--- /dev/null
+/*
+ * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include "reiserfs.h"
+#include <linux/stat.h>
+#include <linux/buffer_head.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+extern const struct reiserfs_key MIN_KEY;
+
+static int reiserfs_readdir(struct file *, struct dir_context *);
+static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end,
+ int datasync);
+
+const struct file_operations reiserfs_dir_operations = {
+ .llseek = generic_file_llseek,
+ .read = generic_read_dir,
+ .iterate = reiserfs_readdir,
+ .fsync = reiserfs_dir_fsync,
+ .unlocked_ioctl = reiserfs_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = reiserfs_compat_ioctl,
+#endif
+};
+
+static int reiserfs_dir_fsync(struct file *filp, loff_t start, loff_t end,
+ int datasync)
+{
+ struct inode *inode = filp->f_mapping->host;
+ int err;
+
+ err = filemap_write_and_wait_range(inode->i_mapping, start, end);
+ if (err)
+ return err;
+
+ mutex_lock(&inode->i_mutex);
+ reiserfs_write_lock(inode->i_sb);
+ err = reiserfs_commit_for_inode(inode);
+ reiserfs_write_unlock(inode->i_sb);
+ mutex_unlock(&inode->i_mutex);
+ if (err < 0)
+ return err;
+ return 0;
+}
+
+#define store_ih(where,what) copy_item_head (where, what)
+
+static inline bool is_privroot_deh(struct inode *dir, struct reiserfs_de_head *deh)
+{
+ struct dentry *privroot = REISERFS_SB(dir->i_sb)->priv_root;
+ return (d_really_is_positive(privroot) &&
+ deh->deh_objectid == INODE_PKEY(d_inode(privroot))->k_objectid);
+}
+
+int reiserfs_readdir_inode(struct inode *inode, struct dir_context *ctx)
+{
+
+ /* key of current position in the directory (key of directory entry) */
+ struct cpu_key pos_key;
+
+ INITIALIZE_PATH(path_to_entry);
+ struct buffer_head *bh;
+ int item_num, entry_num;
+ const struct reiserfs_key *rkey;
+ struct item_head *ih, tmp_ih;
+ int search_res;
+ char *local_buf;
+ loff_t next_pos;
+ char small_buf[32]; /* avoid kmalloc if we can */
+ struct reiserfs_dir_entry de;
+ int ret = 0;
+ int depth;
+
+ reiserfs_write_lock(inode->i_sb);
+
+ reiserfs_check_lock_depth(inode->i_sb, "readdir");
+
+ /*
+ * form key for search the next directory entry using
+ * f_pos field of file structure
+ */
+ make_cpu_key(&pos_key, inode, ctx->pos ?: DOT_OFFSET, TYPE_DIRENTRY, 3);
+ next_pos = cpu_key_k_offset(&pos_key);
+
+ path_to_entry.reada = PATH_READA;
+ while (1) {
+research:
+ /*
+ * search the directory item, containing entry with
+ * specified key
+ */
+ search_res =
+ search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
+ &de);
+ if (search_res == IO_ERROR) {
+ /*
+ * FIXME: we could just skip part of directory
+ * which could not be read
+ */
+ ret = -EIO;
+ goto out;
+ }
+ entry_num = de.de_entry_num;
+ bh = de.de_bh;
+ item_num = de.de_item_num;
+ ih = de.de_ih;
+ store_ih(&tmp_ih, ih);
+
+ /* we must have found item, that is item of this directory, */
+ RFALSE(COMP_SHORT_KEYS(&ih->ih_key, &pos_key),
+ "vs-9000: found item %h does not match to dir we readdir %K",
+ ih, &pos_key);
+ RFALSE(item_num > B_NR_ITEMS(bh) - 1,
+ "vs-9005 item_num == %d, item amount == %d",
+ item_num, B_NR_ITEMS(bh));
+
+ /*
+ * and entry must be not more than number of entries
+ * in the item
+ */
+ RFALSE(ih_entry_count(ih) < entry_num,
+ "vs-9010: entry number is too big %d (%d)",
+ entry_num, ih_entry_count(ih));
+
+ /*
+ * go through all entries in the directory item beginning
+ * from the entry, that has been found
+ */
+ if (search_res == POSITION_FOUND
+ || entry_num < ih_entry_count(ih)) {
+ struct reiserfs_de_head *deh =
+ B_I_DEH(bh, ih) + entry_num;
+
+ for (; entry_num < ih_entry_count(ih);
+ entry_num++, deh++) {
+ int d_reclen;
+ char *d_name;
+ ino_t d_ino;
+ loff_t cur_pos = deh_offset(deh);
+
+ /* it is hidden entry */
+ if (!de_visible(deh))
+ continue;
+ d_reclen = entry_length(bh, ih, entry_num);
+ d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
+
+ if (d_reclen <= 0 ||
+ d_name + d_reclen > bh->b_data + bh->b_size) {
+ /*
+ * There is corrupted data in entry,
+ * We'd better stop here
+ */
+ pathrelse(&path_to_entry);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (!d_name[d_reclen - 1])
+ d_reclen = strlen(d_name);
+
+ /* too big to send back to VFS */
+ if (d_reclen >
+ REISERFS_MAX_NAME(inode->i_sb->
+ s_blocksize)) {
+ continue;
+ }
+
+ /* Ignore the .reiserfs_priv entry */
+ if (is_privroot_deh(inode, deh))
+ continue;
+
+ ctx->pos = deh_offset(deh);
+ d_ino = deh_objectid(deh);
+ if (d_reclen <= 32) {
+ local_buf = small_buf;
+ } else {
