--- /dev/null
+/*
+ * 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_add_unless(&REISERFS_I(inode)->openers, -1, 1))
+ return 0;
+
+ mutex_lock(&REISERFS_I(inode)->tailpack);
+
+ if (!atomic_dec_and_test(&REISERFS_I(inode)->openers)) {
+ mutex_unlock(&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 = filemap_write_and_wait_range(inode->i_mapping, start, end);
+ if (err)
+ return err;
+
+ mutex_lock(&inode->i_mutex);
+ 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, NULL);
+ mutex_unlock(&inode->i_mutex);
+ 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_CACHE_SHIFT;
+ int new;
+ int logit = reiserfs_file_data_log(inode);
+ struct super_block *s = inode->i_sb;
+ int bh_per_page = PAGE_CACHE_SIZE / s->s_blocksize;
+ struct reiserfs_transaction_handle th;
+ int ret = 0;
+
+ th.t_trans_id = 0;
+ blocksize = 1 << inode->i_blkbits;
+
+ 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,
+ .setxattr = reiserfs_setxattr,
+ .getxattr = reiserfs_getxattr,
+ .listxattr = reiserfs_listxattr,
+ .removexattr = reiserfs_removexattr,
+ .permission = reiserfs_permission,
+ .get_acl = reiserfs_get_acl,
+ .set_acl = reiserfs_set_acl,
+};
Code Review / kvmfornfv.git / blobdiff