mirror of
https://github.com/edk2-porting/linux-next.git
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201a15428b
Handle netfs pages that the vmscan algorithm wants to evict from the pagecache under OOM conditions, but that are waiting for write to the cache. Under these conditions, vmscan calls the releasepage() function of the netfs, asking if a page can be discarded. The problem is typified by the following trace of a stuck process: kslowd005 D 0000000000000000 0 4253 2 0x00000080 ffff88001b14f370 0000000000000046 ffff880020d0d000 0000000000000007 0000000000000006 0000000000000001 ffff88001b14ffd8 ffff880020d0d2a8 000000000000ddf0 00000000000118c0 00000000000118c0 ffff880020d0d2a8 Call Trace: [<ffffffffa00782d8>] __fscache_wait_on_page_write+0x8b/0xa7 [fscache] [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffffa0078240>] ? __fscache_check_page_write+0x63/0x70 [fscache] [<ffffffffa00b671d>] nfs_fscache_release_page+0x4e/0xc4 [nfs] [<ffffffffa00927f0>] nfs_release_page+0x3c/0x41 [nfs] [<ffffffff810885d3>] try_to_release_page+0x32/0x3b [<ffffffff81093203>] shrink_page_list+0x316/0x4ac [<ffffffff8109372b>] shrink_inactive_list+0x392/0x67c [<ffffffff813532fa>] ? __mutex_unlock_slowpath+0x100/0x10b [<ffffffff81058df0>] ? trace_hardirqs_on_caller+0x10c/0x130 [<ffffffff8135330e>] ? mutex_unlock+0x9/0xb [<ffffffff81093aa2>] shrink_list+0x8d/0x8f [<ffffffff81093d1c>] shrink_zone+0x278/0x33c [<ffffffff81052d6c>] ? ktime_get_ts+0xad/0xba [<ffffffff81094b13>] try_to_free_pages+0x22e/0x392 [<ffffffff81091e24>] ? isolate_pages_global+0x0/0x212 [<ffffffff8108e743>] __alloc_pages_nodemask+0x3dc/0x5cf [<ffffffff81089529>] grab_cache_page_write_begin+0x65/0xaa [<ffffffff8110f8c0>] ext3_write_begin+0x78/0x1eb [<ffffffff81089ec5>] generic_file_buffered_write+0x109/0x28c [<ffffffff8103cb69>] ? current_fs_time+0x22/0x29 [<ffffffff8108a509>] __generic_file_aio_write+0x350/0x385 [<ffffffff8108a588>] ? generic_file_aio_write+0x4a/0xae [<ffffffff8108a59e>] generic_file_aio_write+0x60/0xae [<ffffffff810b2e82>] do_sync_write+0xe3/0x120 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff810b18e1>] ? __dentry_open+0x1a5/0x2b8 [<ffffffff810b1a76>] ? dentry_open+0x82/0x89 [<ffffffffa00e693c>] cachefiles_write_page+0x298/0x335 [cachefiles] [<ffffffffa0077147>] fscache_write_op+0x178/0x2c2 [fscache] [<ffffffffa0075656>] fscache_op_execute+0x7a/0xd1 [fscache] [<ffffffff81082093>] slow_work_execute+0x18f/0x2d1 [<ffffffff8108239a>] slow_work_thread+0x1c5/0x308 [<ffffffff8104c0f1>] ? autoremove_wake_function+0x0/0x34 [<ffffffff810821d5>] ? slow_work_thread+0x0/0x308 [<ffffffff8104be91>] kthread+0x7a/0x82 [<ffffffff8100beda>] child_rip+0xa/0x20 [<ffffffff8100b87c>] ? restore_args+0x0/0x30 [<ffffffff8102ef83>] ? tg_shares_up+0x171/0x227 [<ffffffff8104be17>] ? kthread+0x0/0x82 [<ffffffff8100bed0>] ? child_rip+0x0/0x20 In the above backtrace, the following is happening: (1) A page storage operation is being executed by a slow-work thread (fscache_write_op()). (2) FS-Cache farms the operation out to the cache to perform (cachefiles_write_page()). (3) CacheFiles is then calling Ext3 to perform the actual write, using Ext3's standard write (do_sync_write()) under KERNEL_DS directly from the netfs page. (4) However, for Ext3 to perform the write, it must allocate some memory, in particular, it must allocate at least one page cache page into which it can copy the data from the netfs page. (5) Under OOM conditions, the memory allocator can't immediately come up with a page, so it uses vmscan to find something to discard (try_to_free_pages()). (6) vmscan finds a clean netfs page it might be able to discard (possibly the one it's trying to write out). (7) The netfs is called to throw the page away (nfs_release_page()) - but it's called with __GFP_WAIT, so the netfs decides to wait for the store to complete (__fscache_wait_on_page_write()). (8) This blocks a slow-work processing thread - possibly against itself. The system ends up stuck because it can't write out any netfs pages to the cache without allocating more memory. To avoid this, we make FS-Cache cancel some writes that aren't in the middle of actually being performed. This means that some data won't make it into the cache this time. To support this, a new FS-Cache function is added fscache_maybe_release_page() that replaces what the netfs releasepage() functions used to do with respect to the cache. The decisions fscache_maybe_release_page() makes are counted and displayed through /proc/fs/fscache/stats on a line labelled "VmScan". There are four counters provided: "nos=N" - pages that weren't pending storage; "gon=N" - pages that were pending storage when we first looked, but weren't by the time we got the object lock; "bsy=N" - pages that we ignored as they were actively being written when we looked; and "can=N" - pages that we cancelled the storage of. What I'd really like to do is alter the behaviour of the cancellation heuristics, depending on how necessary it is to expel pages. If there are plenty of other pages that aren't waiting to be written to the cache that could be ejected first, then it would be nice to hold up on immediate cancellation of cache writes - but I don't see a way of doing that. Signed-off-by: David Howells <dhowells@redhat.com>
537 lines
14 KiB
C
537 lines
14 KiB
C
/* NFS filesystem cache interface
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*
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* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/nfs_fs.h>
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#include <linux/nfs_fs_sb.h>
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#include <linux/in6.h>
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#include <linux/seq_file.h>
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#include "internal.h"
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#include "iostat.h"
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#include "fscache.h"
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#define NFSDBG_FACILITY NFSDBG_FSCACHE
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static struct rb_root nfs_fscache_keys = RB_ROOT;
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static DEFINE_SPINLOCK(nfs_fscache_keys_lock);
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/*
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* Get the per-client index cookie for an NFS client if the appropriate mount
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* flag was set
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* - We always try and get an index cookie for the client, but get filehandle
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* cookies on a per-superblock basis, depending on the mount flags
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*/
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void nfs_fscache_get_client_cookie(struct nfs_client *clp)
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{
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/* create a cache index for looking up filehandles */
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clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
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&nfs_fscache_server_index_def,
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clp);
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dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
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clp, clp->fscache);
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}
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/*
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* Dispose of a per-client cookie
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*/
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void nfs_fscache_release_client_cookie(struct nfs_client *clp)
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{
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dfprintk(FSCACHE, "NFS: releasing client cookie (0x%p/0x%p)\n",
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clp, clp->fscache);
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fscache_relinquish_cookie(clp->fscache, 0);
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clp->fscache = NULL;
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}
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/*
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* Get the cache cookie for an NFS superblock. We have to handle
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* uniquification here because the cache doesn't do it for us.
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*
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* The default uniquifier is just an empty string, but it may be overridden
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* either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
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* superblock across an automount point of some nature.
