mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 11:56:40 +07:00
d47992f86b
Currently there is no way to truncate partial page where the end truncate point is not at the end of the page. This is because it was not needed and the functionality was enough for file system truncate operation to work properly. However more file systems now support punch hole feature and it can benefit from mm supporting truncating page just up to the certain point. Specifically, with this functionality truncate_inode_pages_range() can be changed so it supports truncating partial page at the end of the range (currently it will BUG_ON() if 'end' is not at the end of the page). This commit changes the invalidatepage() address space operation prototype to accept range to be invalidated and update all the instances for it. We also change the block_invalidatepage() in the same way and actually make a use of the new length argument implementing range invalidation. Actual file system implementations will follow except the file systems where the changes are really simple and should not change the behaviour in any way .Implementation for truncate_page_range() which will be able to accept page unaligned ranges will follow as well. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Hugh Dickins <hughd@google.com>
381 lines
8.7 KiB
C
381 lines
8.7 KiB
C
/* AFS filesystem file handling
|
|
*
|
|
* Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/writeback.h>
|
|
#include <linux/gfp.h>
|
|
#include "internal.h"
|
|
|
|
static int afs_readpage(struct file *file, struct page *page);
|
|
static void afs_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length);
|
|
static int afs_releasepage(struct page *page, gfp_t gfp_flags);
|
|
static int afs_launder_page(struct page *page);
|
|
|
|
static int afs_readpages(struct file *filp, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages);
|
|
|
|
const struct file_operations afs_file_operations = {
|
|
.open = afs_open,
|
|
.release = afs_release,
|
|
.llseek = generic_file_llseek,
|
|
.read = do_sync_read,
|
|
.write = do_sync_write,
|
|
.aio_read = generic_file_aio_read,
|
|
.aio_write = afs_file_write,
|
|
.mmap = generic_file_readonly_mmap,
|
|
.splice_read = generic_file_splice_read,
|
|
.fsync = afs_fsync,
|
|
.lock = afs_lock,
|
|
.flock = afs_flock,
|
|
};
|
|
|
|
const struct inode_operations afs_file_inode_operations = {
|
|
.getattr = afs_getattr,
|
|
.setattr = afs_setattr,
|
|
.permission = afs_permission,
|
|
};
|
|
|
|
const struct address_space_operations afs_fs_aops = {
|
|
.readpage = afs_readpage,
|
|
.readpages = afs_readpages,
|
|
.set_page_dirty = afs_set_page_dirty,
|
|
.launder_page = afs_launder_page,
|
|
.releasepage = afs_releasepage,
|
|
.invalidatepage = afs_invalidatepage,
|
|
.write_begin = afs_write_begin,
|
|
.write_end = afs_write_end,
|
|
.writepage = afs_writepage,
|
|
.writepages = afs_writepages,
|
|
};
|
|
|
|
/*
|
|
* open an AFS file or directory and attach a key to it
|
|
*/
|
|
int afs_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
struct key *key;
|
|
int ret;
|
|
|
|
_enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);
|
|
|
|
key = afs_request_key(vnode->volume->cell);
|
|
if (IS_ERR(key)) {
|
|
_leave(" = %ld [key]", PTR_ERR(key));
|
|
return PTR_ERR(key);
|
|
}
|
|
|
|
ret = afs_validate(vnode, key);
|
|
if (ret < 0) {
|
|
_leave(" = %d [val]", ret);
|
|
return ret;
|
|
}
|
|
|
|
file->private_data = key;
|
|
_leave(" = 0");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* release an AFS file or directory and discard its key
|
|
*/
|
|
int afs_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
|
|
_enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);
|
|
|
|
key_put(file->private_data);
|
|
_leave(" = 0");
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
/*
|
|
* deal with notification that a page was read from the cache
|
|
*/
|
|
static void afs_file_readpage_read_complete(struct page *page,
|
|
void *data,
|
|
int error)
|
|
{
|
|
_enter("%p,%p,%d", page, data, 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);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* read page from file, directory or symlink, given a key to use
|
|
*/
|
|
int afs_page_filler(void *data, struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct afs_vnode *vnode = AFS_FS_I(inode);
|
|
struct key *key = data;
|
|
size_t len;
|
|
off_t offset;
|
|
int ret;
|
|
|
|
_enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index);
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
ret = -ESTALE;
|
|
if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
|
|
goto error;
|
|
|
|
/* is it cached? */
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
ret = fscache_read_or_alloc_page(vnode->cache,
|
|
page,
|
|
afs_file_readpage_read_complete,
|
|
NULL,
|
|
GFP_KERNEL);
|
|
#else
|
|
ret = -ENOBUFS;
|
|
#endif
|
|
switch (ret) {
|
|
/* read BIO submitted (page in cache) */
|
|
case 0:
|
|
break;
|
|
|
|
/* page not yet cached */
|
|
case -ENODATA:
|
|
_debug("cache said ENODATA");
|
|
goto go_on;
|
|
|
|
/* page will not be cached */
|
|
case -ENOBUFS:
|
|
_debug("cache said ENOBUFS");
|
|
default:
|
|
go_on:
|
|
offset = page->index << PAGE_CACHE_SHIFT;
|
|
