mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-23 07:26:16 +07:00
0722f18620
Use new return type vm_fault_t for fault handler in struct
vm_operations_struct. For now, this is just documenting that the
function returns a VM_FAULT value rather than an errno. Once all
instances are converted, vm_fault_t will become a distinct type.
See 1c8f422059
("mm: change return type to vm_fault_t") for reference.
Link: http://lkml.kernel.org/r/20180702152017.GA3780@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
867 lines
20 KiB
C
867 lines
20 KiB
C
/* handling of writes to regular files and writing back to the server
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*
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* Copyright (C) 2007 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 License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/backing-dev.h>
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#include <linux/slab.h>
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/writeback.h>
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#include <linux/pagevec.h>
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#include "internal.h"
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/*
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* mark a page as having been made dirty and thus needing writeback
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*/
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int afs_set_page_dirty(struct page *page)
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{
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_enter("");
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return __set_page_dirty_nobuffers(page);
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}
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/*
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* partly or wholly fill a page that's under preparation for writing
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*/
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static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
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loff_t pos, unsigned int len, struct page *page)
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{
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struct afs_read *req;
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int ret;
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_enter(",,%llu", (unsigned long long)pos);
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req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
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GFP_KERNEL);
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if (!req)
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return -ENOMEM;
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refcount_set(&req->usage, 1);
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req->pos = pos;
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req->len = len;
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req->nr_pages = 1;
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req->pages = req->array;
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req->pages[0] = page;
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get_page(page);
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ret = afs_fetch_data(vnode, key, req);
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afs_put_read(req);
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if (ret < 0) {
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if (ret == -ENOENT) {
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_debug("got NOENT from server"
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" - marking file deleted and stale");
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set_bit(AFS_VNODE_DELETED, &vnode->flags);
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ret = -ESTALE;
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}
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}
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_leave(" = %d", ret);
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return ret;
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}
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/*
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* prepare to perform part of a write to a page
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*/
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int afs_write_begin(struct file *file, struct address_space *mapping,
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loff_t pos, unsigned len, unsigned flags,
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struct page **pagep, void **fsdata)
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{
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struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
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struct page *page;
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struct key *key = afs_file_key(file);
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unsigned long priv;
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unsigned f, from = pos & (PAGE_SIZE - 1);
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unsigned t, to = from + len;
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pgoff_t index = pos >> PAGE_SHIFT;
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int ret;
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_enter("{%x:%u},{%lx},%u,%u",
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vnode->fid.vid, vnode->fid.vnode, index, from, to);
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/* We want to store information about how much of a page is altered in
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* page->private.
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*/
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BUILD_BUG_ON(PAGE_SIZE > 32768 && sizeof(page->private) < 8);
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page = grab_cache_page_write_begin(mapping, index, flags);
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if (!page)
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return -ENOMEM;
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if (!PageUptodate(page) && len != PAGE_SIZE) {
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ret = afs_fill_page(vnode, key, pos & PAGE_MASK, PAGE_SIZE, page);
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if (ret < 0) {
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unlock_page(page);
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put_page(page);
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_leave(" = %d [prep]", ret);
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return ret;
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}
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SetPageUptodate(page);
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}
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/* page won't leak in error case: it eventually gets cleaned off LRU */
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*pagep = page;
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try_again:
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/* See if this page is already partially written in a way that we can
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* merge the new write with.
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*/
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t = f = 0;
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if (PagePrivate(page)) {
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priv = page_private(page);
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f = priv & AFS_PRIV_MAX;
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t = priv >> AFS_PRIV_SHIFT;
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ASSERTCMP(f, <=, t);
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}
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if (f != t) {
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if (PageWriteback(page)) {
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trace_afs_page_dirty(vnode, tracepoint_string("alrdy"),
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page->index, priv);
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goto flush_conflicting_write;
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}
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/* If the file is being filled locally, allow inter-write
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* spaces to be merged into writes. If it's not, only write
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* back what the user gives us.
