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-rw-r--r--fs/affs/dir.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/fs/affs/dir.c b/fs/affs/dir.c
new file mode 100644
index 0000000..548efd0
--- /dev/null
+++ b/fs/affs/dir.c
@@ -0,0 +1,155 @@
+/*
+ * linux/fs/affs/dir.c
+ *
+ * (c) 1996 Hans-Joachim Widmaier - Rewritten
+ *
+ * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
+ *
+ * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
+ *
+ * (C) 1991 Linus Torvalds - minix filesystem
+ *
+ * affs directory handling functions
+ *
+ */
+
+#include "affs.h"
+
+static int affs_readdir(struct file *, void *, filldir_t);
+
+struct file_operations affs_dir_operations = {
+ .read = generic_read_dir,
+ .readdir = affs_readdir,
+ .fsync = file_fsync,
+};
+
+/*
+ * directories can handle most operations...
+ */
+struct inode_operations affs_dir_inode_operations = {
+ .create = affs_create,
+ .lookup = affs_lookup,
+ .link = affs_link,
+ .unlink = affs_unlink,
+ .symlink = affs_symlink,
+ .mkdir = affs_mkdir,
+ .rmdir = affs_rmdir,
+ .rename = affs_rename,
+ .setattr = affs_notify_change,
+};
+
+static int
+affs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct super_block *sb = inode->i_sb;
+ struct buffer_head *dir_bh;
+ struct buffer_head *fh_bh;
+ unsigned char *name;
+ int namelen;
+ u32 i;
+ int hash_pos;
+ int chain_pos;
+ u32 f_pos;
+ u32 ino;
+ int stored;
+ int res;
+
+ pr_debug("AFFS: readdir(ino=%lu,f_pos=%lx)\n",inode->i_ino,(unsigned long)filp->f_pos);
+
+ stored = 0;
+ res = -EIO;
+ dir_bh = NULL;
+ fh_bh = NULL;
+ f_pos = filp->f_pos;
+
+ if (f_pos == 0) {
+ filp->private_data = (void *)0;
+ if (filldir(dirent, ".", 1, f_pos, inode->i_ino, DT_DIR) < 0)
+ return 0;
+ filp->f_pos = f_pos = 1;
+ stored++;
+ }
+ if (f_pos == 1) {
+ if (filldir(dirent, "..", 2, f_pos, parent_ino(filp->f_dentry), DT_DIR) < 0)
+ return stored;
+ filp->f_pos = f_pos = 2;
+ stored++;
+ }
+
+ affs_lock_dir(inode);
+ chain_pos = (f_pos - 2) & 0xffff;
+ hash_pos = (f_pos - 2) >> 16;
+ if (chain_pos == 0xffff) {
+ affs_warning(sb, "readdir", "More than 65535 entries in chain");
+ chain_pos = 0;
+ hash_pos++;
+ filp->f_pos = ((hash_pos << 16) | chain_pos) + 2;
+ }
+ dir_bh = affs_bread(sb, inode->i_ino);
+ if (!dir_bh)
+ goto readdir_out;
+
+ /* If the directory hasn't changed since the last call to readdir(),
+ * we can jump directly to where we left off.
+ */
+ ino = (u32)(long)filp->private_data;
+ if (ino && filp->f_version == inode->i_version) {
+ pr_debug("AFFS: readdir() left off=%d\n", ino);
+ goto inside;
+ }
+
+ ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
+ for (i = 0; ino && i < chain_pos; i++) {
+ fh_bh = affs_bread(sb, ino);
+ if (!fh_bh) {
+ affs_error(sb, "readdir","Cannot read block %d", i);
+ goto readdir_out;
+ }
+ ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
+ affs_brelse(fh_bh);
+ fh_bh = NULL;
+ }
+ if (ino)
+ goto inside;
+ hash_pos++;
+
+ for (; hash_pos < AFFS_SB(sb)->s_hashsize; hash_pos++) {
+ ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
+ if (!ino)
+ continue;
+ f_pos = (hash_pos << 16) + 2;
+inside:
+ do {
+ fh_bh = affs_bread(sb, ino);
+ if (!fh_bh) {
+ affs_error(sb, "readdir","Cannot read block %d", ino);
+ goto readdir_done;
+ }
+
+ namelen = min(AFFS_TAIL(sb, fh_bh)->name[0], (u8)30);
+ name = AFFS_TAIL(sb, fh_bh)->name + 1;
+ pr_debug("AFFS: readdir(): filldir(\"%.*s\", ino=%u), hash=%d, f_pos=%x\n",
+ namelen, name, ino, hash_pos, f_pos);
+ if (filldir(dirent, name, namelen, f_pos, ino, DT_UNKNOWN) < 0)
+ goto readdir_done;
+ stored++;
+ f_pos++;
+ ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
+ affs_brelse(fh_bh);
+ fh_bh = NULL;
+ } while (ino);
+ }
+readdir_done:
+ filp->f_pos = f_pos;
+ filp->f_version = inode->i_version;
+ filp->private_data = (void *)(long)ino;
+ res = stored;
+
+readdir_out:
+ affs_brelse(dir_bh);
+ affs_brelse(fh_bh);
+ affs_unlock_dir(inode);
+ pr_debug("AFFS: readdir()=%d\n", stored);
+ return res;
+}
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