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*/
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void nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq,
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struct nfs_clone_mount *mntdata)
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{
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struct nfs_fscache_key *key, *xkey;
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struct nfs_server *nfss = NFS_SB(sb);
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struct rb_node **p, *parent;
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int diff, ulen;
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if (uniq) {
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ulen = strlen(uniq);
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} else if (mntdata) {
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struct nfs_server *mnt_s = NFS_SB(mntdata->sb);
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if (mnt_s->fscache_key) {
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uniq = mnt_s->fscache_key->key.uniquifier;
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ulen = mnt_s->fscache_key->key.uniq_len;
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}
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}
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if (!uniq) {
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uniq = "";
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ulen = 1;
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}
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key = kzalloc(sizeof(*key) + ulen, GFP_KERNEL);
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if (!key)
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return;
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key->nfs_client = nfss->nfs_client;
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key->key.super.s_flags = sb->s_flags & NFS_MS_MASK;
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key->key.nfs_server.flags = nfss->flags;
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key->key.nfs_server.rsize = nfss->rsize;
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key->key.nfs_server.wsize = nfss->wsize;
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key->key.nfs_server.acregmin = nfss->acregmin;
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key->key.nfs_server.acregmax = nfss->acregmax;
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key->key.nfs_server.acdirmin = nfss->acdirmin;
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key->key.nfs_server.acdirmax = nfss->acdirmax;
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key->key.nfs_server.fsid = nfss->fsid;
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key->key.rpc_auth.au_flavor = nfss->client->cl_auth->au_flavor;
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key->key.uniq_len = ulen;
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memcpy(key->key.uniquifier, uniq, ulen);
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spin_lock(&nfs_fscache_keys_lock);
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p = &nfs_fscache_keys.rb_node;
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parent = NULL;
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while (*p) {
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parent = *p;
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xkey = rb_entry(parent, struct nfs_fscache_key, node);
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if (key->nfs_client < xkey->nfs_client)
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goto go_left;
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if (key->nfs_client > xkey->nfs_client)
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goto go_right;
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diff = memcmp(&key->key, &xkey->key, sizeof(key->key));
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if (diff < 0)
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goto go_left;
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if (diff > 0)
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goto go_right;
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if (key->key.uniq_len == 0)
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goto non_unique;
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diff = memcmp(key->key.uniquifier,
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xkey->key.uniquifier,
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key->key.uniq_len);
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if (diff < 0)
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goto go_left;
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if (diff > 0)
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goto go_right;
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goto non_unique;
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go_left:
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p = &(*p)->rb_left;
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continue;
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go_right:
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p = &(*p)->rb_right;
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}
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rb_link_node(&key->node, parent, p);
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rb_insert_color(&key->node, &nfs_fscache_keys);
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spin_unlock(&nfs_fscache_keys_lock);
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nfss->fscache_key = key;
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/* create a cache index for looking up filehandles */
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nfss->fscache = fscache_acquire_cookie(nfss->nfs_client->fscache,
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&nfs_fscache_super_index_def,
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nfss);
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dfprintk(FSCACHE, "NFS: get superblock cookie (0x%p/0x%p)\n",
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nfss, nfss->fscache);
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return;
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non_unique:
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spin_unlock(&nfs_fscache_keys_lock);
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kfree(key);
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nfss->fscache_key = NULL;
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nfss->fscache = NULL;
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printk(KERN_WARNING "NFS:"
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" Cache request denied due to non-unique superblock keys\n");
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}
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/*
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* release a per-superblock cookie
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*/
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void nfs_fscache_release_super_cookie(struct super_block *sb)
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{
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struct nfs_server *nfss = NFS_SB(sb);
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dfprintk(FSCACHE, "NFS: releasing superblock cookie (0x%p/0x%p)\n",
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nfss, nfss->fscache);
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fscache_relinquish_cookie(nfss->fscache, 0);
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nfss->fscache = NULL;
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if (nfss->fscache_key) {
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spin_lock(&nfs_fscache_keys_lock);
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rb_erase(&nfss->fscache_key->node, &nfs_fscache_keys);
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spin_unlock(&nfs_fscache_keys_lock);
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kfree(nfss->fscache_key);
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nfss->fscache_key = NULL;
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}
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}
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/*
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* Initialise the per-inode cache cookie pointer for an NFS inode.