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*/
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if (!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags) &&
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(to < f || from > t))
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goto flush_conflicting_write;
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if (from < f)
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f = from;
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if (to > t)
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t = to;
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} else {
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f = from;
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t = to;
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}
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priv = (unsigned long)t << AFS_PRIV_SHIFT;
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priv |= f;
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trace_afs_page_dirty(vnode, tracepoint_string("begin"),
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page->index, priv);
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SetPagePrivate(page);
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set_page_private(page, priv);
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_leave(" = 0");
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return 0;
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/* The previous write and this write aren't adjacent or overlapping, so
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* flush the page out.
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*/
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flush_conflicting_write:
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_debug("flush conflict");
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ret = write_one_page(page);
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if (ret < 0) {
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_leave(" = %d", ret);
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return ret;
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}
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ret = lock_page_killable(page);
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if (ret < 0) {
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_leave(" = %d", ret);
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return ret;
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}
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goto try_again;
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}
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/*
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* finalise part of a write to a page
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*/
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int afs_write_end(struct file *file, struct address_space *mapping,
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loff_t pos, unsigned len, unsigned copied,
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struct page *page, void *fsdata)
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{
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struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
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struct key *key = afs_file_key(file);
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loff_t i_size, maybe_i_size;
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int ret;
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_enter("{%x:%u},{%lx}",
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vnode->fid.vid, vnode->fid.vnode, page->index);
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maybe_i_size = pos + copied;
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i_size = i_size_read(&vnode->vfs_inode);
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if (maybe_i_size > i_size) {
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spin_lock(&vnode->wb_lock);
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i_size = i_size_read(&vnode->vfs_inode);
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if (maybe_i_size > i_size)
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i_size_write(&vnode->vfs_inode, maybe_i_size);
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spin_unlock(&vnode->wb_lock);
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}
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if (!PageUptodate(page)) {
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if (copied < len) {
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/* Try and load any missing data from the server. The
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* unmarshalling routine will take care of clearing any
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* bits that are beyond the EOF.
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*/
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ret = afs_fill_page(vnode, key, pos + copied,
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len - copied, page);
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if (ret < 0)
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goto out;
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}
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SetPageUptodate(page);
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}
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set_page_dirty(page);
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if (PageDirty(page))
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_debug("dirtied");
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ret = copied;
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out:
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unlock_page(page);
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put_page(page);
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return ret;
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}
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/*
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* kill all the pages in the given range
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*/
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static void afs_kill_pages(struct address_space *mapping,
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pgoff_t first, pgoff_t last)
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{
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struct afs_vnode *vnode = AFS_FS_I(mapping->host);
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struct pagevec pv;
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unsigned count, loop;
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_enter("{%x:%u},%lx-%lx",
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vnode->fid.vid, vnode->fid.vnode, first, last);
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pagevec_init(&pv);
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do {
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_debug("kill %lx-%lx", first, last);
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count = last - first + 1;
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if (count > PAGEVEC_SIZE)
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count = PAGEVEC_SIZE;
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pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
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ASSERTCMP(pv.nr, ==, count);
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for (loop = 0; loop < count; loop++) {
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struct page *page = pv.pages[loop];
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ClearPageUptodate(page);
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SetPageError(page);
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end_page_writeback(page);
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if (page->index >= first)
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first = page->index + 1;
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lock_page(page);
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generic_error_remove_page(mapping, page);
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}
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__pagevec_release(&pv);
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} while (first <= last);
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_leave("");
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}
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/*
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* Redirty all the pages in a given range.