+ local_buf = kmalloc(d_reclen,
+ GFP_NOFS);
+ if (!local_buf) {
+ pathrelse(&path_to_entry);
+ ret = -ENOMEM;
+ goto out;
+ }
+ if (item_moved(&tmp_ih, &path_to_entry)) {
+ kfree(local_buf);
+ goto research;
+ }
+ }
+
+ /*
+ * Note, that we copy name to user space via
+ * temporary buffer (local_buf) because
+ * filldir will block if user space buffer is
+ * swapped out. At that time entry can move to
+ * somewhere else
+ */
+ memcpy(local_buf, d_name, d_reclen);
+
+ /*
+ * Since filldir might sleep, we can release
+ * the write lock here for other waiters
+ */
+ depth = reiserfs_write_unlock_nested(inode->i_sb);
+ if (!dir_emit
+ (ctx, local_buf, d_reclen, d_ino,
+ DT_UNKNOWN)) {
+ reiserfs_write_lock_nested(inode->i_sb, depth);
+ if (local_buf != small_buf) {
+ kfree(local_buf);
+ }
+ goto end;
+ }
+ reiserfs_write_lock_nested(inode->i_sb, depth);
+ if (local_buf != small_buf) {
+ kfree(local_buf);
+ }
+
+ /* deh_offset(deh) may be invalid now. */
+ next_pos = cur_pos + 1;
+
+ if (item_moved(&tmp_ih, &path_to_entry)) {
+ set_cpu_key_k_offset(&pos_key,
+ next_pos);
+ goto research;
+ }
+ } /* for */
+ }
+
+ /* end of directory has been reached */
+ if (item_num != B_NR_ITEMS(bh) - 1)
+ goto end;
+
+ /*
+ * item we went through is last item of node. Using right
+ * delimiting key check is it directory end
+ */
+ rkey = get_rkey(&path_to_entry, inode->i_sb);
+ if (!comp_le_keys(rkey, &MIN_KEY)) {
+ /*
+ * set pos_key to key, that is the smallest and greater
+ * that key of the last entry in the item
+ */
+ set_cpu_key_k_offset(&pos_key, next_pos);
+ continue;
+ }
+
+ /* end of directory has been reached */
+ if (COMP_SHORT_KEYS(rkey, &pos_key)) {
+ goto end;
+ }
+
+ /* directory continues in the right neighboring block */
+ set_cpu_key_k_offset(&pos_key,
+ le_key_k_offset(KEY_FORMAT_3_5, rkey));
+
+ } /* while */
+
+end:
+ ctx->pos = next_pos;
+ pathrelse(&path_to_entry);
+ reiserfs_check_path(&path_to_entry);
+out:
+ reiserfs_write_unlock(inode->i_sb);
+ return ret;
+}
+
+static int reiserfs_readdir(struct file *file, struct dir_context *ctx)
+{
+ return reiserfs_readdir_inode(file_inode(file), ctx);
+}
+
+/*
+ * compose directory item containing "." and ".." entries (entries are
+ * not aligned to 4 byte boundary)
+ */
+void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
+ __le32 par_dirid, __le32 par_objid)
+{
+ struct reiserfs_de_head *dot, *dotdot;
+
+ memset(body, 0, EMPTY_DIR_SIZE_V1);
+ dot = (struct reiserfs_de_head *)body;
+ dotdot = dot + 1;
+
+ /* direntry header of "." */
+ put_deh_offset(dot, DOT_OFFSET);
+ /* these two are from make_le_item_head, and are are LE */
+ dot->deh_dir_id = dirid;
+ dot->deh_objectid = objid;
+ dot->deh_state = 0; /* Endian safe if 0 */
+ put_deh_location(dot, EMPTY_DIR_SIZE_V1 - strlen("."));
+ mark_de_visible(dot);
+
+ /* direntry header of ".." */
+ put_deh_offset(dotdot, DOT_DOT_OFFSET);
+ /* key of ".." for the root directory */
+ /* these two are from the inode, and are are LE */
+ dotdot->deh_dir_id = par_dirid;
+ dotdot->deh_objectid = par_objid;
+ dotdot->deh_state = 0; /* Endian safe if 0 */
+ put_deh_location(dotdot, deh_location(dot) - strlen(".."));
+ mark_de_visible(dotdot);
+
+ /* copy ".." and "." */
+ memcpy(body + deh_location(dot), ".", 1);
+ memcpy(body + deh_location(dotdot), "..", 2);
+}
+
+/* compose directory item containing "." and ".." entries */
+void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
+ __le32 par_dirid, __le32 par_objid)
+{
+ struct reiserfs_de_head *dot, *dotdot;
+
+ memset(body, 0, EMPTY_DIR_SIZE);
+ dot = (struct reiserfs_de_head *)body;
+ dotdot = dot + 1;
+
+ /* direntry header of "." */
+ put_deh_offset(dot, DOT_OFFSET);
+ /* these two are from make_le_item_head, and are are LE */
+ dot->deh_dir_id = dirid;
+ dot->deh_objectid = objid;
+ dot->deh_state = 0; /* Endian safe if 0 */
+ put_deh_location(dot, EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
+ mark_de_visible(dot);
+
+ /* direntry header of ".." */
+ put_deh_offset(dotdot, DOT_DOT_OFFSET);
+ /* key of ".." for the root directory */
+ /* these two are from the inode, and are are LE */
+ dotdot->deh_dir_id = par_dirid;
+ dotdot->deh_objectid = par_objid;
+ dotdot->deh_state = 0; /* Endian safe if 0 */
+ put_deh_location(dotdot, deh_location(dot) - ROUND_UP(strlen("..")));
+ mark_de_visible(dotdot);
+
+ /* copy ".." and "." */
+ memcpy(body + deh_location(dot), ".", 1);
+ memcpy(body + deh_location(dotdot), "..", 2);
+}
Code Review / kvmfornfv.git / blobdiff