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-rw-r--r--fs/ufs/dir.c627
1 files changed, 627 insertions, 0 deletions
diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
new file mode 100644
index 00000000000..d0915fba155
--- /dev/null
+++ b/fs/ufs/dir.c
@@ -0,0 +1,627 @@
+/*
+ * linux/fs/ufs/ufs_dir.c
+ *
+ * Copyright (C) 1996
+ * Adrian Rodriguez (adrian@franklins-tower.rutgers.edu)
+ * Laboratory for Computer Science Research Computing Facility
+ * Rutgers, The State University of New Jersey
+ *
+ * swab support by Francois-Rene Rideau <fare@tunes.org> 19970406
+ *
+ * 4.4BSD (FreeBSD) support added on February 1st 1998 by
+ * Niels Kristian Bech Jensen <nkbj@image.dk> partially based
+ * on code by Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/ufs_fs.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <linux/sched.h>
+
+#include "swab.h"
+#include "util.h"
+
+#undef UFS_DIR_DEBUG
+
+#ifdef UFS_DIR_DEBUG
+#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
+#else
+#define UFSD(x)
+#endif
+
+static int
+ufs_check_dir_entry (const char *, struct inode *, struct ufs_dir_entry *,
+ struct buffer_head *, unsigned long);
+
+
+/*
+ * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure.
+ *
+ * len <= UFS_MAXNAMLEN and de != NULL are guaranteed by caller.
+ */
+static inline int ufs_match(struct super_block *sb, int len,
+ const char * const name, struct ufs_dir_entry * de)
+{
+ if (len != ufs_get_de_namlen(sb, de))
+ return 0;
+ if (!de->d_ino)
+ return 0;
+ return !memcmp(name, de->d_name, len);
+}
+
+/*
+ * This is blatantly stolen from ext2fs
+ */
+static int
+ufs_readdir (struct file * filp, void * dirent, filldir_t filldir)
+{
+ struct inode *inode = filp->f_dentry->d_inode;
+ int error = 0;
+ unsigned long offset, lblk;
+ int i, stored;
+ struct buffer_head * bh;
+ struct ufs_dir_entry * de;
+ struct super_block * sb;
+ int de_reclen;
+ unsigned flags;
+ u64 blk= 0L;
+
+ lock_kernel();
+
+ sb = inode->i_sb;
+ flags = UFS_SB(sb)->s_flags;
+
+ UFSD(("ENTER, ino %lu f_pos %lu\n", inode->i_ino, (unsigned long) filp->f_pos))
+
+ stored = 0;
+ bh = NULL;
+ offset = filp->f_pos & (sb->s_blocksize - 1);
+
+ while (!error && !stored && filp->f_pos < inode->i_size) {
+ lblk = (filp->f_pos) >> sb->s_blocksize_bits;
+ blk = ufs_frag_map(inode, lblk);
+ if (!blk || !(bh = sb_bread(sb, blk))) {
+ /* XXX - error - skip to the next block */
+ printk("ufs_readdir: "
+ "dir inode %lu has a hole at offset %lu\n",
+ inode->i_ino, (unsigned long int)filp->f_pos);
+ filp->f_pos += sb->s_blocksize - offset;
+ continue;
+ }
+
+revalidate:
+ /* If the dir block has changed since the last call to
+ * readdir(2), then we might be pointing to an invalid
+ * dirent right now. Scan from the start of the block
+ * to make sure. */
+ if (filp->f_version != inode->i_version) {
+ for (i = 0; i < sb->s_blocksize && i < offset; ) {
+ de = (struct ufs_dir_entry *)(bh->b_data + i);
+ /* It's too expensive to do a full
+ * dirent test each time round this
+ * loop, but we do have to test at
+ * least that it is non-zero. A
+ * failure will be detected in the
+ * dirent test below. */
+ de_reclen = fs16_to_cpu(sb, de->d_reclen);
+ if (de_reclen < 1)
+ break;
+ i += de_reclen;
+ }
+ offset = i;
+ filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
+ | offset;
+ filp->f_version = inode->i_version;
+ }
+