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*/
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void nfs_fscache_init_inode_cookie(struct inode *inode)
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{
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NFS_I(inode)->fscache = NULL;
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if (S_ISREG(inode->i_mode))
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set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
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}
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/*
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* Get the per-inode cache cookie for an NFS inode.
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*/
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static void nfs_fscache_enable_inode_cookie(struct inode *inode)
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{
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struct super_block *sb = inode->i_sb;
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struct nfs_inode *nfsi = NFS_I(inode);
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if (nfsi->fscache || !NFS_FSCACHE(inode))
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return;
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if ((NFS_SB(sb)->options & NFS_OPTION_FSCACHE)) {
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nfsi->fscache = fscache_acquire_cookie(
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NFS_SB(sb)->fscache,
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&nfs_fscache_inode_object_def,
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nfsi);
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dfprintk(FSCACHE, "NFS: get FH cookie (0x%p/0x%p/0x%p)\n",
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sb, nfsi, nfsi->fscache);
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}
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}
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/*
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* Release a per-inode cookie.
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*/
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void nfs_fscache_release_inode_cookie(struct inode *inode)
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{
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struct nfs_inode *nfsi = NFS_I(inode);
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dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n",
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nfsi, nfsi->fscache);
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fscache_relinquish_cookie(nfsi->fscache, 0);
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nfsi->fscache = NULL;
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}
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/*
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* Retire a per-inode cookie, destroying the data attached to it.
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*/
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void nfs_fscache_zap_inode_cookie(struct inode *inode)
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{
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struct nfs_inode *nfsi = NFS_I(inode);
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dfprintk(FSCACHE, "NFS: zapping cookie (0x%p/0x%p)\n",
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nfsi, nfsi->fscache);
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fscache_relinquish_cookie(nfsi->fscache, 1);
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nfsi->fscache = NULL;
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}
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/*
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* Turn off the cache with regard to a per-inode cookie if opened for writing,
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* invalidating all the pages in the page cache relating to the associated
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* inode to clear the per-page caching.
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*/
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static void nfs_fscache_disable_inode_cookie(struct inode *inode)
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{
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clear_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
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if (NFS_I(inode)->fscache) {
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dfprintk(FSCACHE,
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"NFS: nfsi 0x%p turning cache off\n", NFS_I(inode));
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/* Need to invalidate any mapped pages that were read in before
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* turning off the cache.
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*/
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if (inode->i_mapping && inode->i_mapping->nrpages)
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invalidate_inode_pages2(inode->i_mapping);
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nfs_fscache_zap_inode_cookie(inode);
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}
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}
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/*
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* wait_on_bit() sleep function for uninterruptible waiting
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*/
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static int nfs_fscache_wait_bit(void *flags)
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{
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schedule();
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return 0;
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}
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/*
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* Lock against someone else trying to also acquire or relinquish a cookie
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*/
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static inline void nfs_fscache_inode_lock(struct inode *inode)
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{
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struct nfs_inode *nfsi = NFS_I(inode);
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while (test_and_set_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags))
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wait_on_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK,
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nfs_fscache_wait_bit, TASK_UNINTERRUPTIBLE);
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}
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/*
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* Unlock cookie management lock
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*/
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static inline void nfs_fscache_inode_unlock(struct inode *inode)
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{
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struct nfs_inode *nfsi = NFS_I(inode);
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smp_mb__before_clear_bit();
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clear_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags);
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smp_mb__after_clear_bit();
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wake_up_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK);
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}
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/*
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* Decide if we should enable or disable local caching for this inode.
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* - For now, with NFS, only regular files that are open read-only will be able
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* to use the cache.
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* - May be invoked multiple times in parallel by parallel nfs_open() functions.
