-/* file.c: AFS filesystem file handling
+/* AFS filesystem file handling
*
- * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * 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
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
-#include "volume.h"
-#include "vnode.h"
-#include <rxrpc/call.h>
+#include <linux/writeback.h>
#include "internal.h"
-#if 0
-static int afs_file_open(struct inode *inode, struct file *file);
-static int afs_file_release(struct inode *inode, struct file *file);
-#endif
-
-static int afs_file_readpage(struct file *file, struct page *page);
-static void afs_file_invalidatepage(struct page *page, unsigned long offset);
-static int afs_file_releasepage(struct page *page, gfp_t gfp_flags);
+static int afs_readpage(struct file *file, struct page *page);
+static void afs_invalidatepage(struct page *page, unsigned long offset);
+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_inode_getattr,
+ .getattr = afs_getattr,
+ .setattr = afs_setattr,
+ .permission = afs_permission,
};
const struct address_space_operations afs_fs_aops = {
- .readpage = afs_file_readpage,
- .set_page_dirty = __set_page_dirty_nobuffers,
- .releasepage = afs_file_releasepage,
- .invalidatepage = afs_file_invalidatepage,
+ .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,
};
-/*****************************************************************************/
/*
- * deal with notification that a page was read from the cache
+ * open an AFS file or directory and attach a key to it
*/
-#ifdef AFS_CACHING_SUPPORT
-static void afs_file_readpage_read_complete(void *cookie_data,
- struct page *page,
- void *data,
- int error)
+int afs_open(struct inode *inode, struct file *file)
{
- _enter("%p,%p,%p,%d", cookie_data, page, data, error);
+ struct afs_vnode *vnode = AFS_FS_I(inode);
+ struct key *key;
+ int ret;
- if (error)
- SetPageError(page);
- else
- SetPageUptodate(page);
- unlock_page(page);
+ _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);
-} /* end afs_file_readpage_read_complete() */
-#endif
+ 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;
+}
-/*****************************************************************************/
/*
- * deal with notification that a page was written to the cache
+ * release an AFS file or directory and discard its key
*/
-#ifdef AFS_CACHING_SUPPORT
-static void afs_file_readpage_write_complete(void *cookie_data,
- struct page *page,
- void *data,
- int error)
+int afs_release(struct inode *inode, struct file *file)
{
- _enter("%p,%p,%p,%d", cookie_data, page, data, error);
+ struct afs_vnode *vnode = AFS_FS_I(inode);
- unlock_page(page);
+ _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode);
-} /* end afs_file_readpage_write_complete() */
-#endif
+ key_put(file->private_data);
+ _leave(" = 0");
+ return 0;
+}
-/*****************************************************************************/
+#ifdef CONFIG_AFS_FSCACHE
/*
- * AFS read page from file (or symlink)
+ * deal with notification that a page was read from the cache
*/
-static int afs_file_readpage(struct file *file, struct page *page)
+static void afs_file_readpage_read_complete(struct page *page,
+ void *data,
+ int error)
{
- struct afs_rxfs_fetch_descriptor desc;
-#ifdef AFS_CACHING_SUPPORT
- struct cachefs_page *pageio;
+ _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
+
+/*
+ * AFS read page from file, directory or symlink
+ */
+static int afs_readpage(struct file *file, struct page *page)
+{
struct afs_vnode *vnode;
struct inode *inode;
+ struct key *key;
+ size_t len;
+ off_t offset;
int ret;
inode = page->mapping->host;
- _enter("{%lu},{%lu}", inode->i_ino, page->index);
+ if (file) {
+ key = file->private_data;
+ ASSERT(key != NULL);
+ } else {
+ key = afs_request_key(AFS_FS_S(inode->i_sb)->volume->cell);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error_nokey;
+ }
+ }
+
+ _enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index);
vnode = AFS_FS_I(inode);
BUG_ON(!PageLocked(page));
ret = -ESTALE;
- if (vnode->flags & AFS_VNODE_DELETED)
- goto error;
-
-#ifdef AFS_CACHING_SUPPORT
- ret = cachefs_page_get_private(page, &pageio, GFP_NOIO);
- if (ret < 0)
+ if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
goto error;
/* is it cached? */
- ret = cachefs_read_or_alloc_page(vnode->cache,
+#ifdef CONFIG_AFS_FSCACHE
+ ret = fscache_read_or_alloc_page(vnode->cache,
page,
afs_file_readpage_read_complete,
NULL,
#else
ret = -ENOBUFS;
#endif
-
switch (ret) {
- /* read BIO submitted and wb-journal entry found */
- case 1:
- BUG(); // TODO - handle wb-journal match
-
/* read BIO submitted (page in cache) */
case 0:
