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Subject[RFC PATCH 05/76] fscache: Remove the old I/O API
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Date
Remove the old fscache I/O API.  There's no point trying to transform it as
the new one will bear no similarities to the old one.

Signed-off-by: David Howells <dhowells@redhat.com>
---

fs/cachefiles/Makefile | 1
fs/cachefiles/interface.c | 15 -
fs/cachefiles/internal.h | 38 -
fs/cachefiles/main.c | 1
fs/cachefiles/rdwr.c | 975 -----------------------------------
fs/fscache/cache.c | 6
fs/fscache/cookie.c | 10
fs/fscache/internal.h | 23 -
fs/fscache/object.c | 2
fs/fscache/page.c | 1068 --------------------------------------
fs/fscache/stats.c | 6
include/linux/fscache-cache.h | 132 -----
include/linux/fscache-obsolete.h | 13
include/linux/fscache.h | 349 ------------
14 files changed, 15 insertions(+), 2624 deletions(-)
delete mode 100644 fs/cachefiles/rdwr.c
create mode 100644 include/linux/fscache-obsolete.h

diff --git a/fs/cachefiles/Makefile b/fs/cachefiles/Makefile
index 891dedda5905..3455d3646547 100644
--- a/fs/cachefiles/Makefile
+++ b/fs/cachefiles/Makefile
@@ -10,7 +10,6 @@ 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 4cea5fbf695e..04d92ad402a4 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,
@@ -560,12 +552,5 @@ 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,
};
diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h
index cf9bd6401c2d..aca73c8403ab 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
*/
@@ -202,21 +179,6 @@ void cachefiles_hist(atomic_t histogram[], unsigned long start_jif)
#define cachefiles_hist(hist, start_jif) do {} while (0)
#endif

-/*
- * 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 *);
-
/*
* security.c
*/
diff --git a/fs/cachefiles/main.c b/fs/cachefiles/main.c
index ddf0cd58d60c..3f0101a74809 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 8bda092e60c5..000000000000
--- a/fs/cachefiles/rdwr.c
+++ /dev/null
@@ -1,975 +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@redhat.com)
- */
-
-#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_bit_key *key = _key;
- struct page *page = wait->private;
-
- ASSERT(key);
-
- _enter("{%lu},%u,%d,{%p,%u}",
- monitor->netfs_page->index, mode, sync,
- key->flags, key->bit_nr);
-
- if (key->flags != &page->flags ||
- 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));
- ASSERT(inode->i_mapping->a_ops->readpages);
-
- /* 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));
- ASSERT(inode->i_mapping->a_ops->readpages);
-
- /* 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 fcc136361415..7de6d4cd29ee 100644
--- a/fs/fscache/cache.c
+++ b/fs/fscache/cache.c
@@ -382,12 +382,6 @@ 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 c7047544972b..b35f727cc0d4 100644
--- a/fs/fscache/cookie.c
+++ b/fs/fscache/cookie.c
@@ -191,13 +191,8 @@ 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);
@@ -786,10 +781,6 @@ 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);
@@ -838,7 +829,6 @@ 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(atomic_read(&cookie->parent->usage), >, 0);
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index 4b535c2dae4a..83dfbe0e3964 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -142,7 +142,6 @@ 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 *);

/*
* proc.c
@@ -272,7 +271,6 @@ 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;
@@ -325,27 +323,6 @@ static inline void fscache_cookie_get(struct fscache_cookie *cookie,
trace_fscache_cookie(cookie, where, usage);
}

-/*
- * 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 cb2146e02cd5..3d7f956a01c6 100644
--- a/fs/fscache/object.c
+++ b/fs/fscache/object.c
@@ -973,14 +973,12 @@ 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 26af6fdf1538..1beffb071205 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -13,174 +13,6 @@
#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
*/
@@ -265,76 +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);
-
- fscache_hist(fscache_retrieval_histogram, op->start_time);
- if (op->context)
- fscache_put_context(op->cookie, op->context);
-
- _leave("");
-}
-
-/*
- * allocate a retrieval op
- */
-static 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;
- op->start_time = jiffies;
- 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
*/
@@ -416,833 +178,3 @@ 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 a5aa93ece8c5..281022871e70 100644
--- a/fs/fscache/stats.c
+++ b/fs/fscache/stats.c
@@ -124,7 +124,6 @@ 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;
@@ -265,14 +264,13 @@ 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/include/linux/fscache-cache.h b/include/linux/fscache-cache.h
index 3f0b19dcfae7..f01fe979b323 100644
--- a/include/linux/fscache-cache.h
+++ b/include/linux/fscache-cache.h
@@ -137,88 +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 */
- unsigned long start_time; /* time at which retrieval started */
- 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 +193,6 @@ 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);
};

extern struct fscache_cookie fscache_fsdef_index;
@@ -466,21 +355,6 @@ 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 +412,6 @@ 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-obsolete.h b/include/linux/fscache-obsolete.h
new file mode 100644
index 000000000000..8d6d3a3b0d0a
--- /dev/null
+++ b/include/linux/fscache-obsolete.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Obsolete fscache bits
+ *
+ * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _LINUX_FSCACHE_OBSOLETE_H
+#define _LINUX_FSCACHE_OBSOLETE_H
+
+
+
+#endif /* _LINUX_FSCACHE_OBSOLETE_H */
diff --git a/include/linux/fscache.h b/include/linux/fscache.h
index 2606fe7edd29..143d48281117 100644
--- a/include/linux/fscache.h
+++ b/include/linux/fscache.h
@@ -47,10 +47,6 @@ struct fscache_cache_tag;
struct fscache_cookie;
struct fscache_netfs;

-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 */
@@ -89,27 +85,6 @@ 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);
};

/*
@@ -136,16 +111,12 @@ 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 */
@@ -202,29 +173,6 @@ 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 *);
-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);
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 *);
@@ -491,303 +439,6 @@ 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;
-}
-
-/**
- * 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);
-}
-
/**
* fscache_disable_cookie - Disable a cookie
* @cookie: The cookie representing the cache object

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