cachefiles/main.c index 9c8d34c49b12..d3115106b22b 100644 --- a/fs/cachefiles/main.c +++ b/fs/cachefiles/main.c @@ -42,7 +42,6 @@ static void cachefiles_object_init_once(void *_object) struct cachefiles_object *object = _object; memset(object, 0, sizeof(*object)); - spin_lock_init(&object->work_lock); } /* diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c deleted file mode 100644 index 8ffc40e84a59..000000000000 --- a/fs/cachefiles/rdwr.c +++ /dev/null @@ -1,972 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* Storage object read/write - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@xxxxxxxxxx) - */ - -#include <linux/mount.h> -#include <linux/slab.h> -#include <linux/file.h> -#include <linux/swap.h> -#include "internal.h" - -/* - * detect wake up events generated by the unlocking of pages in which we're - * interested - * - we use this to detect read completion of backing pages - * - the caller holds the waitqueue lock - */ -static int cachefiles_read_waiter(wait_queue_entry_t *wait, unsigned mode, - int sync, void *_key) -{ - struct cachefiles_one_read *monitor = - container_of(wait, struct cachefiles_one_read, monitor); - struct cachefiles_object *object; - struct fscache_retrieval *op = monitor->op; - struct wait_page_key *key = _key; - struct page *page = wait->private; - - ASSERT(key); - - _enter("{%lu},%u,%d,{%p,%u}", - monitor->netfs_page->index, mode, sync, - key->page, key->bit_nr); - - if (key->page != page || key->bit_nr != PG_locked) - return 0; - - _debug("--- monitor %p %lx ---", page, page->flags); - - if (!PageUptodate(page) && !PageError(page)) { - /* unlocked, not uptodate and not erronous? */ - _debug("page probably truncated"); - } - - /* remove from the waitqueue */ - list_del(&wait->entry); - - /* move onto the action list and queue for FS-Cache thread pool */ - ASSERT(op); - - /* We need to temporarily bump the usage count as we don't own a ref - * here otherwise cachefiles_read_copier() may free the op between the - * monitor being enqueued on the op->to_do list and the op getting - * enqueued on the work queue. - */ - fscache_get_retrieval(op); - - object = container_of(op->op.object, struct cachefiles_object, fscache); - spin_lock(&object->work_lock); - list_add_tail(&monitor->op_link, &op->to_do); - fscache_enqueue_retrieval(op); - spin_unlock(&object->work_lock); - - fscache_put_retrieval(op); - return 0; -} - -/* - * handle a probably truncated page - * - check to see if the page is still relevant and reissue the read if - * possible - * - return -EIO on error, -ENODATA if the page is gone, -EINPROGRESS if we - * must wait again and 0 if successful - */ -static int cachefiles_read_reissue(struct cachefiles_object *object, - struct cachefiles_one_read *monitor) -{ - struct address_space *bmapping = d_backing_inode(object->backer)->i_mapping; - struct page *backpage = monitor->back_page, *backpage2; - int ret; - - _enter("{ino=%lx},{%lx,%lx}", - d_backing_inode(object->backer)->i_ino, - backpage->index, backpage->flags); - - /* skip if the page was truncated away completely */ - if (backpage->mapping != bmapping) { - _leave(" = -ENODATA [mapping]"); - return -ENODATA; - } - - backpage2 = find_get_page(bmapping, backpage->index); - if (!backpage2) { - _leave(" = -ENODATA [gone]"); - return -ENODATA; - } - - if (backpage != backpage2) { - put_page(backpage2); - _leave(" = -ENODATA [different]"); - return -ENODATA; - } - - /* the page is still there and we already have a ref on it, so we don't - * need a second */ - put_page(backpage2); - - INIT_LIST_HEAD(&monitor->op_link); - add_page_wait_queue(backpage, &monitor->monitor); - - if (trylock_page(backpage)) { - ret = -EIO; - if (PageError(backpage)) - goto unlock_discard; - ret = 0; - if (PageUptodate(backpage)) - goto unlock_discard; - - _debug("reissue read"); - ret = bmapping->a_ops->readpage(NULL, backpage); - if (ret < 0) - goto discard; - } - - /* but the page may have been read before the monitor was installed, so - * the monitor may miss the event - so we have to ensure that we do get - * one in such a case */ - if (trylock_page(backpage)) { - _debug("jumpstart %p {%lx}", backpage, backpage->flags); - unlock_page(backpage); - } - - /* it'll reappear on the todo list */ - _leave(" = -EINPROGRESS"); - return -EINPROGRESS; - -unlock_discard: - unlock_page(backpage); -discard: - spin_lock_irq(&object->work_lock); - list_del(&monitor->op_link); - spin_unlock_irq(&object->work_lock); - _leave(" = %d", ret); - return ret; -} - -/* - * copy data from backing pages to netfs pages to complete a read operation - * - driven by FS-Cache's thread pool - */ -static void cachefiles_read_copier(struct fscache_operation *_op) -{ - struct cachefiles_one_read *monitor; - struct cachefiles_object *object; - struct fscache_retrieval *op; - int error, max; - - op = container_of(_op, struct fscache_retrieval, op); - object = container_of(op->op.object, - struct cachefiles_object, fscache); - - _enter("{ino=%lu}", d_backing_inode(object->backer)->i_ino); - - max = 8; - spin_lock_irq(&object->work_lock); - - while (!list_empty(&op->to_do)) { - monitor = list_entry(op->to_do.next, - struct cachefiles_one_read, op_link); - list_del(&monitor->op_link); - - spin_unlock_irq(&object->work_lock); - - _debug("- copy {%lu}", monitor->back_page->index); - - recheck: - if (test_bit(FSCACHE_COOKIE_INVALIDATING, - &object->fscache.cookie->flags)) { - error = -ESTALE; - } else if (PageUptodate(monitor->back_page)) { - copy_highpage(monitor->netfs_page, monitor->back_page); - fscache_mark_page_cached(monitor->op, - monitor->netfs_page); - error = 0; - } else if (!PageError(monitor->back_page)) { - /* the page has probably been truncated */ - error = cachefiles_read_reissue(object, monitor); - if (error == -EINPROGRESS) - goto next; - goto recheck; - } else { - cachefiles_io_error_obj( - object, - "Readpage failed on backing file %lx", - (unsigned long) monitor->back_page->flags); - error = -EIO; - } - - put_page(monitor->back_page); - - fscache_end_io(op, monitor->netfs_page, error); - put_page(monitor->netfs_page); - fscache_retrieval_complete(op, 1); - fscache_put_retrieval(op); - kfree(monitor); - - next: - /* let the thread pool have some air occasionally */ - max--; - if (max < 0 || need_resched()) { - if (!list_empty(&op->to_do)) - fscache_enqueue_retrieval(op); - _leave(" [maxed out]"); - return; - } - - spin_lock_irq(&object->work_lock); - } - - spin_unlock_irq(&object->work_lock); - _leave(""); -} - -/* - * read the corresponding page to the given set from the backing file - * - an uncertain page is simply discarded, to be tried again another time - */ -static int cachefiles_read_backing_file_one(struct cachefiles_object *object, - struct fscache_retrieval *op, - struct page *netpage) -{ - struct cachefiles_one_read *monitor; - struct address_space *bmapping; - struct page *newpage, *backpage; - int ret; - - _enter(""); - - _debug("read back %p{%lu,%d}", - netpage, netpage->index, page_count(netpage)); - - monitor = kzalloc(sizeof(*monitor), cachefiles_gfp); - if (!monitor) - goto nomem; - - monitor->netfs_page = netpage; - monitor->op = fscache_get_retrieval(op); - - init_waitqueue_func_entry(&monitor->monitor, cachefiles_read_waiter); - - /* attempt to get hold of the backing page */ - bmapping = d_backing_inode(object->backer)->i_mapping; - newpage = NULL; - - for (;;) { - backpage = find_get_page(bmapping, netpage->index); - if (backpage) - goto backing_page_already_present; - - if (!newpage) { - newpage = __page_cache_alloc(cachefiles_gfp); - if (!newpage) - goto nomem_monitor; - } - - ret = add_to_page_cache_lru(newpage, bmapping, - netpage->index, cachefiles_gfp); - if (ret == 0) - goto installed_new_backing_page; - if (ret != -EEXIST) - goto nomem_page; - } - - /* we've installed a new backing page, so now we need to start - * it reading */ -installed_new_backing_page: - _debug("- new %p", newpage); - - backpage = newpage; - newpage = NULL; - -read_backing_page: - ret = bmapping->a_ops->readpage(NULL, backpage); - if (ret < 0) - goto read_error; - - /* set the monitor to transfer the data across */ -monitor_backing_page: - _debug("- monitor add"); - - /* install the monitor */ - get_page(monitor->netfs_page); - get_page(backpage); - monitor->back_page = backpage; - monitor->monitor.private = backpage; - add_page_wait_queue(backpage, &monitor->monitor); - monitor = NULL; - - /* but the page may have been read before the monitor was installed, so - * the monitor may miss the event - so we have to ensure that we do get - * one in such a case */ - if (trylock_page(backpage)) { - _debug("jumpstart %p {%lx}", backpage, backpage->flags); - unlock_page(backpage); - } - goto success; - - /* if the backing page is already present, it can be in one of - * three states: read in progress, read failed or read okay */ -backing_page_already_present: - _debug("- present"); - - if (newpage) { - put_page(newpage); - newpage = NULL; - } - - if (PageError(backpage)) - goto io_error; - - if (PageUptodate(backpage)) - goto backing_page_already_uptodate; - - if (!trylock_page(backpage)) - goto monitor_backing_page; - _debug("read %p {%lx}", backpage, backpage->flags); - goto read_backing_page; - - /* the backing page is already up to date, attach the netfs - * page to the pagecache and LRU and copy the data across */ -backing_page_already_uptodate: - _debug("- uptodate"); - - fscache_mark_page_cached(op, netpage); - - copy_highpage(netpage, backpage); - fscache_end_io(op, netpage, 0); - fscache_retrieval_complete(op, 1); - -success: - _debug("success"); - ret = 0; - -out: - if (backpage) - put_page(backpage); - if (monitor) { - fscache_put_retrieval(monitor->op); - kfree(monitor); - } - _leave(" = %d", ret); - return ret; - -read_error: - _debug("read error %d", ret); - if (ret == -ENOMEM) { - fscache_retrieval_complete(op, 1); - goto out; - } -io_error: - cachefiles_io_error_obj(object, "Page read error on backing file"); - fscache_retrieval_complete(op, 1); - ret = -ENOBUFS; - goto out; - -nomem_page: - put_page(newpage); -nomem_monitor: - fscache_put_retrieval(monitor->op); - kfree(monitor); -nomem: - fscache_retrieval_complete(op, 1); - _leave(" = -ENOMEM"); - return -ENOMEM; -} - -/* - * read a page