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*/
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static void afs_redirty_pages(struct writeback_control *wbc,
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struct address_space *mapping,
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pgoff_t first, pgoff_t last)
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{
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struct afs_vnode *vnode = AFS_FS_I(mapping->host);
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struct pagevec pv;
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unsigned count, loop;
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_enter("{%x:%u},%lx-%lx",
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vnode->fid.vid, vnode->fid.vnode, first, last);
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pagevec_init(&pv);
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do {
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_debug("redirty %lx-%lx", first, last);
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count = last - first + 1;
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if (count > PAGEVEC_SIZE)
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count = PAGEVEC_SIZE;
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pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
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ASSERTCMP(pv.nr, ==, count);
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for (loop = 0; loop < count; loop++) {
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struct page *page = pv.pages[loop];
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redirty_page_for_writepage(wbc, page);
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end_page_writeback(page);
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if (page->index >= first)
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first = page->index + 1;
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}
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__pagevec_release(&pv);
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} while (first <= last);
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_leave("");
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}
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/*
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* write to a file
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*/
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static int afs_store_data(struct address_space *mapping,
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pgoff_t first, pgoff_t last,
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unsigned offset, unsigned to)
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{
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struct afs_vnode *vnode = AFS_FS_I(mapping->host);
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struct afs_fs_cursor fc;
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struct afs_wb_key *wbk = NULL;
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struct list_head *p;
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int ret = -ENOKEY, ret2;
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_enter("%s{%x:%u.%u},%lx,%lx,%x,%x",
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vnode->volume->name,
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vnode->fid.vid,
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vnode->fid.vnode,
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vnode->fid.unique,
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first, last, offset, to);
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spin_lock(&vnode->wb_lock);
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p = vnode->wb_keys.next;
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/* Iterate through the list looking for a valid key to use. */
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try_next_key:
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while (p != &vnode->wb_keys) {
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wbk = list_entry(p, struct afs_wb_key, vnode_link);
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_debug("wbk %u", key_serial(wbk->key));
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ret2 = key_validate(wbk->key);
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if (ret2 == 0)
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goto found_key;
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if (ret == -ENOKEY)
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ret = ret2;
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p = p->next;
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|
}
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spin_unlock(&vnode->wb_lock);
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afs_put_wb_key(wbk);
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_leave(" = %d [no keys]", ret);
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return ret;
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found_key:
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refcount_inc(&wbk->usage);
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spin_unlock(&vnode->wb_lock);
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_debug("USE WB KEY %u", key_serial(wbk->key));
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ret = -ERESTARTSYS;
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if (afs_begin_vnode_operation(&fc, vnode, wbk->key)) {
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while (afs_select_fileserver(&fc)) {
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fc.cb_break = afs_calc_vnode_cb_break(vnode);
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afs_fs_store_data(&fc, mapping, first, last, offset, to);
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}
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afs_check_for_remote_deletion(&fc, fc.vnode);
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afs_vnode_commit_status(&fc, vnode, fc.cb_break);
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ret = afs_end_vnode_operation(&fc);
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}
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|
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switch (ret) {
|
|
case 0:
|
|
afs_stat_v(vnode, n_stores);
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atomic_long_add((last * PAGE_SIZE + to) -
|
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(first * PAGE_SIZE + offset),
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|
&afs_v2net(vnode)->n_store_bytes);
|
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break;
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|
case -EACCES:
|
|
case -EPERM:
|
|
case -ENOKEY:
|
|
case -EKEYEXPIRED:
|
|
case -EKEYREJECTED:
|
|
case -EKEYREVOKED:
|
|
_debug("next");
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|
spin_lock(&vnode->wb_lock);
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|
p = wbk->vnode_link.next;
|
|
afs_put_wb_key(wbk);
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|
goto try_next_key;
|
|
}
|
|
|
|
afs_put_wb_key(wbk);
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Synchronously write back the locked page and any subsequent non-locked dirty
|
|
* pages.
