/* * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README */ #include <linux/time.h> #include "reiserfs.h" #include "acl.h" #include "xattr.h" #include <linux/uaccess.h> #include <linux/pagemap.h> #include <linux/swap.h> #include <linux/writeback.h> #include <linux/blkdev.h> #include <linux/buffer_head.h> #include <linux/quotaops.h> /* * We pack the tails of files on file close, not at the time they are written. * This implies an unnecessary copy of the tail and an unnecessary indirect item * insertion/balancing, for files that are written in one write. * It avoids unnecessary tail packings (balances) for files that are written in * multiple writes and are small enough to have tails. * * file_release is called by the VFS layer when the file is closed. If * this is the last open file descriptor, and the file * small enough to have a tail, and the tail is currently in an * unformatted node, the tail is converted back into a direct item. * * We use reiserfs_truncate_file to pack the tail, since it already has * all the conditions coded. */ static int reiserfs_file_release(struct inode *inode, struct file *filp) { struct reiserfs_transaction_handle th; int err; int jbegin_failure = 0; BUG_ON(!S_ISREG(inode->i_mode)); if (!atomic_dec_and_mutex_lock(&REISERFS_I(inode)->openers, &REISERFS_I(inode)->tailpack)) return 0; /* fast out for when nothing needs to be done */ if ((!(REISERFS_I(inode)->i_flags & i_pack_on_close_mask) || !tail_has_to_be_packed(inode)) && REISERFS_I(inode)->i_prealloc_count <= 0) { mutex_unlock(&REISERFS_I(inode)->tailpack); return 0; } reiserfs_write_lock(inode->i_sb); /* * freeing preallocation only involves relogging blocks that * are already in the current transaction. preallocation gets * freed at the end of each transaction, so it is impossible for * us to log any additional blocks (including quota blocks) */ err = journal_begin(&th, inode->i_sb, 1); if (err) { /* * uh oh, we can't allow the inode to go away while there * is still preallocation blocks pending. Try to join the * aborted transaction */ jbegin_failure = err; err = journal_join_abort(&th, inode->i_sb); if (err) { /* * hmpf, our choices here aren't good. We can pin * the inode which will disallow unmount from ever * happening, we can do nothing, which will corrupt * random memory on unmount, or we can forcibly * remove the file from the preallocation list, which * will leak blocks on disk. Lets pin the inode * and let the admin know what is going on. */ igrab(inode); reiserfs_warning(inode->i_sb, "clm-9001", "pinning inode %lu because the " "preallocation can't be freed", inode->i_ino); goto out; } } reiserfs_update_inode_transaction(inode); #ifdef REISERFS_PREALLOCATE reiserfs_discard_prealloc(&th, inode); #endif err = journal_end(&th); /* copy back the error code from journal_begin */ if (!err) err = jbegin_failure; if (!err && (REISERFS_I(inode)->i_flags & i_pack_on_close_mask) && tail_has_to_be_packed(inode)) { /* * if regular file is released by last holder and it has been * appended (we append by unformatted node only) or its direct * item(s) had to be converted, then it may have to be * indirect2direct converted */ err = reiserfs_truncate_file(inode, 0); } out: reiserfs_write_unlock(inode->i_sb); mutex_unlock(&REISERFS_I(inode)->tailpack); return err; } static int reiserfs_file_open(struct inode *inode, struct file *file) { int err = dquot_file_open(inode, file); /* somebody might be tailpacking on final close; wait for it */ if (!atomic_inc_not_zero(&REISERFS_I(inode)->openers)) { mutex_lock(&REISERFS_I(inode)->tailpack); atomic_inc(&REISERFS_I(inode)->openers); mutex_unlock(&REISERFS_I(inode)->tailpack); } return err; } void reiserfs_vfs_truncate_file(struct inode *inode) { mutex_lock(&REISERFS_I(inode)->tailpack); reiserfs_truncate_file(inode, 1); mutex_unlock(&REISERFS_I(inode)->tailpack); } /* Sync a reiserfs file. */ /* * FIXME: sync_mapping_buffers() never has anything to sync. Can * be removed... */ static int reiserfs_sync_file(struct file *filp, loff_t start, loff_t end, int datasync) { struct inode *inode = filp->f_mapping->host; int err; int barrier_done; err = file_write_and_wait_range(filp, start, end); if (err) return err; inode_lock(inode); BUG_ON(!S_ISREG(inode->i_mode)); err = sync_mapping_buffers(inode->i_mapping); reiserfs_write_lock(inode->i_sb); barrier_done = reiserfs_commit_for_inode(inode); reiserfs_write_unlock(inode->i_sb); if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb)) blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); inode_unlock(inode); if (barrier_done < 0) return barrier_done; return (err < 0) ? -EIO : 0; } /* taken fs/buffer.c:__block_commit_write */ int reiserfs_commit_page(struct inode *inode, struct page *page, unsigned from, unsigned to) { unsigned block_start, block_end; int partial = 0; unsigned blocksize; struct buffer_head *bh, *head; unsigned long i_size_index = inode->i_size >> PAGE_SHIFT; int new; int logit = reiserfs_file_data_log(inode); struct super_block *s = inode->i_sb; int bh_per_page = PAGE_SIZE / s->s_blocksize; struct reiserfs_transaction_handle th; int ret = 0; th.t_trans_id = 0; blocksize = i_blocksize(inode); if (logit) { reiserfs_write_lock(s); ret = journal_begin(&th, s, bh_per_page + 1); if (ret) goto drop_write_lock; reiserfs_update_inode_transaction(inode); } for (bh = head = page_buffers(page), block_start = 0; bh != head || !block_start; block_start = block_end, bh = bh->b_this_page) { new = buffer_new(bh); clear_buffer_new(bh); block_end = block_start + blocksize; if (block_end <= from || block_start >= to) { if (!buffer_uptodate(bh)) partial = 1; } else { set_buffer_uptodate(bh); if (logit) { reiserfs_prepare_for_journal(s, bh, 1); journal_mark_dirty(&th, bh); } else if (!buffer_dirty(bh)) { mark_buffer_dirty(bh); /* * do data=ordered on any page past the end * of file and any buffer marked BH_New. */ if (reiserfs_data_ordered(inode->i_sb) && (new || page->index >= i_size_index)) { reiserfs_add_ordered_list(inode, bh); } } } } if (logit) { ret = journal_end(&th); drop_write_lock: reiserfs_write_unlock(s); } /* * If this is a partial write which happened to make all buffers * uptodate then we can optimize away a bogus readpage() for * the next read(). Here we 'discover' whether the page went * uptodate as a result of this (potentially partial) write. */ if (!partial) SetPageUptodate(page); return ret; } const struct file_operations reiserfs_file_operations = { .unlocked_ioctl = reiserfs_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = reiserfs_compat_ioctl, #endif .mmap = generic_file_mmap, .open = reiserfs_file_open, .release = reiserfs_file_release, .fsync = reiserfs_sync_file, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, .llseek = generic_file_llseek, }; const struct inode_operations reiserfs_file_inode_operations = { .setattr = reiserfs_setattr, .listxattr = reiserfs_listxattr, .permission = reiserfs_permission, .get_acl = reiserfs_get_acl, .set_acl = reiserfs_set_acl, };