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-rw-r--r--fs/fscache/io.c327
1 files changed, 0 insertions, 327 deletions
diff --git a/fs/fscache/io.c b/fs/fscache/io.c
deleted file mode 100644
index 0d2b8dec8f..0000000000
--- a/fs/fscache/io.c
+++ /dev/null
@@ -1,327 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/* Cache data I/O routines
- *
- * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- */
-#define FSCACHE_DEBUG_LEVEL OPERATION
-#include <linux/fscache-cache.h>
-#include <linux/uio.h>
-#include <linux/bvec.h>
-#include <linux/slab.h>
-#include <linux/uio.h>
-#include "internal.h"
-
-/**
- * fscache_wait_for_operation - Wait for an object become accessible
- * @cres: The cache resources for the operation being performed
- * @want_state: The minimum state the object must be at
- *
- * See if the target cache object is at the specified minimum state of
- * accessibility yet, and if not, wait for it.
- */
-bool fscache_wait_for_operation(struct netfs_cache_resources *cres,
- enum fscache_want_state want_state)
-{
- struct fscache_cookie *cookie = fscache_cres_cookie(cres);
- enum fscache_cookie_state state;
-
-again:
- if (!fscache_cache_is_live(cookie->volume->cache)) {
- _leave(" [broken]");
- return false;
- }
-
- state = fscache_cookie_state(cookie);
- _enter("c=%08x{%u},%x", cookie->debug_id, state, want_state);
-
- switch (state) {
- case FSCACHE_COOKIE_STATE_CREATING:
- case FSCACHE_COOKIE_STATE_INVALIDATING:
- if (want_state == FSCACHE_WANT_PARAMS)
- goto ready; /* There can be no content */
- fallthrough;
- case FSCACHE_COOKIE_STATE_LOOKING_UP:
- case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
- wait_var_event(&cookie->state,
- fscache_cookie_state(cookie) != state);
- goto again;
-
- case FSCACHE_COOKIE_STATE_ACTIVE:
- goto ready;
- case FSCACHE_COOKIE_STATE_DROPPED:
- case FSCACHE_COOKIE_STATE_RELINQUISHING:
- default:
- _leave(" [not live]");
- return false;
- }
-
-ready:
- if (!cres->cache_priv2)
- return cookie->volume->cache->ops->begin_operation(cres, want_state);
- return true;
-}
-EXPORT_SYMBOL(fscache_wait_for_operation);
-
-/*
- * Begin an I/O operation on the cache, waiting till we reach the right state.
- *
- * Attaches the resources required to the operation resources record.
- */
-static int fscache_begin_operation(struct netfs_cache_resources *cres,
- struct fscache_cookie *cookie,
- enum fscache_want_state want_state,
- enum fscache_access_trace why)
-{
- enum fscache_cookie_state state;
- long timeo;
- bool once_only = false;
-
- cres->ops = NULL;
- cres->cache_priv = cookie;
- cres->cache_priv2 = NULL;
- cres->debug_id = cookie->debug_id;
- cres->inval_counter = cookie->inval_counter;
-
- if (!fscache_begin_cookie_access(cookie, why))
- return -ENOBUFS;
-
-again:
- spin_lock(&cookie->lock);
-
- state = fscache_cookie_state(cookie);
- _enter("c=%08x{%u},%x", cookie->debug_id, state, want_state);
-
- switch (state) {
- case FSCACHE_COOKIE_STATE_LOOKING_UP:
- case FSCACHE_COOKIE_STATE_LRU_DISCARDING:
- case FSCACHE_COOKIE_STATE_INVALIDATING:
- goto wait_for_file_wrangling;
- case FSCACHE_COOKIE_STATE_CREATING:
- if (want_state == FSCACHE_WANT_PARAMS)
- goto ready; /* There can be no content */
- goto wait_for_file_wrangling;
- case FSCACHE_COOKIE_STATE_ACTIVE:
- goto ready;
- case FSCACHE_COOKIE_STATE_DROPPED:
- case FSCACHE_COOKIE_STATE_RELINQUISHING:
- WARN(1, "Can't use cookie in state %u\n", cookie->state);
- goto not_live;
- default:
- goto not_live;
- }
-
-ready:
- spin_unlock(&cookie->lock);
- if (!cookie->volume->cache->ops->begin_operation(cres, want_state))
- goto failed;
- return 0;
-
-wait_for_file_wrangling:
- spin_unlock(&cookie->lock);
- trace_fscache_access(cookie->debug_id, refcount_read(&cookie->ref),
- atomic_read(&cookie->n_accesses),
- fscache_access_io_wait);
- timeo = wait_var_event_timeout(&cookie->state,
- fscache_cookie_state(cookie) != state, 20 * HZ);
- if (timeo <= 1 && !once_only) {
- pr_warn("%s: cookie state change wait timed out: cookie->state=%u state=%u",
- __func__, fscache_cookie_state(cookie), state);
- fscache_print_cookie(cookie, 'O');
- once_only = true;
- }
- goto again;
-
-not_live:
- spin_unlock(&cookie->lock);
-failed:
- cres->cache_priv = NULL;
- cres->ops = NULL;
- fscache_end_cookie_access(cookie, fscache_access_io_not_live);
- _leave(" = -ENOBUFS");
- return -ENOBUFS;
-}
-
-int __fscache_begin_read_operation(struct netfs_cache_resources *cres,
- struct fscache_cookie *cookie)
-{
- return fscache_begin_operation(cres, cookie, FSCACHE_WANT_PARAMS,
- fscache_access_io_read);
-}
-EXPORT_SYMBOL(__fscache_begin_read_operation);
-
-int __fscache_begin_write_operation(struct netfs_cache_resources *cres,
- struct fscache_cookie *cookie)
-{
- return fscache_begin_operation(cres, cookie, FSCACHE_WANT_PARAMS,
- fscache_access_io_write);
-}
-EXPORT_SYMBOL(__fscache_begin_write_operation);
-
-/**
- * fscache_dirty_folio - Mark folio dirty and pin a cache object for writeback
- * @mapping: The mapping the folio belongs to.