len = min_t(size_t, i_size_read(inode) - offset, PAGE_SIZE);
|
|
|
|
/* read the contents of the file from the server into the
|
|
* page */
|
|
ret = afs_vnode_fetch_data(vnode, key, offset, len, page);
|
|
if (ret < 0) {
|
|
if (ret == -ENOENT) {
|
|
_debug("got NOENT from server"
|
|
" - marking file deleted and stale");
|
|
set_bit(AFS_VNODE_DELETED, &vnode->flags);
|
|
ret = -ESTALE;
|
|
}
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
fscache_uncache_page(vnode->cache, page);
|
|
#endif
|
|
BUG_ON(PageFsCache(page));
|
|
goto error;
|
|
}
|
|
|
|
SetPageUptodate(page);
|
|
|
|
/* send the page to the cache */
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
if (PageFsCache(page) &&
|
|
fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) {
|
|
fscache_uncache_page(vnode->cache, page);
|
|
BUG_ON(PageFsCache(page));
|
|
}
|
|
#endif
|
|
unlock_page(page);
|
|
}
|
|
|
|
_leave(" = 0");
|
|
return 0;
|
|
|
|
error:
|
|
SetPageError(page);
|
|
unlock_page(page);
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* read page from file, directory or symlink, given a file to nominate the key
|
|
* to be used
|
|
*/
|
|
static int afs_readpage(struct file *file, struct page *page)
|
|
{
|
|
struct key *key;
|
|
int ret;
|
|
|
|
if (file) {
|
|
key = file->private_data;
|
|
ASSERT(key != NULL);
|
|
ret = afs_page_filler(key, page);
|
|
} else {
|
|
struct inode *inode = page->mapping->host;
|
|
key = afs_request_key(AFS_FS_S(inode->i_sb)->volume->cell);
|
|
if (IS_ERR(key)) {
|
|
ret = PTR_ERR(key);
|
|
} else {
|
|
ret = afs_page_filler(key, page);
|
|
key_put(key);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* read a set of pages
|
|
*/
|
|
static int afs_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages)
|
|
{
|
|
struct key *key = file->private_data;
|
|
struct afs_vnode *vnode;
|
|
int ret = 0;
|
|
|
|
_enter("{%d},{%lu},,%d",
|
|
key_serial(key), mapping->host->i_ino, nr_pages);
|
|
|
|
ASSERT(key != NULL);
|
|
|
|
vnode = AFS_FS_I(mapping->host);
|
|
if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
|
|
_leave(" = -ESTALE");
|
|
return -ESTALE;
|
|
}
|
|
|
|
/* attempt to read as many of the pages as possible */
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
ret = fscache_read_or_alloc_pages(vnode->cache,
|
|
mapping,
|
|
pages,
|
|
&nr_pages,
|
|
afs_file_readpage_read_complete,
|
|
NULL,
|
|
mapping_gfp_mask(mapping));
|
|
#else
|
|
ret = -ENOBUFS;
|
|
#endif
|
|
|
|
switch (ret) {
|
|
/* all pages are being read from the cache */
|
|
case 0:
|
|
BUG_ON(!list_empty(pages));
|
|
BUG_ON(nr_pages != 0);
|
|
_leave(" = 0 [reading all]");
|
|
return 0;
|
|
|
|
/* there were pages that couldn't be read from the cache */
|
|
case -ENODATA:
|
|
case -ENOBUFS:
|
|
break;
|
|
|
|
/* other error */
|
|
default:
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
|
|
/* load the missing pages from the network */
|
|
ret = read_cache_pages(mapping, pages, afs_page_filler, key);
|
|
|
|
_leave(" = %d [netting]", ret);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* write back a dirty page
|
|
*/
|
|
static int afs_launder_page(struct page *page)
|
|
{
|
|
_enter("{%lu}", page->index);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* invalidate part or all of a page
|
|
* - release a page and clean up its private data if offset is 0 (indicating
|
|
* the entire page)
|
|
*/
|
|
static void afs_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
struct afs_writeback *wb = (struct afs_writeback *) page_private(page);
|
|
|
|
_enter("{%lu},%u,%u", page->index, offset, length);
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
/* we clean up only if the entire page is being invalidated */
|
|
if (offset == 0 && length == PAGE_CACHE_SIZE) {
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
if (PageFsCache(page)) {
|
|
struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
|
|
fscache_wait_on_page_write(vnode->cache, page);
|
|
fscache_uncache_page(vnode->cache, page);
|
|
}
|
|
#endif
|
|
|
|
if (PagePrivate(page)) {
|
|
if (wb && !PageWriteback(page)) {
|
|
set_page_private(page, 0);
|
|
afs_put_writeback(wb);
|
|
}
|
|
|
|
if (!page_private(page))
|
|
ClearPagePrivate(page);
|
|
}
|
|
}
|
|
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* release a page and clean up its private state if it's not busy
|
|
* - return true if the page can now be released, false if not
|
|
*/
|
|
static int afs_releasepage(struct page *page, gfp_t gfp_flags)
|
|
{
|
|
struct afs_writeback *wb = (struct afs_writeback *) page_private(page);
|
|
struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
|
|
|
|
_enter("{{%x:%u}[%lu],%lx},%x",
|
|
vnode->fid.vid, vnode->fid.vnode, page->index, page->flags,
|
|
gfp_flags);
|
|
|
|
/* deny if page is being written to the cache and the caller hasn't
|
|
* elected to wait */
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
if (!fscache_maybe_release_page(vnode->cache, page, gfp_flags)) {
|
|
_leave(" = F [cache busy]");
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
if (PagePrivate(page)) {
|
|
if (wb) {
|
|
set_page_private(page, 0);
|
|
afs_put_writeback(wb);
|
|
}
|
|
ClearPagePrivate(page);
|
|
}
|
|
|
|
/* indicate that the page can be released */
|
|
_leave(" = T");
|
|
return 1;
|
|
}
|