diff options
Diffstat (limited to 'fs/logfs/file.c')
-rw-r--r-- | fs/logfs/file.c | 285 |
1 files changed, 0 insertions, 285 deletions
diff --git a/fs/logfs/file.c b/fs/logfs/file.c deleted file mode 100644 index 1db04930ad57..000000000000 --- a/fs/logfs/file.c +++ /dev/null @@ -1,285 +0,0 @@ -/* - * fs/logfs/file.c - prepare_write, commit_write and friends - * - * As should be obvious for Linux kernel code, license is GPLv2 - * - * Copyright (c) 2005-2008 Joern Engel <joern@logfs.org> - */ -#include "logfs.h" -#include <linux/sched.h> -#include <linux/writeback.h> - -static int logfs_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned flags, - struct page **pagep, void **fsdata) -{ - struct inode *inode = mapping->host; - struct page *page; - pgoff_t index = pos >> PAGE_SHIFT; - - page = grab_cache_page_write_begin(mapping, index, flags); - if (!page) - return -ENOMEM; - *pagep = page; - - if ((len == PAGE_SIZE) || PageUptodate(page)) - return 0; - if ((pos & PAGE_MASK) >= i_size_read(inode)) { - unsigned start = pos & (PAGE_SIZE - 1); - unsigned end = start + len; - - /* Reading beyond i_size is simple: memset to zero */ - zero_user_segments(page, 0, start, end, PAGE_SIZE); - return 0; - } - return logfs_readpage_nolock(page); -} - -static int logfs_write_end(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, struct page *page, - void *fsdata) -{ - struct inode *inode = mapping->host; - pgoff_t index = page->index; - unsigned start = pos & (PAGE_SIZE - 1); - unsigned end = start + copied; - int ret = 0; - - BUG_ON(PAGE_SIZE != inode->i_sb->s_blocksize); - BUG_ON(page->index > I3_BLOCKS); - - if (copied < len) { - /* - * Short write of a non-initialized paged. Just tell userspace - * to retry the entire page. - */ - if (!PageUptodate(page)) { - copied = 0; - goto out; - } - } - if (copied == 0) - goto out; /* FIXME: do we need to update inode? */ - - if (i_size_read(inode) < (index << PAGE_SHIFT) + end) { - i_size_write(inode, (index << PAGE_SHIFT) + end); - mark_inode_dirty_sync(inode); - } - - SetPageUptodate(page); - if (!PageDirty(page)) { - if (!get_page_reserve(inode, page)) - __set_page_dirty_nobuffers(page); - else - ret = logfs_write_buf(inode, page, WF_LOCK); - } -out: - unlock_page(page); - put_page(page); - return ret ? ret : copied; -} - -int logfs_readpage(struct file *file, struct page *page) -{ - int ret; - - ret = logfs_readpage_nolock(page); - unlock_page(page); - return ret; -} - -/* Clear the page's dirty flag in the radix tree. */ -/* TODO: mucking with PageWriteback is silly. Add a generic function to clear - * the dirty bit from the radix tree for filesystems that don't have to wait - * for page writeback to finish (i.e. any compressing filesystem). - */ -static void clear_radix_tree_dirty(struct page *page) -{ - BUG_ON(PagePrivate(page) || page->private); - set_page_writeback(page); - end_page_writeback(page); -} - -static int __logfs_writepage(struct page *page) -{ - struct inode *inode = page->mapping->host; - int err; - - err = logfs_write_buf(inode, page, WF_LOCK); - if (err) - set_page_dirty(page); - else - clear_radix_tree_dirty(page); - unlock_page(page); - return err; -} - -static int logfs_writepage(struct page *page, struct writeback_control *wbc) -{ - struct inode *inode = page->mapping->host; - loff_t i_size = i_size_read(inode); - pgoff_t end_index = i_size >> PAGE_SHIFT; - unsigned offset; - u64 bix; - level_t level; - - log_file("logfs_writepage(%lx, %lx, %p)\n", inode->i_ino, page->index, - page); - - logfs_unpack_index(page->index, &bix, &level); - - /* Indirect blocks are never truncated */ - if (level != 0) - return __logfs_writepage(page); - - /* - * TODO: everything below is a near-verbatim copy of nobh_writepage(). - * The relevant bits should be factored out after logfs is merged. - */ - - /* Is the page fully inside i_size? */ - if (bix < end_index) - return __logfs_writepage(page); - - /* Is the page fully outside i_size? (truncate in progress) */ - offset = i_size & (PAGE_SIZE-1); - if (bix > end_index || offset == 0) { - unlock_page(page); - return 0; /* don't care */ - } - - /* - * The page straddles i_size. It must be zeroed out on each and every - * writepage invokation because it may be mmapped. "A file is mapped - * in multiples of the page size. For a file that is not a multiple of - * the page size, the remaining memory is zeroed when mapped, and - * writes to that region are not written out to the file." - */ - zero_user_segment(page, offset, PAGE_SIZE); - return __logfs_writepage(page); -} - -static void logfs_invalidatepage(struct page *page, unsigned int offset, - unsigned int length) -{ - struct logfs_block *block = logfs_block(page); - - if (block->reserved_bytes) { - struct super_block *sb = page->mapping->host->i_sb; - struct logfs_super *super = logfs_super(sb); - - super->s_dirty_pages -= block->reserved_bytes; - block->ops->free_block(sb, block); - BUG_ON(bitmap_weight(block->alias_map, LOGFS_BLOCK_FACTOR)); - } else - move_page_to_btree(page); - BUG_ON(PagePrivate(page) || page->private); -} - -static int logfs_releasepage(struct page *page, gfp_t only_xfs_uses_this) -{ - return 0; /* None of these are easy to release */ -} - - -long logfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) -{ - struct inode *inode = file_inode(file); - struct logfs_inode *li = logfs_inode(inode); - unsigned int oldflags, flags; - int err; - - switch (cmd) { - case FS_IOC_GETFLAGS: - flags = li->li_flags & LOGFS_FL_USER_VISIBLE; - return put_user(flags, (int __user *)arg); - case FS_IOC_SETFLAGS: - if (IS_RDONLY(inode)) - return -EROFS; - - if (!inode_owner_or_capable(inode)) - return -EACCES; - - err = get_user(flags, (int __user *)arg); - if (err) - return err; - - inode_lock(inode); - oldflags = li->li_flags; - flags &= LOGFS_FL_USER_MODIFIABLE; - flags |= oldflags & ~LOGFS_FL_USER_MODIFIABLE; - li->li_flags = flags; - inode_unlock(inode); - - inode->i_ctime = current_time(inode); - mark_inode_dirty_sync(inode); - return 0; - - default: - return -ENOTTY; - } -} - -int logfs_fsync(struct file *file, loff_t start, loff_t end, int datasync) -{ - struct super_block *sb = file->f_mapping->host->i_sb; - struct inode *inode = file->f_mapping->host; - int ret; - - ret = filemap_write_and_wait_range(inode->i_mapping, start, end); - if (ret) - return ret; - - inode_lock(inode); - logfs_get_wblocks(sb, NULL, WF_LOCK); - logfs_write_anchor(sb); - logfs_put_wblocks(sb, NULL, WF_LOCK); - inode_unlock(inode); - - return 0; -} - -static int logfs_setattr(struct dentry *dentry, struct iattr *attr) -{ - struct inode *inode = d_inode(dentry); - int err = 0; - - err = setattr_prepare(dentry, attr); - if (err) - return err; - - if (attr->ia_valid & ATTR_SIZE) { - err = logfs_truncate(inode, attr->ia_size); - if (err) - return err; - } - - setattr_copy(inode, attr); - mark_inode_dirty(inode); - return 0; -} - -const struct inode_operations logfs_reg_iops = { - .setattr = logfs_setattr, -}; - -const struct file_operations logfs_reg_fops = { - .read_iter = generic_file_read_iter, - .write_iter = generic_file_write_iter, - .fsync = logfs_fsync, - .unlocked_ioctl = logfs_ioctl, - .llseek = generic_file_llseek, - .mmap = generic_file_readonly_mmap, - .open = generic_file_open, -}; - -const struct address_space_operations logfs_reg_aops = { - .invalidatepage = logfs_invalidatepage, - .readpage = logfs_readpage, - .releasepage = logfs_releasepage, - .set_page_dirty = __set_page_dirty_nobuffers, - .writepage = logfs_writepage, - .writepages = generic_writepages, - .write_begin = logfs_write_begin, - .write_end = logfs_write_end, -}; |