|
|
*/
|
|
static int afs_write_back_from_locked_page(struct address_space *mapping,
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|
struct writeback_control *wbc,
|
|
struct page *primary_page,
|
|
pgoff_t final_page)
|
|
{
|
|
struct afs_vnode *vnode = AFS_FS_I(mapping->host);
|
|
struct page *pages[8], *page;
|
|
unsigned long count, priv;
|
|
unsigned n, offset, to, f, t;
|
|
pgoff_t start, first, last;
|
|
int loop, ret;
|
|
|
|
_enter(",%lx", primary_page->index);
|
|
|
|
count = 1;
|
|
if (test_set_page_writeback(primary_page))
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|
BUG();
|
|
|
|
/* Find all consecutive lockable dirty pages that have contiguous
|
|
* written regions, stopping when we find a page that is not
|
|
* immediately lockable, is not dirty or is missing, or we reach the
|
|
* end of the range.
|
|
*/
|
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start = primary_page->index;
|
|
priv = page_private(primary_page);
|
|
offset = priv & AFS_PRIV_MAX;
|
|
to = priv >> AFS_PRIV_SHIFT;
|
|
trace_afs_page_dirty(vnode, tracepoint_string("store"),
|
|
primary_page->index, priv);
|
|
|
|
WARN_ON(offset == to);
|
|
if (offset == to)
|
|
trace_afs_page_dirty(vnode, tracepoint_string("WARN"),
|
|
primary_page->index, priv);
|
|
|
|
if (start >= final_page ||
|
|
(to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)))
|
|
goto no_more;
|
|
|
|
start++;
|
|
do {
|
|
_debug("more %lx [%lx]", start, count);
|
|
n = final_page - start + 1;
|
|
if (n > ARRAY_SIZE(pages))
|
|
n = ARRAY_SIZE(pages);
|
|
n = find_get_pages_contig(mapping, start, ARRAY_SIZE(pages), pages);
|
|
_debug("fgpc %u", n);
|
|
if (n == 0)
|
|
goto no_more;
|
|
if (pages[0]->index != start) {
|
|
do {
|
|
put_page(pages[--n]);
|
|
} while (n > 0);
|
|
goto no_more;
|
|
}
|
|
|
|
for (loop = 0; loop < n; loop++) {
|
|
page = pages[loop];
|
|
if (to != PAGE_SIZE &&
|
|
!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))
|
|
break;
|
|
if (page->index > final_page)
|
|
break;
|
|
if (!trylock_page(page))
|
|
break;
|
|
if (!PageDirty(page) || PageWriteback(page)) {
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
|
|
priv = page_private(page);
|
|
f = priv & AFS_PRIV_MAX;
|
|
t = priv >> AFS_PRIV_SHIFT;
|
|
if (f != 0 &&
|
|
!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) {
|
|
unlock_page(page);
|
|
break;
|
|
}
|
|
to = t;
|
|
|
|
trace_afs_page_dirty(vnode, tracepoint_string("store+"),
|
|
page->index, priv);
|
|
|
|
if (!clear_page_dirty_for_io(page))
|
|
BUG();
|
|
if (test_set_page_writeback(page))
|
|
BUG();
|
|
unlock_page(page);
|
|
put_page(page);
|
|
}
|
|
count += loop;
|
|
if (loop < n) {
|
|
for (; loop < n; loop++)
|
|
put_page(pages[loop]);
|
|
goto no_more;
|
|
}
|
|
|
|
start += loop;
|
|
} while (start <= final_page && count < 65536);
|
|
|
|
no_more:
|
|
/* We now have a contiguous set of dirty pages, each with writeback
|
|
* set; the first page is still locked at this point, but all the rest
|
|
* have been unlocked.