+ while (!error && filp->f_pos < inode->i_size
+ && offset < sb->s_blocksize) {
+ de = (struct ufs_dir_entry *) (bh->b_data + offset);
+ /* XXX - put in a real ufs_check_dir_entry() */
+ if ((de->d_reclen == 0) || (ufs_get_de_namlen(sb, de) == 0)) {
+ filp->f_pos = (filp->f_pos &
+ (sb->s_blocksize - 1)) +
+ sb->s_blocksize;
+ brelse(bh);
+ unlock_kernel();
+ return stored;
+ }
+ if (!ufs_check_dir_entry ("ufs_readdir", inode, de,
+ bh, offset)) {
+ /* On error, skip the f_pos to the
+ next block. */
+ filp->f_pos = (filp->f_pos |
+ (sb->s_blocksize - 1)) +
+ 1;
+ brelse (bh);
+ unlock_kernel();
+ return stored;
+ }
+ offset += fs16_to_cpu(sb, de->d_reclen);
+ if (de->d_ino) {
+ /* We might block in the next section
+ * if the data destination is
+ * currently swapped out. So, use a
+ * version stamp to detect whether or
+ * not the directory has been modified
+ * during the copy operation. */
+ unsigned long version = filp->f_version;
+ unsigned char d_type = DT_UNKNOWN;
+
+ UFSD(("filldir(%s,%u)\n", de->d_name,
+ fs32_to_cpu(sb, de->d_ino)))
+ UFSD(("namlen %u\n", ufs_get_de_namlen(sb, de)))
+
+ if ((flags & UFS_DE_MASK) == UFS_DE_44BSD)
+ d_type = de->d_u.d_44.d_type;
+ error = filldir(dirent, de->d_name,
+ ufs_get_de_namlen(sb, de), filp->f_pos,
+ fs32_to_cpu(sb, de->d_ino), d_type);
+ if (error)
+ break;
+ if (version != filp->f_version)
+ goto revalidate;
+ stored ++;
+ }
+ filp->f_pos += fs16_to_cpu(sb, de->d_reclen);
+ }
+ offset = 0;
+ brelse (bh);
+ }
+ unlock_kernel();
+ return 0;
+}
+
+/*
+ * define how far ahead to read directories while searching them.
+ */
+#define NAMEI_RA_CHUNKS 2
+#define NAMEI_RA_BLOCKS 4
+#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
+
+/*
+ * ufs_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the cache buffer in which the entry was found, and the entry
+ * itself (as a parameter - res_bh). It does NOT read the inode of the
+ * entry - you'll have to do that yourself if you want to.
+ */
+struct ufs_dir_entry * ufs_find_entry (struct dentry *dentry,
+ struct buffer_head ** res_bh)
+{
+ struct super_block * sb;
+ struct buffer_head * bh_use[NAMEI_RA_SIZE];
+ struct buffer_head * bh_read[NAMEI_RA_SIZE];
+ unsigned long offset;
+ int block, toread, i, err;
+ struct inode *dir = dentry->d_parent->d_inode;
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+
+ UFSD(("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen))
+
+ *res_bh = NULL;
+
+ sb = dir->i_sb;
+
+ if (namelen > UFS_MAXNAMLEN)
+ return NULL;
+
+ memset (bh_use, 0, sizeof (bh_use));
+ toread = 0;
+ for (block = 0; block < NAMEI_RA_SIZE; ++block) {
+ struct buffer_head * bh;
+
+ if ((block << sb->s_blocksize_bits) >= dir->i_size)
+ break;
+ bh = ufs_getfrag (dir, block, 0, &err);
+ bh_use[block] = bh;
+ if (bh && !buffer_uptodate(bh))
+ bh_read[toread++] = bh;
+ }
+
+ for (block = 0, offset = 0; offset < dir->i_size; block++) {
+ struct buffer_head * bh;
+ struct ufs_dir_entry * de;
+ char * dlimit;
+
+ if ((block % NAMEI_RA_BLOCKS) == 0 && toread) {
+ ll_rw_block (READ, toread, bh_read);
+ toread = 0;
+ }
+ bh = bh_use[block % NAMEI_RA_SIZE];
+ if (!bh) {
+ ufs_error (sb, "ufs_find_entry",
+ "directory #%lu contains a hole at offset %lu",
+ dir->i_ino, offset);
+ offset += sb->s_blocksize;
+ continue;
+ }
+ wait_on_buffer (bh);
+ if (!buffer_uptodate(bh)) {
+ /*
+ * read error: all bets are off
+ */