break;
- /* no page available in cache */
- case -ENOBUFS:
+ /* page not yet cached */
case -ENODATA:
- default:
- desc.fid = vnode->fid;
- desc.offset = page->index << PAGE_CACHE_SHIFT;
- desc.size = min((size_t) (inode->i_size - desc.offset),
- (size_t) PAGE_SIZE);
- desc.buffer = kmap(page);
+ _debug("cache said ENODATA");
+ goto go_on;
- clear_page(desc.buffer);
+ /* 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, &desc);
- kunmap(page);
+ ret = afs_vnode_fetch_data(vnode, key, offset, len, page);
if (ret < 0) {
- if (ret==-ENOENT) {
+ if (ret == -ENOENT) {
_debug("got NOENT from server"
" - marking file deleted and stale");
- vnode->flags |= AFS_VNODE_DELETED;
+ set_bit(AFS_VNODE_DELETED, &vnode->flags);
ret = -ESTALE;
}
-#ifdef AFS_CACHING_SUPPORT
- cachefs_uncache_page(vnode->cache, page);
+#ifdef CONFIG_AFS_FSCACHE
+ fscache_uncache_page(vnode->cache, page);
#endif
+ BUG_ON(PageFsCache(page));
goto error;
}
SetPageUptodate(page);
-#ifdef AFS_CACHING_SUPPORT
- if (cachefs_write_page(vnode->cache,
- page,
- afs_file_readpage_write_complete,
- NULL,
- GFP_KERNEL) != 0
- ) {
- cachefs_uncache_page(vnode->cache, page);
- unlock_page(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));
}
-#else
- unlock_page(page);
#endif
+ unlock_page(page);
}
+ if (!file)
+ key_put(key);
_leave(" = 0");
return 0;
- error:
+error:
SetPageError(page);
unlock_page(page);
-
+ if (!file)
+ key_put(key);
+error_nokey:
_leave(" = %d", ret);
return ret;
+}
-} /* end afs_file_readpage() */
-
-/*****************************************************************************/
/*
- * get a page cookie for the specified page
+ * read a set of pages
*/
-#ifdef AFS_CACHING_SUPPORT
-int afs_cache_get_page_cookie(struct page *page,
- struct cachefs_page **_page_cookie)
+static int afs_readpages(struct file *file, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
{
- int ret;
+ struct afs_vnode *vnode;
+ int ret = 0;
- _enter("");
- ret = cachefs_page_get_private(page,_page_cookie, GFP_NOIO);
+ _enter(",{%lu},,%d", mapping->host->i_ino, nr_pages);
- _leave(" = %d", ret);
- return ret;
-} /* end afs_cache_get_page_cookie() */
+ vnode = AFS_FS_I(mapping->host);
+ if (vnode->flags & AFS_VNODE_DELETED) {
+ _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, (void *) afs_readpage, file);
+
+ _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_file_invalidatepage(struct page *page, unsigned long offset)
+static void afs_invalidatepage(struct page *page, unsigned long offset)
{
- int ret = 1;
+ struct afs_writeback *wb = (struct afs_writeback *) page_private(page);
_enter("{%lu},%lu", page->index, offset);
BUG_ON(!PageLocked(page));
- if (PagePrivate(page)) {
-#ifdef AFS_CACHING_SUPPORT
- struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
- cachefs_uncache_page(vnode->cache,page);
+ /* we clean up only if the entire page is being invalidated */
+ if (offset == 0) {
+#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
- /* We release buffers only if the entire page is being
- * invalidated.
- * The get_block cached value has been unconditionally
- * invalidated, so real IO is not possible anymore.
- */
- if (offset == 0) {
- BUG_ON(!PageLocked(page));
-
- ret = 0;
- if (!PageWriteback(page))
- ret = page->mapping->a_ops->releasepage(page,
- 0);
- /* possibly should BUG_ON(!ret); - neilb */
+ if (PagePrivate(page)) {
+ if (wb && !PageWriteback(page)) {
+ set_page_private(page, 0);
+ afs_put_writeback(wb);
+ }
+
+ if (!page_private(page))
+ ClearPagePrivate(page);
}
}
- _leave(" = %d", ret);
-} /* end afs_file_invalidatepage() */
+ _leave("");
+}
-/*****************************************************************************/
/*
- * release a page and cleanup its private data
+ * 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_file_releasepage(struct page *page, gfp_t gfp_flags)
+static int afs_releasepage(struct page *page, gfp_t gfp_flags)
{
- struct cachefs_page *pageio;
-
- _enter("{%lu},%x", page->index, gfp_flags);
-
- if (PagePrivate(page)) {
-#ifdef AFS_CACHING_SUPPORT
- struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
- cachefs_uncache_page(vnode->cache, page);
+ 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
- pageio = (struct cachefs_page *) page_private(page);
- set_page_private(page, 0);
+ if (PagePrivate(page)) {
+ if (wb) {
+ set_page_private(page, 0);
+ afs_put_writeback(wb);
+ }
ClearPagePrivate(page);
-
- kfree(pageio);
}
- _leave(" = 0");
- return 0;
-} /* end afs_file_releasepage() */
+ /* indicate that the page can be released */
+ _leave(" = T");
+ return 1;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff