diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/afs/file.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/afs/file.c')
-rw-r--r-- | fs/afs/file.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/fs/afs/file.c b/fs/afs/file.c new file mode 100644 index 000000000000..6b6bb7c8abf6 --- /dev/null +++ b/fs/afs/file.c @@ -0,0 +1,305 @@ +/* file.c: AFS filesystem file handling + * + * Copyright (C) 2002 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/sched.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/pagemap.h> +#include <linux/buffer_head.h> +#include "volume.h" +#include "vnode.h" +#include <rxrpc/call.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 int afs_file_invalidatepage(struct page *page, unsigned long offset); +static int afs_file_releasepage(struct page *page, int gfp_flags); + +static ssize_t afs_file_write(struct file *file, const char __user *buf, + size_t size, loff_t *off); + +struct inode_operations afs_file_inode_operations = { + .getattr = afs_inode_getattr, +}; + +struct file_operations afs_file_file_operations = { + .read = generic_file_read, + .write = afs_file_write, + .mmap = generic_file_mmap, +#if 0 + .open = afs_file_open, + .release = afs_file_release, + .fsync = afs_file_fsync, +#endif +}; + +struct address_space_operations afs_fs_aops = { + .readpage = afs_file_readpage, + .sync_page = block_sync_page, + .set_page_dirty = __set_page_dirty_nobuffers, + .releasepage = afs_file_releasepage, + .invalidatepage = afs_file_invalidatepage, +}; + +/*****************************************************************************/ +/* + * AFS file write + */ +static ssize_t afs_file_write(struct file *file, const char __user *buf, + size_t size, loff_t *off) +{ + struct afs_vnode *vnode; + + vnode = AFS_FS_I(file->f_dentry->d_inode); + if (vnode->flags & AFS_VNODE_DELETED) + return -ESTALE; + + return -EIO; +} /* end afs_file_write() */ + +/*****************************************************************************/ +/* + * deal with notification that a page was read from the cache + */ +#ifdef AFS_CACHING_SUPPORT +static void afs_file_readpage_read_complete(void *cookie_data, + struct page *page, + void *data, + int error) +{ + _enter("%p,%p,%p,%d", cookie_data, page, data, error); + + if (error) + SetPageError(page); + else + SetPageUptodate(page); + unlock_page(page); + +} /* end afs_file_readpage_read_complete() */ +#endif + +/*****************************************************************************/ +/* + * deal with notification that a page was written to the cache + */ +#ifdef AFS_CACHING_SUPPORT +static void afs_file_readpage_write_complete(void *cookie_data, + struct page *page, + void *data, + int error) +{ + _enter("%p,%p,%p,%d", cookie_data, page, data, error); + + unlock_page(page); + +} /* end afs_file_readpage_write_complete() */ +#endif + +/*****************************************************************************/ +/* + * AFS read page from file (or symlink) + */ +static int afs_file_readpage(struct file *file, struct page *page) +{ + struct afs_rxfs_fetch_descriptor desc; +#ifdef AFS_CACHING_SUPPORT + struct cachefs_page *pageio; +#endif + struct afs_vnode *vnode; + struct inode *inode; + int ret; + + inode = page->mapping->host; + + _enter("{%lu},{%lu}", inode->i_ino, page->index); + + vnode = AFS_FS_I(inode); + + if (!PageLocked(page)) + PAGE_BUG(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) + goto error; + + /* is it cached? */ + ret = cachefs_read_or_alloc_page(vnode->cache, + page, + afs_file_readpage_read_complete, + NULL, + GFP_KERNEL); +#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: + 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); + + clear_page(desc.buffer); + + /* read the contents of the file from the server into the + * page */ + ret = afs_vnode_fetch_data(vnode, &desc); + kunmap(page); + if (ret < 0) { + if (ret==-ENOENT) { + _debug("got NOENT from server" + " - marking file deleted and stale"); + vnode->flags |= AFS_VNODE_DELETED; + ret = -ESTALE; + } + +#ifdef AFS_CACHING_SUPPORT + cachefs_uncache_page(vnode->cache, page); +#endif + 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); + } +#else + unlock_page(page); +#endif + } + + _leave(" = 0"); + return 0; + + error: + SetPageError(page); + unlock_page(page); + + _leave(" = %d", ret); + return ret; + +} /* end afs_file_readpage() */ + +/*****************************************************************************/ +/* + * get a page cookie for the specified page + */ +#ifdef AFS_CACHING_SUPPORT +int afs_cache_get_page_cookie(struct page *page, + struct cachefs_page **_page_cookie) +{ + int ret; + + _enter(""); + ret = cachefs_page_get_private(page,_page_cookie, GFP_NOIO); + + _leave(" = %d", ret); + return ret; +} /* end afs_cache_get_page_cookie() */ +#endif + +/*****************************************************************************/ +/* + * invalidate part or all of a page + */ +static int afs_file_invalidatepage(struct page *page, unsigned long offset) +{ + int ret = 1; + + _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); +#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); + } + } + + _leave(" = %d", ret); + return ret; +} /* end afs_file_invalidatepage() */ + +/*****************************************************************************/ +/* + * release a page and cleanup its private data + */ +static int afs_file_releasepage(struct page *page, int 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); +#endif + + pageio = (struct cachefs_page *) page->private; + page->private = 0; + ClearPagePrivate(page); + + if (pageio) + kfree(pageio); + } + + _leave(" = 0"); + return 0; +} /* end afs_file_releasepage() */ |