+ break;
+ }
+
+ de = (struct ufs_dir_entry *) bh->b_data;
+ dlimit = bh->b_data + sb->s_blocksize;
+ while ((char *) de < dlimit && offset < dir->i_size) {
+ /* this code is executed quadratically often */
+ /* do minimal checking by hand */
+ int de_len;
+
+ if ((char *) de + namelen <= dlimit &&
+ ufs_match(sb, namelen, name, de)) {
+ /* found a match -
+ just to be sure, do a full check */
+ if (!ufs_check_dir_entry("ufs_find_entry",
+ dir, de, bh, offset))
+ goto failed;
+ for (i = 0; i < NAMEI_RA_SIZE; ++i) {
+ if (bh_use[i] != bh)
+ brelse (bh_use[i]);
+ }
+ *res_bh = bh;
+ return de;
+ }
+ /* prevent looping on a bad block */
+ de_len = fs16_to_cpu(sb, de->d_reclen);
+ if (de_len <= 0)
+ goto failed;
+ offset += de_len;
+ de = (struct ufs_dir_entry *) ((char *) de + de_len);
+ }
+
+ brelse (bh);
+ if (((block + NAMEI_RA_SIZE) << sb->s_blocksize_bits ) >=
+ dir->i_size)
+ bh = NULL;
+ else
+ bh = ufs_getfrag (dir, block + NAMEI_RA_SIZE, 0, &err);
+ bh_use[block % NAMEI_RA_SIZE] = bh;
+ if (bh && !buffer_uptodate(bh))
+ bh_read[toread++] = bh;
+ }
+
+failed:
+ for (i = 0; i < NAMEI_RA_SIZE; ++i) brelse (bh_use[i]);
+ UFSD(("EXIT\n"))
+ return NULL;
+}
+
+static int
+ufs_check_dir_entry (const char *function, struct inode *dir,
+ struct ufs_dir_entry *de, struct buffer_head *bh,
+ unsigned long offset)
+{
+ struct super_block *sb = dir->i_sb;
+ const char *error_msg = NULL;
+ int rlen = fs16_to_cpu(sb, de->d_reclen);
+
+ if (rlen < UFS_DIR_REC_LEN(1))
+ error_msg = "reclen is smaller than minimal";
+ else if (rlen % 4 != 0)
+ error_msg = "reclen % 4 != 0";
+ else if (rlen < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)))
+ error_msg = "reclen is too small for namlen";
+ else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
+ error_msg = "directory entry across blocks";
+ else if (fs32_to_cpu(sb, de->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg *
+ UFS_SB(sb)->s_uspi->s_ncg))
+ error_msg = "inode out of bounds";
+
+ if (error_msg != NULL)
+ ufs_error (sb, function, "bad entry in directory #%lu, size %Lu: %s - "
+ "offset=%lu, inode=%lu, reclen=%d, namlen=%d",
+ dir->i_ino, dir->i_size, error_msg, offset,
+ (unsigned long)fs32_to_cpu(sb, de->d_ino),
+ rlen, ufs_get_de_namlen(sb, de));
+
+ return (error_msg == NULL ? 1 : 0);
+}
+
+struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct buffer_head **p)
+{
+ int err;
+ struct buffer_head *bh = ufs_bread (dir, 0, 0, &err);
+ struct ufs_dir_entry *res = NULL;
+
+ if (bh) {
+ res = (struct ufs_dir_entry *) bh->b_data;
+ res = (struct ufs_dir_entry *)((char *)res +
+ fs16_to_cpu(dir->i_sb, res->d_reclen));
+ }
+ *p = bh;
+ return res;
+}
+ino_t ufs_inode_by_name(struct inode * dir, struct dentry *dentry)
+{
+ ino_t res = 0;
+ struct ufs_dir_entry * de;
+ struct buffer_head *bh;
+
+ de = ufs_find_entry (dentry, &bh);
+ if (de) {
+ res = fs32_to_cpu(dir->i_sb, de->d_ino);
+ brelse(bh);
+ }
+ return res;
+}
+
+void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
+ struct buffer_head *bh, struct inode *inode)
+{
+ dir->i_version++;
+ de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
+ mark_buffer_dirty(bh);
+ if (IS_DIRSYNC(dir))
+ sync_dirty_buffer(bh);
+ brelse (bh);
+}
+
+/*
+ * ufs_add_entry()
+ *
+ * adds a file entry to the specified directory, using the same
+ * semantics as ufs_find_entry(). It returns NULL if it failed.
+ */
+int ufs_add_link(struct dentry *dentry, struct inode *inode)
+{
+ struct super_block * sb;
+ struct ufs_sb_private_info * uspi;
+ unsigned long offset;
+ unsigned fragoff;
+ unsigned short rec_len;
+ struct buffer_head * bh;
+ struct ufs_dir_entry * de, * de1;
+ struct inode *dir = dentry->d_parent->d_inode;
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+ int err;
+
+ UFSD(("ENTER, name %s, namelen %u\n", name, namelen))
+
+ sb = dir->i_sb;
+ uspi = UFS_SB(sb)->s_uspi;
+
+ if (!namelen)
+ return -EINVAL;
+ bh = ufs_bread (dir, 0, 0, &err);
+ if (!bh)
+ return err;
+ rec_len = UFS_DIR_REC_LEN(namelen);
+ offset = 0;
+ de = (struct ufs_dir_entry *) bh->b_data;
+ while (1) {
+ if ((char *)de >= UFS_SECTOR_SIZE + bh->b_data) {
+ fragoff = offset & ~uspi->s_fmask;
+ if (fragoff != 0 && fragoff != UFS_SECTOR_SIZE)
+ ufs_error (sb, "ufs_add_entry", "internal error"
+ " fragoff %u", fragoff);
+ if (!fragoff) {
+ brelse (bh);
+ bh = ufs_bread (dir, offset >> sb->s_blocksize_bits, 1, &err);
+ if (!bh)
+ return err;
+ }
+ if (dir->i_size <= offset) {
+ if (dir->i_size == 0) {
+ brelse(bh);
+ return -ENOENT;
+ }
+ de = (struct ufs_dir_entry *) (bh->b_data + fragoff);
+ de->d_ino = 0;
+ de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE);
+ ufs_set_de_namlen(sb, de, 0);
+ dir->i_size = offset + UFS_SECTOR_SIZE;
+ mark_inode_dirty(dir);
+ } else {
+ de = (struct ufs_dir_entry *) bh->b_data;
+ }
+ }
+ if (!ufs_check_dir_entry ("ufs_add_entry", dir, de, bh, offset)) {
+ brelse (bh);
+ return -ENOENT;
+ }
+ if (ufs_match(sb, namelen, name, de)) {
+ brelse (bh);
+ return -EEXIST;
+ }
+ if (de->d_ino == 0 && fs16_to_cpu(sb, de->d_reclen) >= rec_len)
+ break;
+
+ if (fs16_to_cpu(sb, de->d_reclen) >=
+ UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)) + rec_len)
+ break;
+ offset += fs16_to_cpu(sb, de->d_reclen);
+ de = (struct ufs_dir_entry *) ((char *) de + fs16_to_cpu(sb, de->d_reclen));
+ }
+
+ if (de->d_ino) {
+ de1 = (struct ufs_dir_entry *) ((char *) de +
+ UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+ de1->d_reclen =
+ cpu_to_fs16(sb, fs16_to_cpu(sb, de->d_reclen) -
+ UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+ de->d_reclen =
+ cpu_to_fs16(sb, UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+ de = de1;
+ }
+ de->d_ino = 0;
+ ufs_set_de_namlen(sb, de, namelen);
+ memcpy (de->d_name, name, namelen + 1);
+ de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+ ufs_set_de_type(sb, de, inode->i_mode);
+ mark_buffer_dirty(bh);
+ if (IS_DIRSYNC(dir))
+ sync_dirty_buffer(bh);
+ brelse (bh);
+ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+ dir->i_version++;
+ mark_inode_dirty(dir);
+
+ UFSD(("EXIT\n"))
+ return 0;
+}
+
+/*
+ * ufs_delete_entry deletes a directory entry by merging it with the
+ * previous entry.
+ */
+int ufs_delete_entry (struct inode * inode, struct ufs_dir_entry * dir,
+ struct buffer_head * bh )
+
+{
+ struct super_block * sb;
+ struct ufs_dir_entry * de, * pde;
+ unsigned i;
+
+ UFSD(("ENTER\n"))
+
+ sb = inode->i_sb;
+ i = 0;
+ pde = NULL;
+ de = (struct ufs_dir_entry *) bh->b_data;
+
+ UFSD(("ino %u, reclen %u, namlen %u, name %s\n",
+ fs32_to_cpu(sb, de->d_ino),
+ fs16to_cpu(sb, de->d_reclen),
+ ufs_get_de_namlen(sb, de), de->d_name))
+
+ while (i < bh->b_size) {
+ if (!ufs_check_dir_entry ("ufs_delete_entry", inode, de, bh, i)) {
+ brelse(bh);
+ return -EIO;
+ }
+ if (de == dir) {
+ if (pde)
+ fs16_add(sb, &pde->d_reclen,