from the cache or allocate a block in which to store it - * - cache withdrawal is prevented by the caller - * - returns -EINTR if interrupted - * - returns -ENOMEM if ran out of memory - * - returns -ENOBUFS if no buffers can be made available - * - returns -ENOBUFS if page is beyond EOF - * - if the page is backed by a block in the cache: - * - a read will be started which will call the callback on completion - * - 0 will be returned - * - else if the page is unbacked: - * - the metadata will be retained - * - -ENODATA will be returned - */ -int cachefiles_read_or_alloc_page(struct fscache_retrieval *op, - struct page *page, - gfp_t gfp) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - struct inode *inode; - sector_t block; - unsigned shift; - int ret, ret2; - - object = container_of(op->op.object, - struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - _enter("{%p},{%lx},,,", object, page->index); - - if (!object->backer) - goto enobufs; - - inode = d_backing_inode(object->backer); - ASSERT(S_ISREG(inode->i_mode)); - - /* calculate the shift required to use bmap */ - shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits; - - op->op.flags &= FSCACHE_OP_KEEP_FLAGS; - op->op.flags |= FSCACHE_OP_ASYNC; - op->op.processor = cachefiles_read_copier; - - /* we assume the absence or presence of the first block is a good - * enough indication for the page as a whole - * - TODO: don't use bmap() for this as it is _not_ actually good - * enough for this as it doesn't indicate errors, but it's all we've - * got for the moment - */ - block = page->index; - block <<= shift; - - ret2 = bmap(inode, &block); - ASSERT(ret2 == 0); - - _debug("%llx -> %llx", - (unsigned long long) (page->index << shift), - (unsigned long long) block); - - if (block) { - /* submit the apparently valid page to the backing fs to be - * read from disk */ - ret = cachefiles_read_backing_file_one(object, op, page); - } else if (cachefiles_has_space(cache, 0, 1) == 0) { - /* there's space in the cache we can use */ - fscache_mark_page_cached(op, page); - fscache_retrieval_complete(op, 1); - ret = -ENODATA; - } else { - goto enobufs; - } - - _leave(" = %d", ret); - return ret; - -enobufs: - fscache_retrieval_complete(op, 1); - _leave(" = -ENOBUFS"); - return -ENOBUFS; -} - -/* - * read the corresponding pages to the given set from the backing file - * - any uncertain pages are simply discarded, to be tried again another time - */ -static int cachefiles_read_backing_file(struct cachefiles_object *object, - struct fscache_retrieval *op, - struct list_head *list) -{ - struct cachefiles_one_read *monitor = NULL; - struct address_space *bmapping = d_backing_inode(object->backer)->i_mapping; - struct page *newpage = NULL, *netpage, *_n, *backpage = NULL; - int ret = 0; - - _enter(""); - - list_for_each_entry_safe(netpage, _n, list, lru) { - list_del(&netpage->lru); - - _debug("read back %p{%lu,%d}", - netpage, netpage->index, page_count(netpage)); - - if (!monitor) { - monitor = kzalloc(sizeof(*monitor), cachefiles_gfp); - if (!monitor) - goto nomem; - - monitor->op = fscache_get_retrieval(op); - init_waitqueue_func_entry(&monitor->monitor, - cachefiles_read_waiter); - } - - for (;;) { - backpage = find_get_page(bmapping, netpage->index); - if (backpage) - goto backing_page_already_present; - - if (!newpage) { - newpage = __page_cache_alloc(cachefiles_gfp); - if (!newpage) - goto nomem; - } - - ret = add_to_page_cache_lru(newpage, bmapping, - netpage->index, - cachefiles_gfp); - if (ret == 0) - goto installed_new_backing_page; - if (ret != -EEXIST) - goto nomem; - } - - /* we've installed a new backing page, so now we need - * to start it reading */ - installed_new_backing_page: - _debug("- new %p", newpage); - - backpage = newpage; - newpage = NULL; - - reread_backing_page: - ret = bmapping->a_ops->readpage(NULL, backpage); - if (ret < 0) - goto read_error; - - /* add the netfs page to the pagecache and LRU, and set the - * monitor to transfer the data across */ - monitor_backing_page: - _debug("- monitor add"); - - ret = add_to_page_cache_lru(netpage, op->mapping, - netpage->index, cachefiles_gfp); - if (ret < 0) { - if (ret == -EEXIST) { - put_page(backpage); - backpage = NULL; - put_page(netpage); - netpage = NULL; - fscache_retrieval_complete(op, 1); - continue; - } - goto nomem; - } - - /* install a monitor */ - get_page(netpage); - monitor->netfs_page = netpage; - - get_page(backpage); - monitor->back_page = backpage; - monitor->monitor.private = backpage; - add_page_wait_queue(backpage, &monitor->monitor); - monitor = NULL; - - /* but the page may have been read before the monitor was - * installed, so the monitor may miss the event - so we have to - * ensure that we do get one in such a case */ - if (trylock_page(backpage)) { - _debug("2unlock %p {%lx}", backpage, backpage->flags); - unlock_page(backpage); - } - - put_page(backpage); - backpage = NULL; - - put_page(netpage); - netpage = NULL; - continue; - - /* if the backing page is already present, it can be in one of - * three states: read in progress, read failed or read okay */ - backing_page_already_present: - _debug("- present %p", backpage); - - if (PageError(backpage)) - goto io_error; - - if (PageUptodate(backpage)) - goto backing_page_already_uptodate; - - _debug("- not ready %p{%lx}", backpage, backpage->flags); - - if (!trylock_page(backpage)) - goto monitor_backing_page; - - if (PageError(backpage)) { - _debug("error %lx", backpage->flags); - unlock_page(backpage); - goto io_error; - } - - if (PageUptodate(backpage)) - goto backing_page_already_uptodate_unlock; - - /* we've locked a page that's neither up to date nor erroneous, - * so we need to attempt to read it again */ - goto reread_backing_page; - - /* the backing page is already up to date, attach the netfs - * page to the pagecache and LRU and copy the data across */ - backing_page_already_uptodate_unlock: - _debug("uptodate %lx", backpage->flags); - unlock_page(backpage); - backing_page_already_uptodate: - _debug("- uptodate"); - - ret = add_to_page_cache_lru(netpage, op->mapping, - netpage->index, cachefiles_gfp); - if (ret < 0) { - if (ret == -EEXIST) { - put_page(backpage); - backpage = NULL; - put_page(netpage); - netpage = NULL; - fscache_retrieval_complete(op, 1); - continue; - } - goto nomem; - } - - copy_highpage(netpage, backpage); - - put_page(backpage); - backpage = NULL; - - fscache_mark_page_cached(op, netpage); - - /* the netpage is unlocked and marked up to date here */ - fscache_end_io(op, netpage, 0); - put_page(netpage); - netpage = NULL; - fscache_retrieval_complete(op, 1); - continue; - } - - netpage = NULL; - - _debug("out"); - -out: - /* tidy up */ - if (newpage) - put_page(newpage); - if (netpage) - put_page(netpage); - if (backpage) - put_page(backpage); - if (monitor) { - fscache_put_retrieval(op); - kfree(monitor); - } - - list_for_each_entry_safe(netpage, _n, list, lru) { - list_del(&netpage->lru); - put_page(netpage); - fscache_retrieval_complete(op, 1); - } - - _leave(" = %d", ret); - return ret; - -nomem: - _debug("nomem"); - ret = -ENOMEM; - goto record_page_complete; - -read_error: - _debug("read error %d", ret); - if (ret == -ENOMEM) - goto record_page_complete; -io_error: - cachefiles_io_error_obj(object, "Page read error on backing file"); - ret = -ENOBUFS; -record_page_complete: - fscache_retrieval_complete(op, 1); - goto out; -} - -/* - * read a list of pages from the cache or allocate blocks in which to store - * them - */ -int cachefiles_read_or_alloc_pages(struct fscache_retrieval *op, - struct list_head *pages, - unsigned *nr_pages, - gfp_t gfp) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - struct list_head backpages; - struct pagevec pagevec; - struct inode *inode; - struct page *page, *_n; - unsigned shift, nrbackpages; - int ret, ret2, space; - - object = container_of(op->op.object, - struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - _enter("{OBJ%x,%d},,%d,,", - object->fscache.debug_id, atomic_read(&op->op.usage), - *nr_pages); - - if (!object->backer) - goto all_enobufs; - - space = 1; - if (cachefiles_has_space(cache, 0, *nr_pages) < 0) - space = 0; - - inode = d_backing_inode(object->backer); - ASSERT(S_ISREG(inode->i_mode)); - - /* calculate the shift required to use bmap */ - shift = PAGE_SHIFT - inode->i_sb->s_blocksize_bits; - - pagevec_init(&pagevec); - - op->op.flags &= FSCACHE_OP_KEEP_FLAGS; - op->op.flags |= FSCACHE_OP_ASYNC; - op->op.processor = cachefiles_read_copier; - - INIT_LIST_HEAD(&backpages); - nrbackpages = 0; - - ret = space ? -ENODATA : -ENOBUFS; - list_for_each_entry_safe(page, _n, pages, lru) { - sector_t block; - - /* we assume the absence or presence of the first block is a - * good enough indication for the page as a whole - * - TODO: don't use bmap() for this as it is _not_ actually - * good enough for this as it doesn't indicate errors, but - * it's all we've got for the moment - */ - block = page->index; - block <<= shift; - - ret2 = bmap(inode, &block); - ASSERT(ret2 == 0); - - _debug("%llx -> %llx", - (unsigned long long) (page->index << shift), - (unsigned long long) block); - - if (block) { - /* we have data - add it to the list to give to the - * backing fs */ - list_move(&page->lru, &backpages); - (*nr_pages)--; - nrbackpages++; - } else if (space && pagevec_add(&pagevec, page) == 0) { - fscache_mark_pages_cached(op, &pagevec); - fscache_retrieval_complete(op, 1); - ret = -ENODATA; - } else { - fscache_retrieval_complete(op, 1); - } - } - - if (pagevec_count(&pagevec) > 0) - fscache_mark_pages_cached(op, &pagevec); - - if (list_empty(pages)) - ret = 0; - - /* submit the apparently valid pages to the backing fs to be read from - * disk */ - if (nrbackpages > 0) { - ret2 = cachefiles_read_backing_file(object, op, &backpages); - if (ret2 == -ENOMEM || ret2 == -EINTR) - ret = ret2; - } - - _leave(" = %d [nr=%u%s]", - ret, *nr_pages, list_empty(pages) ? " empty" : ""); - return ret; - -all_enobufs: - fscache_retrieval_complete(op, *nr_pages); - return -ENOBUFS; -} - -/* - * allocate a block in the cache in which to store a page - * - cache withdrawal is prevented by the caller - * - returns -EINTR if interrupted - * - returns -ENOMEM if ran out of memory - * - returns -ENOBUFS if no buffers can be made available - * - returns -ENOBUFS if page is beyond EOF - * - otherwise: - * - the metadata will be retained - * - 0 will be returned - */ -int cachefiles_allocate_page(struct fscache_retrieval *op, - struct page *page, - gfp_t gfp) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - int ret; - - object = container_of(op->op.object, - struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - _enter("%p,{%lx},", object, page->index); - - ret = cachefiles_has_space(cache, 0, 1); - if (ret == 0) - fscache_mark_page_cached(op, page); - else - ret = -ENOBUFS; - - fscache_retrieval_complete(op, 1); - _leave(" = %d", ret); - return ret; -} - -/* - * allocate blocks in the cache in which to store a set of pages - * - cache withdrawal is prevented by the caller - * - returns -EINTR if interrupted - * - returns -ENOMEM if ran out of memory - * - returns -ENOBUFS if some buffers couldn't be made available - * - returns -ENOBUFS if some pages are beyond EOF - * - otherwise: - * - -ENODATA will be returned - * - metadata will be retained for any page marked - */ -int cachefiles_allocate_pages(struct fscache_retrieval *op, - struct list_head *pages, - unsigned *nr_pages, - gfp_t gfp) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - struct pagevec pagevec; - struct page *page; - int ret; - - object = container_of(op->op.object, - struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - _enter("%p,,,%d,", object, *nr_pages); - - ret = cachefiles_has_space(cache, 0, *nr_pages); - if (ret == 0) { - pagevec_init(&pagevec); - - list_for_each_entry(page, pages, lru) { - if (pagevec_add(&pagevec, page) == 0) - fscache_mark_pages_cached(op, &pagevec); - } - - if (pagevec_count(&pagevec) > 0) - fscache_mark_pages_cached(op, &pagevec); - ret = -ENODATA; - } else { - ret = -ENOBUFS; - } - - fscache_retrieval_complete(op, *nr_pages); - _leave(" = %d", ret); - return ret; -} - -/* - * request a page be stored in the cache - * - cache withdrawal is prevented by the caller - * - this request may be ignored if there's no cache block available, in which - * case -ENOBUFS will be returned - * - if the op is in progress, 0 will be returned - */ -int cachefiles_write_page(struct fscache_storage *op, struct page *page) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - struct file *file; - struct path path; - loff_t pos, eof; - size_t len; - void *data; - int ret = -ENOBUFS; - - ASSERT(op != NULL); - ASSERT(page != NULL); - - object = container_of(op->op.object, - struct cachefiles_object, fscache); - - _enter("%p,%p{%lx},,,", object, page, page->index); - - if (!object->backer) { - _leave(" = -ENOBUFS"); - return -ENOBUFS; - } - - ASSERT(d_is_reg(object->backer)); - - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - pos = (loff_t)page->index << PAGE_SHIFT; - - /* We mustn't write more data than we have, so we have to beware of a - * partial page at EOF. - */ - eof = object->fscache.store_limit_l; - if (pos >= eof) - goto error; - - /* write the page to the backing filesystem and let it store it in its - * own time */ - path.mnt = cache->mnt; - path.dentry = object->backer; - file = dentry_open(&path, O_RDWR | O_LARGEFILE, cache->cache_cred); - if (IS_ERR(file)) { - ret = PTR_ERR(file); - goto error_2; - } - - len = PAGE_SIZE; - if (eof & ~PAGE_MASK) { - if (eof - pos < PAGE_SIZE) { - _debug("cut short %llx to %llx", - pos, eof); - len = eof - pos; - ASSERTCMP(pos + len, ==, eof); - } - } - - data = kmap(page); - ret = kernel_write(file, data, len, &pos); - kunmap(page); - fput(file); - if (ret != len) - goto error_eio; - - _leave(" = 0"); - return 0; - -error_eio: - ret = -EIO; -error_2: - if (ret == -EIO) - cachefiles_io_error_obj(object, - "Write page to backing file failed"); -error: - _leave(" = -ENOBUFS [%d]", ret); - return -ENOBUFS; -} - -/* - * detach a backing block from a page - * - cache withdrawal is prevented by the caller - */ -void cachefiles_uncache_page(struct fscache_object *_object, struct page *page) - __releases(&object->fscache.cookie->lock) -{ - struct cachefiles_object *object; - - object = container_of(_object, struct cachefiles_object, fscache); - - _enter("%p,{%lu}", object, page->index); - - spin_unlock(&object->fscache.cookie->lock); -} diff --git a/fs/fscache/cache.c b/fs/fscache/cache.c index bd4f44c1cce0..cfa60c2faf68 100644 --- a/fs/fscache/cache.c +++ b/fs/fscache/cache.c @@ -381,12 +381,6 @@ void fscache_withdraw_cache(struct fscache_cache *cache) cache->ops->sync_cache(cache); fscache_stat_d(&fscache_n_cop_sync_cache); - /* dissociate all the netfs pages backed by this cache from the block - * mappings in the cache */ - fscache_stat(&fscache_n_cop_dissociate_pages); - cache->ops->dissociate_pages(cache); - fscache_stat_d(&fscache_n_cop_dissociate_pages); - /* we now have to destroy all the active objects pertaining to this * cache - which we do by passing them off to thread pool to be * disposed of */ diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index cd42be646ed3..8a850c3d0775 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -179,13 +179,8 @@ struct fscache_cookie *fscache_alloc_cookie( cookie->flags = (1 << FSCACHE_COOKIE_NO_DATA_YET); cookie->type = def->type; spin_lock_init(&cookie->lock); - spin_lock_init(&cookie->stores_lock); INIT_HLIST_HEAD(&cookie->backing_objects); - /* radix tree insertion won't use the preallocation pool unless it's - * told it may not wait */ - INIT_RADIX_TREE(&cookie->stores, GFP_NOFS & ~__GFP_DIRECT_RECLAIM); - write_lock(&fscache_cookies_lock); list_add_tail(&cookie->proc_link, &fscache_cookies); write_unlock(&fscache_cookies_lock); @@ -771,10 +766,6 @@ void __fscache_disable_cookie(struct fscache_cookie *cookie, !atomic_read(&cookie->n_active)); } - /* Make sure any pending writes are cancelled. */ - if (cookie->type != FSCACHE_COOKIE_TYPE_INDEX) - fscache_invalidate_writes(cookie); - /* Reset the cookie state if it wasn't relinquished */ if (!test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags)) { atomic_inc(&cookie->n_active); @@ -823,7 +814,6 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, /* Clear pointers back to the netfs */ cookie->netfs_data = NULL; cookie->def = NULL; - BUG_ON(!radix_tree_empty(&cookie->stores)); if (cookie->parent) { ASSERTCMP(refcount_read(&cookie->parent->ref), >, 0); diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h index 1d1046408311..5281fa1894cd 100644 --- a/fs/fscache/internal.h +++ b/fs/fscache/internal.h @@ -116,11 +116,6 @@ extern int fscache_wait_for_operation_activation(struct fscache_object *, struct fscache_operation *, atomic_t *, atomic_t *); -extern void fscache_invalidate_writes(struct fscache_cookie *); -struct fscache_retrieval *fscache_alloc_retrieval(struct fscache_cookie *cookie, - struct address_space *mapping, - fscache_rw_complete_t end_io_func, - void *context); /* * proc.c @@ -253,7 +248,6 @@ extern atomic_t fscache_n_cop_allocate_page; extern atomic_t fscache_n_cop_allocate_pages; extern atomic_t fscache_n_cop_write_page; extern atomic_t fscache_n_cop_uncache_page; -extern atomic_t fscache_n_cop_dissociate_pages; extern atomic_t fscache_n_cache_no_space_reject; extern atomic_t fscache_n_cache_stale_objects; @@ -298,27 +292,6 @@ static inline void fscache_raise_event(struct fscache_object *object, fscache_enqueue_object(object); } -/* - * get an extra reference to a netfs retrieval context - */ -static inline -void *fscache_get_context(struct fscache_cookie *cookie, void *context) -{ - if (cookie->def->get_context) - cookie->def->get_context(cookie->netfs_data, context); - return context; -} - -/* - * release a reference to a netfs retrieval context - */ -static inline -void fscache_put_context(struct fscache_cookie *cookie, void *context) -{ - if (cookie->def->put_context) - cookie->def->put_context(cookie->netfs_data, context); -} - /* * Update the auxiliary data on a cookie. */ diff --git a/fs/fscache/object.c b/fs/fscache/object.c index 6a675652129b..86ad941726f7 100644 --- a/fs/fscache/object.c +++ b/fs/fscache/object.c @@ -965,14 +965,12 @@ static const struct fscache_state *_fscache_invalidate_object(struct fscache_obj * retire the object instead. */ if (!fscache_use_cookie(object)) { - ASSERT(radix_tree_empty(&object->cookie->stores)); set_bit(FSCACHE_OBJECT_RETIRED, &object->flags); _leave(" [no cookie]"); return transit_to(KILL_OBJECT); } /* Reject any new read/write ops and abort any that are pending. */ - fscache_invalidate_writes(cookie); clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); fscache_cancel_all_ops(object); diff --git a/fs/fscache/page.c b/fs/fscache/page.c index ed41a00b861c..3fd6a2b45fed 100644 --- a/fs/fscache/page.c +++ b/fs/fscache/page.c @@ -7,181 +7,12 @@ #define FSCACHE_DEBUG_LEVEL PAGE #include <linux/module.h> -#define FSCACHE_USE_OLD_IO_API #include <linux/fscache-cache.h> #include <linux/buffer_head.h> #include <linux/pagevec.h> #include <linux/slab.h> #include "internal.h" -/* - * check to see if a page is being written to the cache - */ -bool __fscache_check_page_write(struct fscache_cookie *cookie, struct page *page) -{ - void *val; - - rcu_read_lock(); - val = radix_tree_lookup(&cookie->stores, page->index); - rcu_read_unlock(); - trace_fscache_check_page(cookie, page, val, 0); - - return val != NULL; -} -EXPORT_SYMBOL(__fscache_check_page_write); - -/* - * wait for a page to finish being written to the cache - */ -void __fscache_wait_on_page_write(struct fscache_cookie *cookie, struct page *page) -{ - wait_queue_head_t *wq = bit_waitqueue(&cookie->flags, 0); - - trace_fscache_page(cookie, page, fscache_page_write_wait); - - wait_event(*wq, !__fscache_check_page_write(cookie, page)); -} -EXPORT_SYMBOL(__fscache_wait_on_page_write); - -/* - * wait for a page to finish being written to the cache. Put a timeout here - * since we might be called recursively via parent fs. - */ -static -bool release_page_wait_timeout(struct fscache_cookie *cookie, struct page *page) -{ - wait_queue_head_t *wq = bit_waitqueue(&cookie->flags, 0); - - return wait_event_timeout(*wq, !__fscache_check_page_write(cookie, page), - HZ); -} - -/* - * decide whether a page can be released, possibly by cancelling a store to it - * - we're allowed to sleep if __GFP_DIRECT_RECLAIM is flagged - */ -bool __fscache_maybe_release_page(struct fscache_cookie *cookie, - struct page *page, - gfp_t gfp) -{ - struct page *xpage; - void *val; - - _enter("%p,%p,%x", cookie, page, gfp); - - trace_fscache_page(cookie, page, fscache_page_maybe_release); - -try_again: - rcu_read_lock(); - val = radix_tree_lookup(&cookie->stores, page->index); - if (!val) { - rcu_read_unlock(); - fscache_stat(&fscache_n_store_vmscan_not_storing); - __fscache_uncache_page(cookie, page); - return true; - } - - /* see if the page is actually undergoing storage - if so we can't get - * rid of it till the cache has finished with it */ - if (radix_tree_tag_get(&cookie->stores, page->index, - FSCACHE_COOKIE_STORING_TAG)) { - rcu_read_unlock(); - goto page_busy; - } - - /* the page is pending storage, so we attempt to cancel the store and - * discard the store request so that the page can be reclaimed */ - spin_lock(&cookie->stores_lock); - rcu_read_unlock(); - - if (radix_tree_tag_get(&cookie->stores, page->index, - FSCACHE_COOKIE_STORING_TAG)) { - /* the page started to undergo storage whilst we were looking, - * so now we can only wait or return */ - spin_unlock(&cookie->stores_lock); - goto page_busy; - } - - xpage = radix_tree_delete(&cookie->stores, page->index); - trace_fscache_page(cookie, page, fscache_page_radix_delete); - spin_unlock(&cookie->stores_lock); - - if (xpage) { - fscache_stat(&fscache_n_store_vmscan_cancelled); - fscache_stat(&fscache_n_store_radix_deletes); - ASSERTCMP(xpage, ==, page); - } else { - fscache_stat(&fscache_n_store_vmscan_gone); - } - - wake_up_bit(&cookie->flags, 0); - trace_fscache_wake_cookie(cookie); - if (xpage) - put_page(xpage); - __fscache_uncache_page(cookie, page); - return true; - -page_busy: - /* We will wait here if we're allowed to, but that could deadlock the - * allocator as the work threads writing to the cache may all end up - * sleeping on memory allocation, so we may need to impose a timeout - * too. */ - if (!(gfp & __GFP_DIRECT_RECLAIM) || !(gfp & __GFP_FS)) { - fscache_stat(&fscache_n_store_vmscan_busy); - return false; - } - - fscache_stat(&fscache_n_store_vmscan_wait); - if (!release_page_wait_timeout(cookie, page)) - _debug("fscache writeout timeout page: %p{%lx}", - page, page->index); - - gfp &= ~__GFP_DIRECT_RECLAIM; - goto try_again; -} -EXPORT_SYMBOL(__fscache_maybe_release_page); - -/* - * note that a page has finished being written to the cache - */ -static void fscache_end_page_write(struct fscache_object *object, - struct page *page) -{ - struct fscache_cookie *cookie; - struct page *xpage = NULL, *val; - - spin_lock(&object->lock); - cookie = object->cookie; - if (cookie) { - /* delete the page from the tree if it is now no longer - * pending */ - spin_lock(&cookie->stores_lock); - radix_tree_tag_clear(&cookie->stores, page->index, - FSCACHE_COOKIE_STORING_TAG); - trace_fscache_page(cookie, page, fscache_page_radix_clear_store); - if (!radix_tree_tag_get(&cookie->stores, page->index, - FSCACHE_COOKIE_PENDING_TAG)) { - fscache_stat(&fscache_n_store_radix_deletes); - xpage = radix_tree_delete(&cookie->stores, page->index); - trace_fscache_page(cookie, page, fscache_page_radix_delete); - trace_fscache_page(cookie, page, fscache_page_write_end); - - val = radix_tree_lookup(&cookie->stores, page->index); - trace_fscache_check_page(cookie, page, val, 1); - } else { - trace_fscache_page(cookie, page, fscache_page_write_end_pend); - } - spin_unlock(&cookie->stores_lock); - wake_up_bit(&cookie->flags, 0); - trace_fscache_wake_cookie(cookie); - } else { - trace_fscache_page(cookie, page, fscache_page_write_end_noc); - } - spin_unlock(&object->lock); - if (xpage) - put_page(xpage); -} - /* * actually apply the changed attributes to a cache object */ @@ -266,74 +97,6 @@ int __fscache_attr_changed(struct fscache_cookie *cookie) } EXPORT_SYMBOL(__fscache_attr_changed); -/* - * Handle cancellation of a pending retrieval op - */ -static void fscache_do_cancel_retrieval(struct fscache_operation *_op) -{ - struct fscache_retrieval *op = - container_of(_op, struct fscache_retrieval, op); - - atomic_set(&op->n_pages, 0); -} - -/* - * release a retrieval op reference - */ -static void fscache_release_retrieval_op(struct fscache_operation *_op) -{ - struct fscache_retrieval *op = - container_of(_op, struct fscache_retrieval, op); - - _enter("{OP%x}", op->op.debug_id); - - ASSERTIFCMP(op->op.state != FSCACHE_OP_ST_INITIALISED, - atomic_read(&op->n_pages), ==, 0); - - if (op->context) - fscache_put_context(op->cookie, op->context); - - _leave(""); -} - -/* - * allocate a retrieval op - */ -struct fscache_retrieval *fscache_alloc_retrieval( - struct fscache_cookie *cookie, - struct address_space *mapping, - fscache_rw_complete_t end_io_func, - void *context) -{ - struct fscache_retrieval *op; - - /* allocate a retrieval operation and attempt to submit it */ - op = kzalloc(sizeof(*op), GFP_NOIO); - if (!op) { - fscache_stat(&fscache_n_retrievals_nomem); - return NULL; - } - - fscache_operation_init(cookie, &op->op, NULL, - fscache_do_cancel_retrieval, - fscache_release_retrieval_op); - op->op.flags = FSCACHE_OP_MYTHREAD | - (1UL << FSCACHE_OP_WAITING) | - (1UL << FSCACHE_OP_UNUSE_COOKIE); - op->cookie = cookie; - op->mapping = mapping; - op->end_io_func = end_io_func; - op->context = context; - INIT_LIST_HEAD(&op->to_do); - - /* Pin the netfs read context in case we need to do the actual netfs - * read because we've encountered a cache read failure. - */ - if (context) - fscache_get_context(op->cookie, context); - return op; -} - /* * wait for a deferred lookup to complete */ @@ -411,833 +174,3 @@ int fscache_wait_for_operation_activation(struct fscache_object *object, } return 0; } - -/* - * read a page from the cache or allocate a block in which to store it - * - we return: - * -ENOMEM - out of memory, nothing done - * -ERESTARTSYS - interrupted - * -ENOBUFS - no backing object available in which to cache the block - * -ENODATA - no data available in the backing object for this block - * 0 - dispatched a read - it'll call end_io_func() when finished - */ -int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, - struct page *page, - fscache_rw_complete_t end_io_func, - void *context, - gfp_t gfp) -{ - struct fscache_retrieval *op; - struct fscache_object *object; - bool wake_cookie = false; - int ret; - - _enter("%p,%p,,,", cookie, page); - - fscache_stat(&fscache_n_retrievals); - - if (hlist_empty(&cookie->backing_objects)) - goto nobufs; - - if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { - _leave(" = -ENOBUFS [invalidating]"); - return -ENOBUFS; - } - - ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); - ASSERTCMP(page, !=, NULL); - - if (fscache_wait_for_deferred_lookup(cookie) < 0) - return -ERESTARTSYS; - - op = fscache_alloc_retrieval(cookie, page->mapping, - end_io_func, context); - if (!op) { - _leave(" = -ENOMEM"); - return -ENOMEM; - } - atomic_set(&op->n_pages, 1); - trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_retr_one); - - spin_lock(&cookie->lock); - - if (!fscache_cookie_enabled(cookie) || - hlist_empty(&cookie->backing_objects)) - goto nobufs_unlock; - object = hlist_entry(cookie->backing_objects.first, - struct fscache_object, cookie_link); - - ASSERT(test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags)); - - __fscache_use_cookie(cookie); - atomic_inc(&object->n_reads); - __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); - - if (fscache_submit_op(object, &op->op) < 0) - goto nobufs_unlock_dec; - spin_unlock(&cookie->lock); - - fscache_stat(&fscache_n_retrieval_ops); - - /* we wait for the operation to become active, and then process it - * *here*, in this thread, and not in the thread pool */ - ret = fscache_wait_for_operation_activation( - object, &op->op, - __fscache_stat(&fscache_n_retrieval_op_waits), - __fscache_stat(&fscache_n_retrievals_object_dead)); - if (ret < 0) - goto error; - - /* ask the cache to honour the operation */ - if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) { - fscache_stat(&fscache_n_cop_allocate_page); - ret = object->cache->ops->allocate_page(op, page, gfp); - fscache_stat_d(&fscache_n_cop_allocate_page); - if (ret == 0) - ret = -ENODATA; - } else { - fscache_stat(&fscache_n_cop_read_or_alloc_page); - ret = object->cache->ops->read_or_alloc_page(op, page, gfp); - fscache_stat_d(&fscache_n_cop_read_or_alloc_page); - } - -error: - if (ret == -ENOMEM) - fscache_stat(&fscache_n_retrievals_nomem); - else if (ret == -ERESTARTSYS) - fscache_stat(&fscache_n_retrievals_intr); - else if (ret == -ENODATA) - fscache_stat(&fscache_n_retrievals_nodata); - else if (ret < 0) - fscache_stat(&fscache_n_retrievals_nobufs); - else - fscache_stat(&fscache_n_retrievals_ok); - - fscache_put_retrieval(op); - _leave(" = %d", ret); - return ret; - -nobufs_unlock_dec: - atomic_dec(&object->n_reads); - wake_cookie = __fscache_unuse_cookie(cookie); -nobufs_unlock: - spin_unlock(&cookie->lock); - if (wake_cookie) - __fscache_wake_unused_cookie(cookie); - fscache_put_retrieval(op); -nobufs: - fscache_stat(&fscache_n_retrievals_nobufs); - _leave(" = -ENOBUFS"); - return -ENOBUFS; -} -EXPORT_SYMBOL(__fscache_read_or_alloc_page); - -/* - * read a list of page from the cache or allocate a block in which to store - * them - * - we return: - * -ENOMEM - out of memory, some pages may be being read - * -ERESTARTSYS - interrupted, some pages may be being read - * -ENOBUFS - no backing object or space available in which to cache any - * pages not being read - * -ENODATA - no data available in the backing object for some or all of - * the pages - * 0 - dispatched a read on all pages - * - * end_io_func() will be called for each page read from the cache as it is - * finishes being read - * - * any pages for which a read is dispatched will be removed from pages and - * nr_pages - */ -int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, - struct address_space *mapping, - struct list_head *pages, - unsigned *nr_pages, - fscache_rw_complete_t end_io_func, - void *context, - gfp_t gfp) -{ - struct fscache_retrieval *op; - struct fscache_object *object; - bool wake_cookie = false; - int ret; - - _enter("%p,,%d,,,", cookie, *nr_pages); - - fscache_stat(&fscache_n_retrievals); - - if (hlist_empty(&cookie->backing_objects)) - goto nobufs; - - if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { - _leave(" = -ENOBUFS [invalidating]"); - return -ENOBUFS; - } - - ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); - ASSERTCMP(*nr_pages, >, 0); - ASSERT(!list_empty(pages)); - - if (fscache_wait_for_deferred_lookup(cookie) < 0) - return -ERESTARTSYS; - - op = fscache_alloc_retrieval(cookie, mapping, end_io_func, context); - if (!op) - return -ENOMEM; - atomic_set(&op->n_pages, *nr_pages); - trace_fscache_page_op(cookie, NULL, &op->op, fscache_page_op_retr_multi); - - spin_lock(&cookie->lock); - - if (!fscache_cookie_enabled(cookie) || - hlist_empty(&cookie->backing_objects)) - goto nobufs_unlock; - object = hlist_entry(cookie->backing_objects.first, - struct fscache_object, cookie_link); - - __fscache_use_cookie(cookie); - atomic_inc(&object->n_reads); - __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); - - if (fscache_submit_op(object, &op->op) < 0) - goto nobufs_unlock_dec; - spin_unlock(&cookie->lock); - - fscache_stat(&fscache_n_retrieval_ops); - - /* we wait for the operation to become active, and then process it - * *here*, in this thread, and not in the thread pool */ - ret = fscache_wait_for_operation_activation( - object, &op->op, - __fscache_stat(&fscache_n_retrieval_op_waits), - __fscache_stat(&fscache_n_retrievals_object_dead)); - if (ret < 0) - goto error; - - /* ask the cache to honour the operation */ - if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) { - fscache_stat(&fscache_n_cop_allocate_pages); - ret = object->cache->ops->allocate_pages( - op, pages, nr_pages, gfp); - fscache_stat_d(&fscache_n_cop_allocate_pages); - } else { - fscache_stat(&fscache_n_cop_read_or_alloc_pages); - ret = object->cache->ops->read_or_alloc_pages( - op, pages, nr_pages, gfp); - fscache_stat_d(&fscache_n_cop_read_or_alloc_pages); - } - -error: - if (ret == -ENOMEM) - fscache_stat(&fscache_n_retrievals_nomem); - else if (ret == -ERESTARTSYS) - fscache_stat(&fscache_n_retrievals_intr); - else if (ret == -ENODATA) - fscache_stat(&fscache_n_retrievals_nodata); - else if (ret < 0) - fscache_stat(&fscache_n_retrievals_nobufs); - else - fscache_stat(&fscache_n_retrievals_ok); - - fscache_put_retrieval(op); - _leave(" = %d", ret); - return ret; - -nobufs_unlock_dec: - atomic_dec(&object->n_reads); - wake_cookie = __fscache_unuse_cookie(cookie); -nobufs_unlock: - spin_unlock(&cookie->lock); - fscache_put_retrieval(op); - if (wake_cookie) - __fscache_wake_unused_cookie(cookie); -nobufs: - fscache_stat(&fscache_n_retrievals_nobufs); - _leave(" = -ENOBUFS"); - return -ENOBUFS; -} -EXPORT_SYMBOL(__fscache_read_or_alloc_pages); - -/* - * allocate a block in the cache on which to store a page - * - we return: - * -ENOMEM - out of memory, nothing done - * -ERESTARTSYS - interrupted - * -ENOBUFS - no backing object available in which to cache the block - * 0 - block allocated - */ -int __fscache_alloc_page(struct fscache_cookie *cookie, - struct page *page, - gfp_t gfp) -{ - struct fscache_retrieval *op; - struct fscache_object *object; - bool wake_cookie = false; - int ret; - - _enter("%p,%p,,,", cookie, page); - - fscache_stat(&fscache_n_allocs); - - if (hlist_empty(&cookie->backing_objects)) - goto nobufs; - - ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); - ASSERTCMP(page, !=, NULL); - - if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { - _leave(" = -ENOBUFS [invalidating]"); - return -ENOBUFS; - } - - if (fscache_wait_for_deferred_lookup(cookie) < 0) - return -ERESTARTSYS; - - op = fscache_alloc_retrieval(cookie, page->mapping, NULL, NULL); - if (!op) - return -ENOMEM; - atomic_set(&op->n_pages, 1); - trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_alloc_one); - - spin_lock(&cookie->lock); - - if (!fscache_cookie_enabled(cookie) || - hlist_empty(&cookie->backing_objects)) - goto nobufs_unlock; - object = hlist_entry(cookie->backing_objects.first, - struct fscache_object, cookie_link); - - __fscache_use_cookie(cookie); - if (fscache_submit_op(object, &op->op) < 0) - goto nobufs_unlock_dec; - spin_unlock(&cookie->lock); - - fscache_stat(&fscache_n_alloc_ops); - - ret = fscache_wait_for_operation_activation( - object, &op->op, - __fscache_stat(&fscache_n_alloc_op_waits), - __fscache_stat(&fscache_n_allocs_object_dead)); - if (ret < 0) - goto error; - - /* ask the cache to honour the operation */ - fscache_stat(&fscache_n_cop_allocate_page); - ret = object->cache->ops->allocate_page(op, page, gfp); - fscache_stat_d(&fscache_n_cop_allocate_page); - -error: - if (ret == -ERESTARTSYS) - fscache_stat(&fscache_n_allocs_intr); - else if (ret < 0) - fscache_stat(&fscache_n_allocs_nobufs); - else - fscache_stat(&fscache_n_allocs_ok); - - fscache_put_retrieval(op); - _leave(" = %d", ret); - return ret; - -nobufs_unlock_dec: - wake_cookie = __fscache_unuse_cookie(cookie); -nobufs_unlock: - spin_unlock(&cookie->lock); - fscache_put_retrieval(op); - if (wake_cookie) - __fscache_wake_unused_cookie(cookie); -nobufs: - fscache_stat(&fscache_n_allocs_nobufs); - _leave(" = -ENOBUFS"); - return -ENOBUFS; -} -EXPORT_SYMBOL(__fscache_alloc_page); - -/* - * Unmark pages allocate in the readahead code path (via: - * fscache_readpages_or_alloc) after delegating to the base filesystem - */ -void __fscache_readpages_cancel(struct fscache_cookie *cookie, - struct list_head *pages) -{ - struct page *page; - - list_for_each_entry(page, pages, lru) { - if (PageFsCache(page)) - __fscache_uncache_page(cookie, page); - } -} -EXPORT_SYMBOL(__fscache_readpages_cancel); - -/* - * release a write op reference - */ -static void fscache_release_write_op(struct fscache_operation *_op) -{ - _enter("{OP%x}", _op->debug_id); -} - -/* - * perform the background storage of a page into the cache - */ -static void fscache_write_op(struct fscache_operation *_op) -{ - struct fscache_storage *op = - container_of(_op, struct fscache_storage, op); - struct fscache_object *object = op->op.object; - struct fscache_cookie *cookie; - struct page *page; - unsigned n; - void *results[1]; - int ret; - - _enter("{OP%x,%d}", op->op.debug_id, atomic_read(&op->op.usage)); - -again: - spin_lock(&object->lock); - cookie = object->cookie; - - if (!fscache_object_is_active(object)) { - /* If we get here, then the on-disk cache object likely no - * longer exists, so we should just cancel this write - * operation. - */ - spin_unlock(&object->lock); - fscache_op_complete(&op->op, true); - _leave(" [inactive]"); - return; - } - - if (!cookie) { - /* If we get here, then the cookie belonging to the object was - * detached, probably by the cookie being withdrawn due to - * memory pressure, which means that the pages we might write - * to the cache from no longer exist - therefore, we can just - * cancel this write operation. - */ - spin_unlock(&object->lock); - fscache_op_complete(&op->op, true); - _leave(" [cancel] op{f=%lx s=%u} obj{s=%s f=%lx}", - _op->flags, _op->state, object->state->short_name, - object->flags); - return; - } - - spin_lock(&cookie->stores_lock); - - fscache_stat(&fscache_n_store_calls); - - /* find a page to store */ - results[0] = NULL; - page = NULL; - n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, 1, - FSCACHE_COOKIE_PENDING_TAG); - trace_fscache_gang_lookup(cookie, &op->op, results, n, op->store_limit); - if (n != 1) - goto superseded; - page = results[0]; - _debug("gang %d [%lx]", n, page->index); - - radix_tree_tag_set(&cookie->stores, page->index, - FSCACHE_COOKIE_STORING_TAG); - radix_tree_tag_clear(&cookie->stores, page->index, - FSCACHE_COOKIE_PENDING_TAG); - trace_fscache_page(cookie, page, fscache_page_radix_pend2store); - - spin_unlock(&cookie->stores_lock); - spin_unlock(&object->lock); - - if (page->index >= op->store_limit) - goto discard_page; - - fscache_stat(&fscache_n_store_pages); - fscache_stat(&fscache_n_cop_write_page); - ret = object->cache->ops->write_page(op, page); - fscache_stat_d(&fscache_n_cop_write_page); - trace_fscache_wrote_page(cookie, page, &op->op, ret); - fscache_end_page_write(object, page); - if (ret < 0) { - fscache_abort_object(object); - fscache_op_complete(&op->op, true); - } else { - fscache_enqueue_operation(&op->op); - } - - _leave(""); - return; - -discard_page: - fscache_stat(&fscache_n_store_pages_over_limit); - trace_fscache_wrote_page(cookie, page, &op->op, -ENOBUFS); - fscache_end_page_write(object, page); - goto again; - -superseded: - /* this writer is going away and there aren't any more things to - * write */ - _debug("cease"); - spin_unlock(&cookie->stores_lock); - clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); - spin_unlock(&object->lock); - fscache_op_complete(&op->op, false); - _leave(""); -} - -/* - * Clear the pages pending writing for invalidation - */ -void fscache_invalidate_writes(struct fscache_cookie *cookie) -{ - struct page *page; - void *results[16]; - int n, i; - - _enter(""); - - for (;;) { - spin_lock(&cookie->stores_lock); - n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, - ARRAY_SIZE(results), - FSCACHE_COOKIE_PENDING_TAG); - if (n == 0) { - spin_unlock(&cookie->stores_lock); - break; - } - - for (i = n - 1; i >= 0; i--) { - page = results[i]; - radix_tree_delete(&cookie->stores, page->index); - trace_fscache_page(cookie, page, fscache_page_radix_delete); - trace_fscache_page(cookie, page, fscache_page_inval); - } - - spin_unlock(&cookie->stores_lock); - - for (i = n - 1; i >= 0; i--) - put_page(results[i]); - } - - wake_up_bit(&cookie->flags, 0); - trace_fscache_wake_cookie(cookie); - - _leave(""); -} - -/* - * request a page be stored in the cache - * - returns: - * -ENOMEM - out of memory, nothing done - * -ENOBUFS - no backing object available in which to cache the page - * 0 - dispatched a write - it'll call end_io_func() when finished - * - * if the cookie still has a backing object at this point, that object can be - * in one of a few states with respect to storage processing: - * - * (1) negative lookup, object not yet created (FSCACHE_COOKIE_CREATING is - * set) - * - * (a) no writes yet - * - * (b) writes deferred till post-creation (mark page for writing and - * return immediately) - * - * (2) negative lookup, object created, initial fill being made from netfs - * - * (a) fill point not yet reached this page (mark page for writing and - * return) - * - * (b) fill point passed this page (queue op to store this page) - * - * (3) object extant (queue op to store this page) - * - * any other state is invalid - */ -int __fscache_write_page(struct fscache_cookie *cookie, - struct page *page, - loff_t object_size, - gfp_t gfp) -{ - struct fscache_storage *op; - struct fscache_object *object; - bool wake_cookie = false; - int ret; - - _enter("%p,%x,", cookie, (u32) page->flags); - - ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); - ASSERT(PageFsCache(page)); - - fscache_stat(&fscache_n_stores); - - if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { - _leave(" = -ENOBUFS [invalidating]"); - return -ENOBUFS; - } - - op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY); - if (!op) - goto nomem; - - fscache_operation_init(cookie, &op->op, fscache_write_op, NULL, - fscache_release_write_op); - op->op.flags = FSCACHE_OP_ASYNC | - (1 << FSCACHE_OP_WAITING) | - (1 << FSCACHE_OP_UNUSE_COOKIE); - - ret = radix_tree_maybe_preload(gfp & ~__GFP_HIGHMEM); - if (ret < 0) - goto nomem_free; - - trace_fscache_page_op(cookie, page, &op->op, fscache_page_op_write_one); - - ret = -ENOBUFS; - spin_lock(&cookie->lock); - - if (!fscache_cookie_enabled(cookie) || - hlist_empty(&cookie->backing_objects)) - goto nobufs; - object = hlist_entry(cookie->backing_objects.first, - struct fscache_object, cookie_link); - if (test_bit(FSCACHE_IOERROR, &object->cache->flags)) - goto nobufs; - - trace_fscache_page(cookie, page, fscache_page_write); - - /* add the page to the pending-storage radix tree on the backing - * object */ - spin_lock(&object->lock); - - if (object->store_limit_l != object_size) - fscache_set_store_limit(object, object_size); - - spin_lock(&cookie->stores_lock); - - _debug("store limit %llx", (unsigned long long) object->store_limit); - - ret = radix_tree_insert(&cookie->stores, page->index, page); - if (ret < 0) { - if (ret == -EEXIST) - goto already_queued; - _debug("insert failed %d", ret); - goto nobufs_unlock_obj; - } - - trace_fscache_page(cookie, page, fscache_page_radix_insert); - radix_tree_tag_set(&cookie->stores, page->index, - FSCACHE_COOKIE_PENDING_TAG); - trace_fscache_page(cookie, page, fscache_page_radix_set_pend); - get_page(page); - - /* we only want one writer at a time, but we do need to queue new - * writers after exclusive ops */ - if (test_and_set_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags)) - goto already_pending; - - spin_unlock(&cookie->stores_lock); - spin_unlock(&object->lock); - - op->op.debug_id = atomic_inc_return(&fscache_op_debug_id); - op->store_limit = object->store_limit; - - __fscache_use_cookie(cookie); - if (fscache_submit_op(object, &op->op) < 0) - goto submit_failed; - - spin_unlock(&cookie->lock); - radix_tree_preload_end(); - fscache_stat(&fscache_n_store_ops); - fscache_stat(&fscache_n_stores_ok); - - /* the work queue now carries its own ref on the object */ - fscache_put_operation(&op->op); - _leave(" = 0"); - return 0; - -already_queued: - fscache_stat(&fscache_n_stores_again); -already_pending: - spin_unlock(&cookie->stores_lock); - spin_unlock(&object->lock); - spin_unlock(&cookie->lock); - radix_tree_preload_end(); - fscache_put_operation(&op->op); - fscache_stat(&fscache_n_stores_ok); - _leave(" = 0"); - return 0; - -submit_failed: - spin_lock(&cookie->stores_lock); - radix_tree_delete(&cookie->stores, page->index); - trace_fscache_page(cookie, page, fscache_page_radix_delete); - spin_unlock(&cookie->stores_lock); - wake_cookie = __fscache_unuse_cookie(cookie); - put_page(page); - ret = -ENOBUFS; - goto nobufs; - -nobufs_unlock_obj: - spin_unlock(&cookie->stores_lock); - spin_unlock(&object->lock); -nobufs: - spin_unlock(&cookie->lock); - radix_tree_preload_end(); - fscache_put_operation(&op->op); - if (wake_cookie) - __fscache_wake_unused_cookie(cookie); - fscache_stat(&fscache_n_stores_nobufs); - _leave(" = -ENOBUFS"); - return -ENOBUFS; - -nomem_free: - fscache_put_operation(&op->op); -nomem: - fscache_stat(&fscache_n_stores_oom); - _leave(" = -ENOMEM"); - return -ENOMEM; -} -EXPORT_SYMBOL(__fscache_write_page); - -/* - * remove a page from the cache - */ -void __fscache_uncache_page(struct fscache_cookie *cookie, struct page *page) -{ - struct fscache_object *object; - - _enter(",%p", page); - - ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); - ASSERTCMP(page, !=, NULL); - - fscache_stat(&fscache_n_uncaches); - - /* cache withdrawal may beat us to it */ - if (!PageFsCache(page)) - goto done; - - trace_fscache_page(cookie, page, fscache_page_uncache); - - /* get the object */ - spin_lock(&cookie->lock); - - if (hlist_empty(&cookie->backing_objects)) { - ClearPageFsCache(page); - goto done_unlock; - } - - object = hlist_entry(cookie->backing_objects.first, - struct fscache_object, cookie_link); - - /* there might now be stuff on disk we could read */ - clear_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags); - - /* only invoke the cache backend if we managed to mark the page - * uncached here; this deals with synchronisation vs withdrawal */ - if (TestClearPageFsCache(page) && - object->cache->ops->uncache_page) { - /* the cache backend releases the cookie lock */ - fscache_stat(&fscache_n_cop_uncache_page); - object->cache->ops->uncache_page(object, page); - fscache_stat_d(&fscache_n_cop_uncache_page); - goto done; - } - -done_unlock: - spin_unlock(&cookie->lock); -done: - _leave(""); -} -EXPORT_SYMBOL(__fscache_uncache_page); - -/** - * fscache_mark_page_cached - Mark a page as being cached - * @op: The retrieval op pages are being marked for - * @page: The page to be marked - * - * Mark a netfs page as being cached. After this is called, the netfs - * must call fscache_uncache_page() to remove the mark. - */ -void fscache_mark_page_cached(struct fscache_retrieval *op, struct page *page) -{ - struct fscache_cookie *cookie = op->op.object->cookie; - -#ifdef CONFIG_FSCACHE_STATS - atomic_inc(&fscache_n_marks); -#endif - - trace_fscache_page(cookie, page, fscache_page_cached); - - _debug("- mark %p{%lx}", page, page->index); - if (TestSetPageFsCache(page)) { - static bool once_only; - if (!once_only) { - once_only = true; - pr_warn("Cookie type %s marked page %lx multiple times\n", - cookie->def->name, page->index); - } - } - - if (cookie->def->mark_page_cached) - cookie->def->mark_page_cached(cookie->netfs_data, - op->mapping, page); -} -EXPORT_SYMBOL(fscache_mark_page_cached); - -/** - * fscache_mark_pages_cached - Mark pages as being cached - * @op: The retrieval op pages are being marked for - * @pagevec: The pages to be marked - * - * Mark a bunch of netfs pages as being cached. After this is called, - * the netfs must call fscache_uncache_page() to remove the mark. - */ -void fscache_mark_pages_cached(struct fscache_retrieval *op, - struct pagevec *pagevec) -{ - unsigned long loop; - - for (loop = 0; loop < pagevec->nr; loop++) - fscache_mark_page_cached(op, pagevec->pages[loop]); - - pagevec_reinit(pagevec); -} -EXPORT_SYMBOL(fscache_mark_pages_cached); - -/* - * Uncache all the pages in an inode that are marked PG_fscache, assuming them - * to be associated with the given cookie. - */ -void __fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, - struct inode *inode) -{ - struct address_space *mapping = inode->i_mapping; - struct pagevec pvec; - pgoff_t next; - int i; - - _enter("%p,%p", cookie, inode); - - if (!mapping || mapping->nrpages == 0) { - _leave(" [no pages]"); - return; - } - - pagevec_init(&pvec); - next = 0; - do { - if (!pagevec_lookup(&pvec, mapping, &next)) - break; - for (i = 0; i < pagevec_count(&pvec); i++) { - struct page *page = pvec.pages[i]; - if (PageFsCache(page)) { - __fscache_wait_on_page_write(cookie, page); - __fscache_uncache_page(cookie, page); - } - } - pagevec_release(&pvec); - cond_resched(); - } while (next); - - _leave(""); -} -EXPORT_SYMBOL(__fscache_uncache_all_inode_pages); diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c index 3ffa34c99977..4cefce5bf4cd 100644 --- a/fs/fscache/stats.c +++ b/fs/fscache/stats.c @@ -127,7 +127,6 @@ atomic_t fscache_n_cop_allocate_page; atomic_t fscache_n_cop_allocate_pages; atomic_t fscache_n_cop_write_page; atomic_t fscache_n_cop_uncache_page; -atomic_t fscache_n_cop_dissociate_pages; atomic_t fscache_n_cache_no_space_reject; atomic_t fscache_n_cache_stale_objects; @@ -271,14 +270,13 @@ int fscache_stats_show(struct seq_file *m, void *v) atomic_read(&fscache_n_cop_put_object), atomic_read(&fscache_n_cop_attr_changed), atomic_read(&fscache_n_cop_sync_cache)); - seq_printf(m, "CacheOp: rap=%d ras=%d alp=%d als=%d wrp=%d ucp=%d dsp=%d\n", + seq_printf(m, "CacheOp: rap=%d ras=%d alp=%d als=%d wrp=%d ucp=%d\n", atomic_read(&fscache_n_cop_read_or_alloc_page), atomic_read(&fscache_n_cop_read_or_alloc_pages), atomic_read(&fscache_n_cop_allocate_page), atomic_read(&fscache_n_cop_allocate_pages), atomic_read(&fscache_n_cop_write_page), - atomic_read(&fscache_n_cop_uncache_page), - atomic_read(&fscache_n_cop_dissociate_pages)); + atomic_read(&fscache_n_cop_uncache_page)); seq_printf(m, "CacheEv: nsp=%d stl=%d rtr=%d cul=%d\n", atomic_read(&fscache_n_cache_no_space_reject), atomic_read(&fscache_n_cache_stale_objects), diff --git a/fs/nfs/fscache-index.c b/fs/nfs/fscache-index.c index 573b1da9342c..4bd5ce736193 100644 --- a/fs/nfs/fscache-index.c +++ b/fs/nfs/fscache-index.c @@ -98,30 +98,6 @@ enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data, return FSCACHE_CHECKAUX_OKAY; } -/* - * Get an extra reference on a read context. - * - This function can be absent if the completion function doesn't require a - * context. - * - The read context is passed back to NFS in the event that a data read on the - * cache fails with EIO - in which case the server must be contacted to - * retrieve the data, which requires the read context for security. - */ -static void nfs_fh_get_context(void *cookie_netfs_data, void *context) -{ - get_nfs_open_context(context); -} - -/* - * Release an extra reference on a read context. - * - This function can be absent if the completion function doesn't require a - * context. - */ -static void nfs_fh_put_context(void *cookie_netfs_data, void *context) -{ - if (context) - put_nfs_open_context(context); -} - /* * Define the inode object for FS-Cache. This is used to describe an inode * object to fscache_acquire_cookie(). It is keyed by the NFS file handle for @@ -135,6 +111,4 @@ const struct fscache_cookie_def nfs_fscache_inode_object_def = { .name = "NFS.fh", .type = FSCACHE_COOKIE_TYPE_DATAFILE, .check_aux = nfs_fscache_inode_check_aux, - .get_context = nfs_fh_get_context, - .put_context = nfs_fh_put_context, }; diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h index efa9b6f9fab1..5e610f9a524c 100644 --- a/include/linux/fscache-cache.h +++ b/include/linux/fscache-cache.h @@ -137,87 +137,6 @@ extern void fscache_operation_init(struct fscache_cookie *, fscache_operation_cancel_t, fscache_operation_release_t); -/* - * data read operation - */ -struct fscache_retrieval { - struct fscache_operation op; - struct fscache_cookie *cookie; /* The netfs cookie */ - struct address_space *mapping; /* netfs pages */ - fscache_rw_complete_t end_io_func; /* function to call on I/O completion */ - void *context; /* netfs read context (pinned) */ - struct list_head to_do; /* list of things to be done by the backend */ - atomic_t n_pages; /* number of pages to be retrieved */ -}; - -typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op, - struct page *page, - gfp_t gfp); - -typedef int (*fscache_pages_retrieval_func_t)(struct fscache_retrieval *op, - struct list_head *pages, - unsigned *nr_pages, - gfp_t gfp); - -/** - * fscache_get_retrieval - Get an extra reference on a retrieval operation - * @op: The retrieval operation to get a reference on - * - * Get an extra reference on a retrieval operation. - */ -static inline -struct fscache_retrieval *fscache_get_retrieval(struct fscache_retrieval *op) -{ - atomic_inc(&op->op.usage); - return op; -} - -/** - * fscache_enqueue_retrieval - Enqueue a retrieval operation for processing - * @op: The retrieval operation affected - * - * Enqueue a retrieval operation for processing by the FS-Cache thread pool. - */ -static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op) -{ - fscache_enqueue_operation(&op->op); -} - -/** - * fscache_retrieval_complete - Record (partial) completion of a retrieval - * @op: The retrieval operation affected - * @n_pages: The number of pages to account for - */ -static inline void fscache_retrieval_complete(struct fscache_retrieval *op, - int n_pages) -{ - if (atomic_sub_return_relaxed(n_pages, &op->n_pages) <= 0) - fscache_op_complete(&op->op, false); -} - -/** - * fscache_put_retrieval - Drop a reference to a retrieval operation - * @op: The retrieval operation affected - * - * Drop a reference to a retrieval operation. - */ -static inline void fscache_put_retrieval(struct fscache_retrieval *op) -{ - fscache_put_operation(&op->op); -} - -/* - * cached page storage work item - * - used to do three things: - * - batch writes to the cache - * - do cache writes asynchronously - * - defer writes until cache object lookup completion - */ -struct fscache_storage { - struct fscache_operation op; - pgoff_t store_limit; /* don't write more than this */ -}; - /* * cache operations */ @@ -275,35 +194,6 @@ struct fscache_cache_ops { /* reserve space for an object's data and associated metadata */ int (*reserve_space)(struct fscache_object *object, loff_t i_size); - /* request a backing block for a page be read or allocated in the - * cache */ - fscache_page_retrieval_func_t read_or_alloc_page; - - /* request backing blocks for a list of pages be read or allocated in - * the cache */ - fscache_pages_retrieval_func_t read_or_alloc_pages; - - /* request a backing block for a page be allocated in the cache so that - * it can be written directly */ - fscache_page_retrieval_func_t allocate_page; - - /* request backing blocks for pages be allocated in the cache so that - * they can be written directly */ - fscache_pages_retrieval_func_t allocate_pages; - - /* write a page to its backing block in the cache */ - int (*write_page)(struct fscache_storage *op, struct page *page); - - /* detach backing block from a page (optional) - * - must release the cookie lock before returning - * - may sleep - */ - void (*uncache_page)(struct fscache_object *object, - struct page *page); - - /* dissociate a cache from all the pages it was backing */ - void (*dissociate_pages)(struct fscache_cache *cache); - /* Begin an operation for the netfs lib */ int (*begin_operation)(struct netfs_cache_resources *cres, struct fscache_operation *op); @@ -466,21 +356,6 @@ void fscache_set_store_limit(struct fscache_object *object, loff_t i_size) object->store_limit++; } -/** - * fscache_end_io - End a retrieval operation on a page - * @op: The FS-Cache operation covering the retrieval - * @page: The page that was to be fetched - * @error: The error code (0 if successful) - * - * Note the end of an operation to retrieve a page, as covered by a particular - * operation record. - */ -static inline void fscache_end_io(struct fscache_retrieval *op, - struct page *page, int error) -{ - op->end_io_func(page, op->context, error); -} - static inline void __fscache_use_cookie(struct fscache_cookie *cookie) { atomic_inc(&cookie->n_active); @@ -538,12 +413,6 @@ extern void fscache_withdraw_cache(struct fscache_cache *cache); extern void fscache_io_error(struct fscache_cache *cache); -extern void fscache_mark_page_cached(struct fscache_retrieval *op, - struct page *page); - -extern void fscache_mark_pages_cached(struct fscache_retrieval *op, - struct pagevec *pagevec); - extern bool fscache_object_sleep_till_congested(signed long *timeoutp); extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object, diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 715fb830e982..01558d155799 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -37,10 +37,6 @@ struct fscache_cookie; struct fscache_netfs; struct netfs_read_request; -typedef void (*fscache_rw_complete_t)(struct page *page, - void *context, - int error); - /* result of index entry consultation */ enum fscache_checkaux { FSCACHE_CHECKAUX_OKAY, /* entry okay as is */ @@ -79,27 +75,6 @@ struct fscache_cookie_def { const void *data, uint16_t datalen, loff_t object_size); - - /* get an extra reference on a read context - * - this function can be absent if the completion function doesn't - * require a context - */ - void (*get_context)(void *cookie_netfs_data, void *context); - - /* release an extra reference on a read context - * - this function can be absent if the completion function doesn't - * require a context - */ - void (*put_context)(void *cookie_netfs_data, void *context); - - /* indicate page that now have cache metadata retained - * - this function should mark the specified page as now being cached - * - the page will have been marked with PG_fscache before this is - * called, so this is optional - */ - void (*mark_page_cached)(void *cookie_netfs_data, - struct address_space *mapping, - struct page *page); }; /* @@ -126,16 +101,12 @@ struct fscache_cookie { atomic_t n_active; /* number of active users of netfs ptrs */ unsigned int debug_id; spinlock_t lock; - spinlock_t stores_lock; /* lock on page store tree */ struct hlist_head backing_objects; /* object(s) backing this file/index */ const struct fscache_cookie_def *def; /* definition */ struct fscache_cookie *parent; /* parent of this entry */ struct hlist_bl_node hash_link; /* Link in hash table */ struct list_head proc_link; /* Link in proc list */ void *netfs_data; /* back pointer to netfs */ - struct radix_tree_root stores; /* pages to be stored on this cookie */ -#define FSCACHE_COOKIE_PENDING_TAG 0 /* pages tag: pending write to cache */ -#define FSCACHE_COOKIE_STORING_TAG 1 /* pages tag: writing to cache */ unsigned long flags; #define FSCACHE_COOKIE_LOOKING_UP 0 /* T if non-index cookie being looked up still */ @@ -193,7 +164,6 @@ extern void __fscache_update_cookie(struct fscache_cookie *, const void *); extern int __fscache_attr_changed(struct fscache_cookie *); extern void __fscache_invalidate(struct fscache_cookie *); extern void __fscache_wait_on_invalidate(struct fscache_cookie *); - #ifdef FSCACHE_USE_NEW_IO_API extern int __fscache_begin_operation(struct netfs_cache_resources *, struct fscache_cookie *, bool); @@ -202,33 +172,6 @@ extern int __fscache_begin_operation(struct netfs_cache_resources *, struct fsca extern int __fscache_fallback_read_page(struct fscache_cookie *, struct page *); extern int __fscache_fallback_write_page(struct fscache_cookie *, struct page *); #endif -#ifdef FSCACHE_USE_OLD_IO_API -extern int __fscache_read_or_alloc_page(struct fscache_cookie *, - struct page *, - fscache_rw_complete_t, - void *, - gfp_t); -extern int __fscache_read_or_alloc_pages(struct fscache_cookie *, - struct address_space *, - struct list_head *, - unsigned *, - fscache_rw_complete_t, - void *, - gfp_t); -extern int __fscache_alloc_page(struct fscache_cookie *, struct page *, gfp_t); -extern int __fscache_write_page(struct fscache_cookie *, struct page *, loff_t, gfp_t); -extern void __fscache_uncache_page(struct fscache_cookie *, struct page *); -extern bool __fscache_check_page_write(struct fscache_cookie *, struct page *); -extern void __fscache_wait_on_page_write(struct fscache_cookie *, struct page *); -extern bool __fscache_maybe_release_page(struct fscache_cookie *, struct page *, - gfp_t); -extern void __fscache_uncache_all_inode_pages(struct fscache_cookie *, - struct inode *); -extern void __fscache_readpages_cancel(struct fscache_cookie *cookie, - struct list_head *pages); - -#endif /* FSCACHE_USE_OLD_IO_API */ - extern void __fscache_disable_cookie(struct fscache_cookie *, const void *, bool); extern void __fscache_enable_cookie(struct fscache_cookie *, const void *, loff_t, bool (*)(void *), void *); @@ -495,24 +438,6 @@ void fscache_wait_on_invalidate(struct fscache_cookie *cookie) __fscache_wait_on_invalidate(cookie); } -/** - * fscache_reserve_space - Reserve data space for a cached object - * @cookie: The cookie representing the cache object - * @i_size: The amount of space to be reserved - * - * Reserve an amount of space in the cache for the cache object attached to a - * cookie so that a write to that object within the space can always be - * honoured. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -int fscache_reserve_space(struct fscache_cookie *cookie, loff_t size) -{ - return -ENOBUFS; -} - #ifdef FSCACHE_USE_NEW_IO_API /** @@ -619,289 +544,6 @@ int fscache_write(struct netfs_cache_resources *cres, #endif /* FSCACHE_USE_NEW_IO_API */ -#ifdef FSCACHE_USE_OLD_IO_API - -/** - * fscache_read_or_alloc_page - Read a page from the cache or allocate a block - * in which to store it - * @cookie: The cookie representing the cache object - * @page: The netfs page to fill if possible - * @end_io_func: The callback to invoke when and if the page is filled - * @context: An arbitrary piece of data to pass on to end_io_func() - * @gfp: The conditions under which memory allocation should be made - * - * Read a page from the cache, or if that's not possible make a potential - * one-block reservation in the cache into which the page may be stored once - * fetched from the server. - * - * If the page is not backed by the cache object, or if it there's some reason - * it can't be, -ENOBUFS will be returned and nothing more will be done for - * that page. - * - * Else, if that page is backed by the cache, a read will be initiated directly - * to the netfs's page and 0 will be returned by this function. The - * end_io_func() callback will be invoked when the operation terminates on a - * completion or failure. Note that the callback may be invoked before the - * return. - * - * Else, if the page is unbacked, -ENODATA is returned and a block may have - * been allocated in the cache. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -int fscache_read_or_alloc_page(struct fscache_cookie *cookie, - struct page *page, - fscache_rw_complete_t end_io_func, - void *context, - gfp_t gfp) -{ - if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_read_or_alloc_page(cookie, page, end_io_func, - context, gfp); - else - return -ENOBUFS; -} - -/** - * fscache_read_or_alloc_pages - Read pages from the cache and/or allocate - * blocks in which to store them - * @cookie: The cookie representing the cache object - * @mapping: The netfs inode mapping to which the pages will be attached - * @pages: A list of potential netfs pages to be filled - * @nr_pages: Number of pages to be read and/or allocated - * @end_io_func: The callback to invoke when and if each page is filled - * @context: An arbitrary piece of data to pass on to end_io_func() - * @gfp: The conditions under which memory allocation should be made - * - * Read a set of pages from the cache, or if that's not possible, attempt to - * make a potential one-block reservation for each page in the cache into which - * that page may be stored once fetched from the server. - * - * If some pages are not backed by the cache object, or if it there's some - * reason they can't be, -ENOBUFS will be returned and nothing more will be - * done for that pages. - * - * Else, if some of the pages are backed by the cache, a read will be initiated - * directly to the netfs's page and 0 will be returned by this function. The - * end_io_func() callback will be invoked when the operation terminates on a - * completion or failure. Note that the callback may be invoked before the - * return. - * - * Else, if a page is unbacked, -ENODATA is returned and a block may have - * been allocated in the cache. - * - * Because the function may want to return all of -ENOBUFS, -ENODATA and 0 in - * regard to different pages, the return values are prioritised in that order. - * Any pages submitted for reading are removed from the pages list. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -int fscache_read_or_alloc_pages(struct fscache_cookie *cookie, - struct address_space *mapping, - struct list_head *pages, - unsigned *nr_pages, - fscache_rw_complete_t end_io_func, - void *context, - gfp_t gfp) -{ - if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_read_or_alloc_pages(cookie, mapping, pages, - nr_pages, end_io_func, - context, gfp); - else - return -ENOBUFS; -} - -/** - * fscache_alloc_page - Allocate a block in which to store a page - * @cookie: The cookie representing the cache object - * @page: The netfs page to allocate a page for - * @gfp: The conditions under which memory allocation should be made - * - * Request Allocation a block in the cache in which to store a netfs page - * without retrieving any contents from the cache. - * - * If the page is not backed by a file then -ENOBUFS will be returned and - * nothing more will be done, and no reservation will be made. - * - * Else, a block will be allocated if one wasn't already, and 0 will be - * returned - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -int fscache_alloc_page(struct fscache_cookie *cookie, - struct page *page, - gfp_t gfp) -{ - if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_alloc_page(cookie, page, gfp); - else - return -ENOBUFS; -} - -/** - * fscache_readpages_cancel - Cancel read/alloc on pages - * @cookie: The cookie representing the inode's cache object. - * @pages: The netfs pages that we canceled write on in readpages() - * - * Uncache/unreserve the pages reserved earlier in readpages() via - * fscache_readpages_or_alloc() and similar. In most successful caches in - * readpages() this doesn't do anything. In cases when the underlying netfs's - * readahead failed we need to clean up the pagelist (unmark and uncache). - * - * This function may sleep as it may have to clean up disk state. - */ -static inline -void fscache_readpages_cancel(struct fscache_cookie *cookie, - struct list_head *pages) -{ - if (fscache_cookie_valid(cookie)) - __fscache_readpages_cancel(cookie, pages); -} - -/** - * fscache_write_page - Request storage of a page in the cache - * @cookie: The cookie representing the cache object - * @page: The netfs page to store - * @object_size: Updated size of object - * @gfp: The conditions under which memory allocation should be made - * - * Request the contents of the netfs page be written into the cache. This - * request may be ignored if no cache block is currently allocated, in which - * case it will return -ENOBUFS. - * - * If a cache block was already allocated, a write will be initiated and 0 will - * be returned. The PG_fscache_write page bit is set immediately and will then - * be cleared at the completion of the write to indicate the success or failure - * of the operation. Note that the completion may happen before the return. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -int fscache_write_page(struct fscache_cookie *cookie, - struct page *page, - loff_t object_size, - gfp_t gfp) -{ - if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie)) - return __fscache_write_page(cookie, page, object_size, gfp); - else - return -ENOBUFS; -} - -/** - * fscache_uncache_page - Indicate that caching is no longer required on a page - * @cookie: The cookie representing the cache object - * @page: The netfs page that was being cached. - * - * Tell the cache that we no longer want a page to be cached and that it should - * remove any knowledge of the netfs page it may have. - * - * Note that this cannot cancel any outstanding I/O operations between this - * page and the cache. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -void fscache_uncache_page(struct fscache_cookie *cookie, - struct page *page) -{ - if (fscache_cookie_valid(cookie)) - __fscache_uncache_page(cookie, page); -} - -/** - * fscache_check_page_write - Ask if a page is being writing to the cache - * @cookie: The cookie representing the cache object - * @page: The netfs page that is being cached. - * - * Ask the cache if a page is being written to the cache. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -bool fscache_check_page_write(struct fscache_cookie *cookie, - struct page *page) -{ - if (fscache_cookie_valid(cookie)) - return __fscache_check_page_write(cookie, page); - return false; -} - -/** - * fscache_wait_on_page_write - Wait for a page to complete writing to the cache - * @cookie: The cookie representing the cache object - * @page: The netfs page that is being cached. - * - * Ask the cache to wake us up when a page is no longer being written to the - * cache. - * - * See Documentation/filesystems/caching/netfs-api.rst for a complete - * description. - */ -static inline -void fscache_wait_on_page_write(struct fscache_cookie *cookie, - struct page *page) -{ - if (fscache_cookie_valid(cookie)) - __fscache_wait_on_page_write(cookie, page); -} - -/** - * fscache_maybe_release_page - Consider releasing a page, cancelling a store - * @cookie: The cookie representing the cache object - * @page: The netfs page that is being cached. - * @gfp: The gfp flags passed to releasepage() - * - * Consider releasing a page for the vmscan algorithm, on behalf of the netfs's - * releasepage() call. A storage request on the page may cancelled if it is - * not currently being processed. - * - * The function returns true if the page no longer has a storage request on it, - * and false if a storage request is left in place. If true is returned, the - * page will have been passed to fscache_uncache_page(). If false is returned - * the page cannot be freed yet. - */ -static inline -bool fscache_maybe_release_page(struct fscache_cookie *cookie, - struct page *page, - gfp_t gfp) -{ - if (fscache_cookie_valid(cookie) && PageFsCache(page)) - return __fscache_maybe_release_page(cookie, page, gfp); - return true; -} - -/** - * fscache_uncache_all_inode_pages - Uncache all an inode's pages - * @cookie: The cookie representing the inode's cache object. - * @inode: The inode to uncache pages from. - * - * Uncache all the pages in an inode that are marked PG_fscache, assuming them - * to be associated with the given cookie. - * - * This function may sleep. It will wait for pages that are being written out - * and will wait whilst the PG_fscache mark is removed by the cache. - */ -static inline -void fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, - struct inode *inode) -{ - if (fscache_cookie_valid(cookie)) - __fscache_uncache_all_inode_pages(cookie, inode); -} - -#endif /* FSCACHE_USE_OLD_IO_API */ - /** * fscache_disable_cookie - Disable a cookie * @cookie: The cookie representing the cache object