- * @folio: The folio being dirtied.
- * @cookie: The cookie referring to the cache object
- *
- * Set the dirty flag on a folio and pin an in-use cache object in memory
- * so that writeback can later write to it. This is intended
- * to be called from the filesystem's ->dirty_folio() method.
- *
- * Return: true if the dirty flag was set on the folio, false otherwise.
- */
-bool fscache_dirty_folio(struct address_space *mapping, struct folio *folio,
- struct fscache_cookie *cookie)
-{
- struct inode *inode = mapping->host;
- bool need_use = false;
-
- _enter("");
-
- if (!filemap_dirty_folio(mapping, folio))
- return false;
- if (!fscache_cookie_valid(cookie))
- return true;
-
- if (!(inode->i_state & I_PINNING_FSCACHE_WB)) {
- spin_lock(&inode->i_lock);
- if (!(inode->i_state & I_PINNING_FSCACHE_WB)) {
- inode->i_state |= I_PINNING_FSCACHE_WB;
- need_use = true;
- }
- spin_unlock(&inode->i_lock);
-
- if (need_use)
- fscache_use_cookie(cookie, true);
- }
- return true;
-}
-EXPORT_SYMBOL(fscache_dirty_folio);
-
-struct fscache_write_request {
- struct netfs_cache_resources cache_resources;
- struct address_space *mapping;
- loff_t start;
- size_t len;
- bool set_bits;
- netfs_io_terminated_t term_func;
- void *term_func_priv;
-};
-
-void __fscache_clear_page_bits(struct address_space *mapping,
- loff_t start, size_t len)
-{
- pgoff_t first = start / PAGE_SIZE;
- pgoff_t last = (start + len - 1) / PAGE_SIZE;
- struct page *page;
-
- if (len) {
- XA_STATE(xas, &mapping->i_pages, first);
-
- rcu_read_lock();
- xas_for_each(&xas, page, last) {
- end_page_fscache(page);
- }
- rcu_read_unlock();
- }
-}
-EXPORT_SYMBOL(__fscache_clear_page_bits);
-
-/*
- * Deal with the completion of writing the data to the cache.
- */
-static void fscache_wreq_done(void *priv, ssize_t transferred_or_error,
- bool was_async)
-{
- struct fscache_write_request *wreq = priv;
-
- fscache_clear_page_bits(wreq->mapping, wreq->start, wreq->len,
- wreq->set_bits);
-
- if (wreq->term_func)
- wreq->term_func(wreq->term_func_priv, transferred_or_error,
- was_async);
- fscache_end_operation(&wreq->cache_resources);
- kfree(wreq);
-}
-
-void __fscache_write_to_cache(struct fscache_cookie *cookie,
- struct address_space *mapping,
- loff_t start, size_t len, loff_t i_size,
- netfs_io_terminated_t term_func,
- void *term_func_priv,
- bool cond)
-{
- struct fscache_write_request *wreq;
- struct netfs_cache_resources *cres;
- struct iov_iter iter;
- int ret = -ENOBUFS;
-
- if (len == 0)
- goto abandon;
-
- _enter("%llx,%zx", start, len);
-
- wreq = kzalloc(sizeof(struct fscache_write_request), GFP_NOFS);
- if (!wreq)
- goto abandon;
- wreq->mapping = mapping;
- wreq->start = start;
- wreq->len = len;
- wreq->set_bits = cond;
- wreq->term_func = term_func;
- wreq->term_func_priv = term_func_priv;
-
- cres = &wreq->cache_resources;
- if (fscache_begin_operation(cres, cookie, FSCACHE_WANT_WRITE,
- fscache_access_io_write) < 0)
- goto abandon_free;
-
- ret = cres->ops->prepare_write(cres, &start, &len, i_size, false);
- if (ret < 0)
- goto abandon_end;
-
- /* TODO: Consider clearing page bits now for space the write isn't
- * covering. This is more complicated than it appears when THPs are
- * taken into account.
- */
-
- iov_iter_xarray(&iter, ITER_SOURCE, &mapping->i_pages, start, len);
- fscache_write(cres, start, &iter, fscache_wreq_done, wreq);
- return;
-
-abandon_end:
- return fscache_wreq_done(wreq, ret, false);
-abandon_free:
- kfree(wreq);
-abandon:
- fscache_clear_page_bits(mapping, start, len, cond);
- if (term_func)
- term_func(term_func_priv, ret, false);
-}
-EXPORT_SYMBOL(__fscache_write_to_cache);
-
-/*
- * Change the size of a backing object.
- */
-void __fscache_resize_cookie(struct fscache_cookie *cookie, loff_t new_size)
-{
- struct netfs_cache_resources cres;
-
- trace_fscache_resize(cookie, new_size);
- if (fscache_begin_operation(&cres, cookie, FSCACHE_WANT_WRITE,
- fscache_access_io_resize) == 0) {
- fscache_stat(&fscache_n_resizes);
- set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &cookie->flags);
-
- /* We cannot defer a resize as we need to do it inside the
- * netfs's inode lock so that we're serialised with respect to
- * writes.
- */
- cookie->volume->cache->ops->resize_cookie(&cres, new_size);
- fscache_end_operation(&cres);
- } else {
- fscache_stat(&fscache_n_resizes_null);
- }
-}
-EXPORT_SYMBOL(__fscache_resize_cookie);