+ fs16_to_cpu(sb, dir->d_reclen));
+ dir->d_ino = 0;
+ inode->i_version++;
+ inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+ mark_inode_dirty(inode);
+ mark_buffer_dirty(bh);
+ if (IS_DIRSYNC(inode))
+ sync_dirty_buffer(bh);
+ brelse(bh);
+ UFSD(("EXIT\n"))
+ return 0;
+ }
+ i += fs16_to_cpu(sb, de->d_reclen);
+ if (i == UFS_SECTOR_SIZE) pde = NULL;
+ else pde = de;
+ de = (struct ufs_dir_entry *)
+ ((char *) de + fs16_to_cpu(sb, de->d_reclen));
+ if (i == UFS_SECTOR_SIZE && de->d_reclen == 0)
+ break;
+ }
+ UFSD(("EXIT\n"))
+ brelse(bh);
+ return -ENOENT;
+}
+
+int ufs_make_empty(struct inode * inode, struct inode *dir)
+{
+ struct super_block * sb = dir->i_sb;
+ struct buffer_head * dir_block;
+ struct ufs_dir_entry * de;
+ int err;
+
+ dir_block = ufs_bread (inode, 0, 1, &err);
+ if (!dir_block)
+ return err;
+
+ inode->i_blocks = sb->s_blocksize / UFS_SECTOR_SIZE;
+ de = (struct ufs_dir_entry *) dir_block->b_data;
+ de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+ ufs_set_de_type(sb, de, inode->i_mode);
+ ufs_set_de_namlen(sb, de, 1);
+ de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1));
+ strcpy (de->d_name, ".");
+ de = (struct ufs_dir_entry *)
+ ((char *)de + fs16_to_cpu(sb, de->d_reclen));
+ de->d_ino = cpu_to_fs32(sb, dir->i_ino);
+ ufs_set_de_type(sb, de, dir->i_mode);
+ de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE - UFS_DIR_REC_LEN(1));
+ ufs_set_de_namlen(sb, de, 2);
+ strcpy (de->d_name, "..");
+ mark_buffer_dirty(dir_block);
+ brelse (dir_block);
+ mark_inode_dirty(inode);
+ return 0;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+int ufs_empty_dir (struct inode * inode)
+{
+ struct super_block * sb;
+ unsigned long offset;
+ struct buffer_head * bh;
+ struct ufs_dir_entry * de, * de1;
+ int err;
+
+ sb = inode->i_sb;
+
+ if (inode->i_size < UFS_DIR_REC_LEN(1) + UFS_DIR_REC_LEN(2) ||
+ !(bh = ufs_bread (inode, 0, 0, &err))) {
+ ufs_warning (inode->i_sb, "empty_dir",
+ "bad directory (dir #%lu) - no data block",
+ inode->i_ino);
+ return 1;
+ }
+ de = (struct ufs_dir_entry *) bh->b_data;
+ de1 = (struct ufs_dir_entry *)
+ ((char *)de + fs16_to_cpu(sb, de->d_reclen));
+ if (fs32_to_cpu(sb, de->d_ino) != inode->i_ino || de1->d_ino == 0 ||
+ strcmp (".", de->d_name) || strcmp ("..", de1->d_name)) {
+ ufs_warning (inode->i_sb, "empty_dir",
+ "bad directory (dir #%lu) - no `.' or `..'",
+ inode->i_ino);
+ return 1;
+ }
+ offset = fs16_to_cpu(sb, de->d_reclen) + fs16_to_cpu(sb, de1->d_reclen);
+ de = (struct ufs_dir_entry *)
+ ((char *)de1 + fs16_to_cpu(sb, de1->d_reclen));
+ while (offset < inode->i_size ) {
+ if (!bh || (void *) de >= (void *) (bh->b_data + sb->s_blocksize)) {
+ brelse (bh);
+ bh = ufs_bread (inode, offset >> sb->s_blocksize_bits, 1, &err);
+ if (!bh) {
+ ufs_error (sb, "empty_dir",
+ "directory #%lu contains a hole at offset %lu",
+ inode->i_ino, offset);
+ offset += sb->s_blocksize;
+ continue;
+ }
+ de = (struct ufs_dir_entry *) bh->b_data;
+ }
+ if (!ufs_check_dir_entry ("empty_dir", inode, de, bh, offset)) {
+ brelse (bh);
+ return 1;
+ }
+ if (de->d_ino) {
+ brelse (bh);
+ return 0;
+ }
+ offset += fs16_to_cpu(sb, de->d_reclen);
+ de = (struct ufs_dir_entry *)
+ ((char *)de + fs16_to_cpu(sb, de->d_reclen));
+ }
+ brelse (bh);
+ return 1;
+}
+
+struct file_operations ufs_dir_operations = {
+ .read = generic_read_dir,
+ .readdir = ufs_readdir,
+ .fsync = file_fsync,
+};
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-19 21:13:08 +0000