|
|
*/
|
|
unlock_page(primary_page);
|
|
|
|
first = primary_page->index;
|
|
last = first + count - 1;
|
|
|
|
_debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to);
|
|
|
|
ret = afs_store_data(mapping, first, last, offset, to);
|
|
switch (ret) {
|
|
case 0:
|
|
ret = count;
|
|
break;
|
|
|
|
default:
|
|
pr_notice("kAFS: Unexpected error from FS.StoreData %d\n", ret);
|
|
/* Fall through */
|
|
case -EACCES:
|
|
case -EPERM:
|
|
case -ENOKEY:
|
|
case -EKEYEXPIRED:
|
|
case -EKEYREJECTED:
|
|
case -EKEYREVOKED:
|
|
afs_redirty_pages(wbc, mapping, first, last);
|
|
mapping_set_error(mapping, ret);
|
|
break;
|
|
|
|
case -EDQUOT:
|
|
case -ENOSPC:
|
|
afs_redirty_pages(wbc, mapping, first, last);
|
|
mapping_set_error(mapping, -ENOSPC);
|
|
break;
|
|
|
|
case -EROFS:
|
|
case -EIO:
|
|
case -EREMOTEIO:
|
|
case -EFBIG:
|
|
case -ENOENT:
|
|
case -ENOMEDIUM:
|
|
case -ENXIO:
|
|
afs_kill_pages(mapping, first, last);
|
|
mapping_set_error(mapping, ret);
|
|
break;
|
|
}
|
|
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* write a page back to the server
|
|
* - the caller locked the page for us
|
|
*/
|
|
int afs_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int ret;
|
|
|
|
_enter("{%lx},", page->index);
|
|
|
|
ret = afs_write_back_from_locked_page(page->mapping, wbc, page,
|
|
wbc->range_end >> PAGE_SHIFT);
|
|
if (ret < 0) {
|
|
_leave(" = %d", ret);
|
|
return 0;
|
|
}
|
|
|
|
wbc->nr_to_write -= ret;
|
|
|
|
_leave(" = 0");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* write a region of pages back to the server
|
|
*/
|
|
static int afs_writepages_region(struct address_space *mapping,
|
|
struct writeback_control *wbc,
|
|
pgoff_t index, pgoff_t end, pgoff_t *_next)
|
|
{
|
|
struct page *page;
|
|
int ret, n;
|
|
|
|
_enter(",,%lx,%lx,", index, end);
|
|
|
|
do {
|
|
n = find_get_pages_range_tag(mapping, &index, end,
|
|
PAGECACHE_TAG_DIRTY, 1, &page);
|
|
if (!n)
|
|
break;
|
|
|
|
_debug("wback %lx", page->index);
|
|
|
|
/*
|
|
* at this point we hold neither the i_pages lock nor the
|
|
* page lock: the page may be truncated or invalidated
|
|
* (changing page->mapping to NULL), or even swizzled
|
|
* back from swapper_space to tmpfs file mapping
|
|
*/
|
|
ret = lock_page_killable(page);
|
|
if (ret < 0) {
|
|
put_page(page);
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
if (page->mapping != mapping || !PageDirty(page)) {
|
|
unlock_page(page);
|
|
put_page(page);
|
|
continue;
|
|
}
|
|
|
|
if (PageWriteback(page)) {
|
|
unlock_page(page);
|
|
if (wbc->sync_mode != WB_SYNC_NONE)
|
|
wait_on_page_writeback(page);
|
|
put_page(page);
|
|
continue;
|
|
}
|
|
|
|
if (!clear_page_dirty_for_io(page))
|
|
BUG();
|
|
ret = afs_write_back_from_locked_page(mapping, wbc, page, end);
|
|
put_page(page);
|
|
if (ret < 0) {
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
wbc->nr_to_write -= ret;
|
|
|
|
cond_resched();
|
|
} while (index < end && wbc->nr_to_write > 0);
|
|
|
|
*_next = index;
|
|
_leave(" = 0 [%lx]", *_next);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* write some of the pending data back to the server
|
|
*/
|
|
int afs_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
pgoff_t start, end, next;
|
|
int ret;
|
|
|
|
_enter("");
|
|
|
|
if (wbc->range_cyclic) {
|
|
start = mapping->writeback_index;
|
|
end = -1;
|
|
ret = afs_writepages_region(mapping, wbc, start, end, &next);
|
|