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*/
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void nfs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
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{
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if (NFS_FSCACHE(inode)) {
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nfs_fscache_inode_lock(inode);
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if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
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nfs_fscache_disable_inode_cookie(inode);
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else
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nfs_fscache_enable_inode_cookie(inode);
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nfs_fscache_inode_unlock(inode);
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}
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}
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/*
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* Replace a per-inode cookie due to revalidation detecting a file having
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* changed on the server.
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*/
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void nfs_fscache_reset_inode_cookie(struct inode *inode)
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{
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struct nfs_inode *nfsi = NFS_I(inode);
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struct nfs_server *nfss = NFS_SERVER(inode);
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struct fscache_cookie *old = nfsi->fscache;
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nfs_fscache_inode_lock(inode);
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if (nfsi->fscache) {
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/* retire the current fscache cache and get a new one */
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fscache_relinquish_cookie(nfsi->fscache, 1);
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nfsi->fscache = fscache_acquire_cookie(
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nfss->nfs_client->fscache,
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&nfs_fscache_inode_object_def,
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nfsi);
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dfprintk(FSCACHE,
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"NFS: revalidation new cookie (0x%p/0x%p/0x%p/0x%p)\n",
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nfss, nfsi, old, nfsi->fscache);
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}
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nfs_fscache_inode_unlock(inode);
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}
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/*
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* Release the caching state associated with a page, if the page isn't busy
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* interacting with the cache.
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* - Returns true (can release page) or false (page busy).
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*/
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int nfs_fscache_release_page(struct page *page, gfp_t gfp)
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{
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struct nfs_inode *nfsi = NFS_I(page->mapping->host);
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struct fscache_cookie *cookie = nfsi->fscache;
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BUG_ON(!cookie);
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if (PageFsCache(page)) {
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dfprintk(FSCACHE, "NFS: fscache releasepage (0x%p/0x%p/0x%p)\n",
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cookie, page, nfsi);
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if (!fscache_maybe_release_page(cookie, page, gfp))
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return 0;
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nfs_add_fscache_stats(page->mapping->host,
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NFSIOS_FSCACHE_PAGES_UNCACHED, 1);
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}
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return 1;
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|
}
|
|
|
|
/*
|
|
* Release the caching state associated with a page if undergoing complete page
|
|
* invalidation.
|
|
*/
|
|
void __nfs_fscache_invalidate_page(struct page *page, struct inode *inode)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct fscache_cookie *cookie = nfsi->fscache;
|
|
|
|
BUG_ON(!cookie);
|
|
|
|
dfprintk(FSCACHE, "NFS: fscache invalidatepage (0x%p/0x%p/0x%p)\n",
|
|
cookie, page, nfsi);
|
|
|
|
fscache_wait_on_page_write(cookie, page);
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
fscache_uncache_page(cookie, page);
|
|
nfs_add_fscache_stats(page->mapping->host,
|
|
NFSIOS_FSCACHE_PAGES_UNCACHED, 1);
|
|
}
|
|
|
|
/*
|
|
* Handle completion of a page being read from the cache.
|
|
* - Called in process (keventd) context.
|
|
*/
|
|
static void nfs_readpage_from_fscache_complete(struct page *page,
|
|
void *context,
|
|
int error)
|
|
{
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_from_fscache_complete (0x%p/0x%p/%d)\n",
|
|
page, context, error);
|
|
|
|
/* if the read completes with an error, we just unlock the page and let
|
|
* the VM reissue the readpage */
|
|
if (!error) {
|
|
SetPageUptodate(page);
|
|
unlock_page(page);
|
|
} else {
|
|
error = nfs_readpage_async(context, page->mapping->host, page);
|
|
if (error)
|
|
unlock_page(page);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Retrieve a page from fscache
|
|
*/
|
|
int __nfs_readpage_from_fscache(struct nfs_open_context *ctx,
|
|
struct inode *inode, struct page *page)
|
|
{
|
|
int ret;
|
|
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_from_fscache(fsc:%p/p:%p(i:%lx f:%lx)/0x%p)\n",
|
|
NFS_I(inode)->fscache, page, page->index, page->flags, inode);
|
|
|
|
ret = fscache_read_or_alloc_page(NFS_I(inode)->fscache,
|
|
page,
|
|
nfs_readpage_from_fscache_complete,
|
|
ctx,
|
|
GFP_KERNEL);
|
|
|
|
switch (ret) {
|
|
case 0: /* read BIO submitted (page in fscache) */
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_from_fscache: BIO submitted\n");
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_OK, 1);
|
|
return ret;
|
|
|
|
case -ENOBUFS: /* inode not in cache */
|
|
case -ENODATA: /* page not in cache */
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL, 1);
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_from_fscache %d\n", ret);
|
|
return 1;
|
|
|
|
default:
|
|
dfprintk(FSCACHE, "NFS: readpage_from_fscache %d\n", ret);
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL, 1);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Retrieve a set of pages from fscache
|
|
*/
|
|
int __nfs_readpages_from_fscache(struct nfs_open_context *ctx,
|
|
struct inode *inode,
|
|
struct address_space *mapping,
|
|
struct list_head *pages,
|
|
unsigned *nr_pages)
|
|
{
|
|
int ret, npages = *nr_pages;
|
|
|
|
dfprintk(FSCACHE, "NFS: nfs_getpages_from_fscache (0x%p/%u/0x%p)\n",
|
|
NFS_I(inode)->fscache, npages, inode);
|
|
|
|
ret = fscache_read_or_alloc_pages(NFS_I(inode)->fscache,
|
|
mapping, pages, nr_pages,
|
|
nfs_readpage_from_fscache_complete,
|
|
ctx,
|
|
mapping_gfp_mask(mapping));
|
|
if (*nr_pages < npages)
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_OK,
|
|
npages);
|
|
if (*nr_pages > 0)
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_READ_FAIL,
|
|
*nr_pages);
|
|
|
|
switch (ret) {
|
|
case 0: /* read submitted to the cache for all pages */
|
|
BUG_ON(!list_empty(pages));
|
|
BUG_ON(*nr_pages != 0);
|
|
dfprintk(FSCACHE,
|
|
"NFS: nfs_getpages_from_fscache: submitted\n");
|
|
|
|
return ret;
|
|
|
|
case -ENOBUFS: /* some pages aren't cached and can't be */
|
|
case -ENODATA: /* some pages aren't cached */
|
|
dfprintk(FSCACHE,
|
|
"NFS: nfs_getpages_from_fscache: no page: %d\n", ret);
|
|
return 1;
|
|
|
|
default:
|
|
dfprintk(FSCACHE,
|
|
"NFS: nfs_getpages_from_fscache: ret %d\n", ret);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Store a newly fetched page in fscache
|
|
* - PG_fscache must be set on the page
|
|
*/
|
|
void __nfs_readpage_to_fscache(struct inode *inode, struct page *page, int sync)
|
|
{
|
|
int ret;
|
|
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_to_fscache(fsc:%p/p:%p(i:%lx f:%lx)/%d)\n",
|
|
NFS_I(inode)->fscache, page, page->index, page->flags, sync);
|
|
|
|
ret = fscache_write_page(NFS_I(inode)->fscache, page, GFP_KERNEL);
|
|
dfprintk(FSCACHE,
|
|
"NFS: readpage_to_fscache: p:%p(i:%lu f:%lx) ret %d\n",
|
|
page, page->index, page->flags, ret);
|
|
|
|
if (ret != 0) {
|
|
fscache_uncache_page(NFS_I(inode)->fscache, page);
|
|
nfs_add_fscache_stats(inode,
|
|
NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL, 1);
|
|
nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_UNCACHED, 1);
|
|
} else {
|
|
nfs_add_fscache_stats(inode,
|
|
NFSIOS_FSCACHE_PAGES_WRITTEN_OK, 1);
|
|
}
|
|
}
|