[readdir] convert efs
authorAl Viro <viro@zeniv.linux.org.uk>
Thu, 16 May 2013 05:41:10 +0000 (01:41 -0400)
committerAl Viro <viro@zeniv.linux.org.uk>
Sat, 29 Jun 2013 08:56:31 +0000 (12:56 +0400)
* sanity checks belong before risky operation, not after it
* don't quit as soon as we'd found an entry

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
fs/efs/dir.c

index 055a9e9ca747fb4d0cbae33c14930cdd8cbe4cb7..b72307ccdf7afc08c2062741a585b971d0e99a15 100644 (file)
@@ -7,40 +7,38 @@
 #include <linux/buffer_head.h>
 #include "efs.h"
 
-static int efs_readdir(struct file *, void *, filldir_t);
+static int efs_readdir(struct file *, struct dir_context *);
 
 const struct file_operations efs_dir_operations = {
        .llseek         = generic_file_llseek,
        .read           = generic_read_dir,
-       .readdir        = efs_readdir,
+       .iterate        = efs_readdir,
 };
 
 const struct inode_operations efs_dir_inode_operations = {
        .lookup         = efs_lookup,
 };
 
-static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {
-       struct inode *inode = file_inode(filp);
-       struct buffer_head *bh;
-
-       struct efs_dir          *dirblock;
-       struct efs_dentry       *dirslot;
-       efs_ino_t               inodenum;
+static int efs_readdir(struct file *file, struct dir_context *ctx)
+{
+       struct inode *inode = file_inode(file);
        efs_block_t             block;
-       int                     slot, namelen;
-       char                    *nameptr;
+       int                     slot;
 
        if (inode->i_size & (EFS_DIRBSIZE-1))
                printk(KERN_WARNING "EFS: WARNING: readdir(): directory size not a multiple of EFS_DIRBSIZE\n");
 
        /* work out where this entry can be found */
-       block = filp->f_pos >> EFS_DIRBSIZE_BITS;
+       block = ctx->pos >> EFS_DIRBSIZE_BITS;
 
        /* each block contains at most 256 slots */
-       slot  = filp->f_pos & 0xff;
+       slot  = ctx->pos & 0xff;
 
        /* look at all blocks */
        while (block < inode->i_blocks) {
+               struct efs_dir          *dirblock;
+               struct buffer_head *bh;
+
                /* read the dir block */
                bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
 
@@ -57,11 +55,14 @@ static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {
                        break;
                }
 
-               while (slot < dirblock->slots) {
-                       if (dirblock->space[slot] == 0) {
-                               slot++;
+               for (; slot < dirblock->slots; slot++) {
+                       struct efs_dentry *dirslot;
+                       efs_ino_t inodenum;
+                       const char *nameptr;
+                       int namelen;
+
+                       if (dirblock->space[slot] == 0)
                                continue;
-                       }
 
                        dirslot  = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
 
@@ -72,39 +73,29 @@ static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {
 #ifdef DEBUG
                        printk(KERN_DEBUG "EFS: readdir(): block %d slot %d/%d: inode %u, name \"%s\", namelen %u\n", block, slot, dirblock->slots-1, inodenum, nameptr, namelen);
 #endif
-                       if (namelen > 0) {
-                               /* found the next entry */
-                               filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
-
-                               /* copy filename and data in dirslot */
-                               filldir(dirent, nameptr, namelen, filp->f_pos, inodenum, DT_UNKNOWN);
-
-                               /* sanity check */
-                               if (nameptr - (char *) dirblock + namelen > EFS_DIRBSIZE) {
-                                       printk(KERN_WARNING "EFS: directory entry %d exceeds directory block\n", slot);
-                                       slot++;
-                                       continue;
-                               }
-
-                               /* store position of next slot */
-                               if (++slot == dirblock->slots) {
-                                       slot = 0;
-                                       block++;
-                               }
+                       if (!namelen)
+                               continue;
+                       /* found the next entry */
+                       ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;
+
+                       /* sanity check */
+                       if (nameptr - (char *) dirblock + namelen > EFS_DIRBSIZE) {
+                               printk(KERN_WARNING "EFS: directory entry %d exceeds directory block\n", slot);
+                               continue;
+                       }
+
+                       /* copy filename and data in dirslot */
+                       if (!dir_emit(ctx, nameptr, namelen, inodenum, DT_UNKNOWN)) {
                                brelse(bh);
-                               filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
-                               goto out;
+                               return 0;
                        }
-                       slot++;
                }
                brelse(bh);
 
                slot = 0;
                block++;
        }
-
-       filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;
-out:
+       ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;
        return 0;
 }