if (start > 0 && wbc->nr_to_write > 0 && ret == 0)
|
|
ret = afs_writepages_region(mapping, wbc, 0, start,
|
|
&next);
|
|
mapping->writeback_index = next;
|
|
} else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
|
|
end = (pgoff_t)(LLONG_MAX >> PAGE_SHIFT);
|
|
ret = afs_writepages_region(mapping, wbc, 0, end, &next);
|
|
if (wbc->nr_to_write > 0)
|
|
mapping->writeback_index = next;
|
|
} else {
|
|
start = wbc->range_start >> PAGE_SHIFT;
|
|
end = wbc->range_end >> PAGE_SHIFT;
|
|
ret = afs_writepages_region(mapping, wbc, start, end, &next);
|
|
}
|
|
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* completion of write to server
|
|
*/
|
|
void afs_pages_written_back(struct afs_vnode *vnode, struct afs_call *call)
|
|
{
|
|
struct pagevec pv;
|
|
unsigned long priv;
|
|
unsigned count, loop;
|
|
pgoff_t first = call->first, last = call->last;
|
|
|
|
_enter("{%x:%u},{%lx-%lx}",
|
|
vnode->fid.vid, vnode->fid.vnode, first, last);
|
|
|
|
pagevec_init(&pv);
|
|
|
|
do {
|
|
_debug("done %lx-%lx", first, last);
|
|
|
|
count = last - first + 1;
|
|
if (count > PAGEVEC_SIZE)
|
|
count = PAGEVEC_SIZE;
|
|
pv.nr = find_get_pages_contig(vnode->vfs_inode.i_mapping,
|
|
first, count, pv.pages);
|
|
ASSERTCMP(pv.nr, ==, count);
|
|
|
|
for (loop = 0; loop < count; loop++) {
|
|
priv = page_private(pv.pages[loop]);
|
|
trace_afs_page_dirty(vnode, tracepoint_string("clear"),
|
|
pv.pages[loop]->index, priv);
|
|
set_page_private(pv.pages[loop], 0);
|
|
end_page_writeback(pv.pages[loop]);
|
|
}
|
|
first += count;
|
|
__pagevec_release(&pv);
|
|
} while (first <= last);
|
|
|
|
afs_prune_wb_keys(vnode);
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* write to an AFS file
|
|
*/
|
|
ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp));
|
|
ssize_t result;
|
|
size_t count = iov_iter_count(from);
|
|
|
|
_enter("{%x.%u},{%zu},",
|
|
vnode->fid.vid, vnode->fid.vnode, count);
|
|
|
|
if (IS_SWAPFILE(&vnode->vfs_inode)) {
|
|
printk(KERN_INFO
|
|
"AFS: Attempt to write to active swap file!\n");
|
|
return -EBUSY;
|
|
}
|
|
|
|
if (!count)
|
|
return 0;
|
|
|
|
result = generic_file_write_iter(iocb, from);
|
|
|
|
_leave(" = %zd", result);
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* flush any dirty pages for this process, and check for write errors.
|
|
* - the return status from this call provides a reliable indication of
|
|
* whether any write errors occurred for this process.
|
|
*/
|
|
int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
struct inode *inode = file_inode(file);
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
|
|
_enter("{%x:%u},{n=%pD},%d",
|
|
vnode->fid.vid, vnode->fid.vnode, file,
|
|
datasync);
|
|
|
|
return file_write_and_wait_range(file, start, end);
|
|
}
|
|
|
|
/*
|
|
* notification that a previously read-only page is about to become writable
|
|
* - if it returns an error, the caller will deliver a bus error signal
|
|
*/
|
|
vm_fault_t afs_page_mkwrite(struct vm_fault *vmf)
|
|
{
|
|
struct file *file = vmf->vma->vm_file;
|
|
struct inode *inode = file_inode(file);
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
unsigned long priv;
|
|
|
|
_enter("{{%x:%u}},{%lx}",
|
|
vnode->fid.vid, vnode->fid.vnode, vmf->page->index);
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
|
|
/* Wait for the page to be written to the cache before we allow it to
|
|
* be modified. We then assume the entire page will need writing back.
|
|
*/
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
fscache_wait_on_page_write(vnode->cache, vmf->page);
|
|
#endif
|
|
|
|
if (PageWriteback(vmf->page) &&
|
|
wait_on_page_bit_killable(vmf->page, PG_writeback) < 0)
|
|
return VM_FAULT_RETRY;
|
|
|
|
if (lock_page_killable(vmf->page) < 0)
|
|
return VM_FAULT_RETRY;
|
|
|
|
/* We mustn't change page->private until writeback is complete as that
|
|
* details the portion of the page we need to write back and we might
|
|
* need to redirty the page if there's a problem.
|
|
*/
|
|
wait_on_page_writeback(vmf->page);
|
|
|
|
priv = (unsigned long)PAGE_SIZE << AFS_PRIV_SHIFT; /* To */
|
|
priv |= 0; /* From */
|
|
trace_afs_page_dirty(vnode, tracepoint_string("mkwrite"),
|
|
vmf->page->index, priv);
|
|
SetPagePrivate(vmf->page);
|
|
set_page_private(vmf->page, priv);
|
|
|
|
sb_end_pagefault(inode->i_sb);
|
|
return VM_FAULT_LOCKED;
|
|
}
|
|
|
|
/*
|
|
* Prune the keys cached for writeback. The caller must hold vnode->wb_lock.
|
|
*/
|
|
void afs_prune_wb_keys(struct afs_vnode *vnode)
|
|
{
|
|
LIST_HEAD(graveyard);
|
|
struct afs_wb_key *wbk, *tmp;
|
|
|
|
/* Discard unused keys */
|
|
spin_lock(&vnode->wb_lock);
|
|
|
|
if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) &&
|
|
!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) {
|
|
list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) {
|
|
if (refcount_read(&wbk->usage) == 1)
|
|
list_move(&wbk->vnode_link, &graveyard);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&vnode->wb_lock);
|
|
|
|
while (!list_empty(&graveyard)) {
|
|
wbk = list_entry(graveyard.next, struct afs_wb_key, vnode_link);
|
|
list_del(&wbk->vnode_link);
|
|
afs_put_wb_key(wbk);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Clean up a page during invalidation.
|
|
*/
|
|
int afs_launder_page(struct page *page)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct afs_vnode *vnode = AFS_FS_I(mapping->host);
|
|
unsigned long priv;
|
|
unsigned int f, t;
|
|
int ret = 0;
|
|
|
|
_enter("{%lx}", page->index);
|
|
|
|
priv = page_private(page);
|
|
if (clear_page_dirty_for_io(page)) {
|
|
f = 0;
|
|
t = PAGE_SIZE;
|
|
if (PagePrivate(page)) {
|
|
f = priv & AFS_PRIV_MAX;
|
|
t = priv >> AFS_PRIV_SHIFT;
|
|
}
|
|
|
|
trace_afs_page_dirty(vnode, tracepoint_string("launder"),
|
|
page->index, priv);
|
|
ret = afs_store_data(mapping, page->index, page->index, t, f);
|
|
}
|
|
|
|
trace_afs_page_dirty(vnode, tracepoint_string("laundered"),
|
|
page->index, priv);
|
|
set_page_private(page, 0);
|
|
ClearPagePrivate(page);
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
if (PageFsCache(page)) {
|
|
fscache_wait_on_page_write(vnode->cache, page);
|
|
fscache_uncache_page(vnode->cache, page);
|
|
}
|
|
#endif
|
|
return ret;
|
|
}
|