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-rw-r--r--fs/qnx4/namei.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/fs/qnx4/namei.c b/fs/qnx4/namei.c
new file mode 100644
index 000000000000..4af4951d7f54
--- /dev/null
+++ b/fs/qnx4/namei.c
@@ -0,0 +1,249 @@
+/*
+ * QNX4 file system, Linux implementation.
+ *
+ * Version : 0.2.1
+ *
+ * Using parts of the xiafs filesystem.
+ *
+ * History :
+ *
+ * 01-06-1998 by Richard Frowijn : first release.
+ * 21-06-1998 by Frank Denis : dcache support, fixed error codes.
+ * 04-07-1998 by Frank Denis : first step for rmdir/unlink.
+ */
+
+#include <linux/config.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/qnx4_fs.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/fcntl.h>
+#include <linux/errno.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+
+
+/*
+ * check if the filename is correct. For some obscure reason, qnx writes a
+ * new file twice in the directory entry, first with all possible options at 0
+ * and for a second time the way it is, they want us not to access the qnx
+ * filesystem when whe are using linux.
+ */
+static int qnx4_match(int len, const char *name,
+ struct buffer_head *bh, unsigned long *offset)
+{
+ struct qnx4_inode_entry *de;
+ int namelen, thislen;
+
+ if (bh == NULL) {
+ printk("qnx4: matching unassigned buffer !\n");
+ return 0;
+ }
+ de = (struct qnx4_inode_entry *) (bh->b_data + *offset);
+ *offset += QNX4_DIR_ENTRY_SIZE;
+ if ((de->di_status & QNX4_FILE_LINK) != 0) {
+ namelen = QNX4_NAME_MAX;
+ } else {
+ namelen = QNX4_SHORT_NAME_MAX;
+ }
+ /* "" means "." ---> so paths like "/usr/lib//libc.a" work */
+ if (!len && (de->di_fname[0] == '.') && (de->di_fname[1] == '\0')) {
+ return 1;
+ }
+ thislen = strlen( de->di_fname );
+ if ( thislen > namelen )
+ thislen = namelen;
+ if (len != thislen) {
+ return 0;
+ }
+ if (strncmp(name, de->di_fname, len) == 0) {
+ if ((de->di_status & (QNX4_FILE_USED|QNX4_FILE_LINK)) != 0) {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static struct buffer_head *qnx4_find_entry(int len, struct inode *dir,
+ const char *name, struct qnx4_inode_entry **res_dir, int *ino)
+{
+ unsigned long block, offset, blkofs;
+ struct buffer_head *bh;
+
+ *res_dir = NULL;
+ if (!dir->i_sb) {
+ printk("qnx4: no superblock on dir.\n");
+ return NULL;
+ }
+ bh = NULL;
+ block = offset = blkofs = 0;
+ while (blkofs * QNX4_BLOCK_SIZE + offset < dir->i_size) {
+ if (!bh) {
+ bh = qnx4_bread(dir, blkofs, 0);
+ if (!bh) {
+ blkofs++;
+ continue;
+ }
+ }
+ *res_dir = (struct qnx4_inode_entry *) (bh->b_data + offset);
+ if (qnx4_match(len, name, bh, &offset)) {
+ block = qnx4_block_map( dir, blkofs );
+ *ino = block * QNX4_INODES_PER_BLOCK +
+ (offset / QNX4_DIR_ENTRY_SIZE) - 1;
+ return bh;
+ }
+ if (offset < bh->b_size) {
+ continue;
+ }
+ brelse(bh);
+ bh = NULL;
+ offset = 0;
+ blkofs++;
+ }
+ brelse(bh);
+ *res_dir = NULL;
+ return NULL;
+}
+
+struct dentry * qnx4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+ int ino;
+ struct qnx4_inode_entry *de;
+ struct qnx4_link_info *lnk;
+ struct buffer_head *bh;
+ const char *name = dentry->d_name.name;
+ int len = dentry->d_name.len;
+ struct inode *foundinode = NULL;
+
+ lock_kernel();
+ if (!(bh = qnx4_find_entry(len, dir, name, &de, &ino)))
+ goto out;
+ /* The entry is linked, let's get the real info */
+ if ((de->di_status & QNX4_FILE_LINK) == QNX4_FILE_LINK) {
+ lnk = (struct qnx4_link_info *) de;
+ ino = (le32_to_cpu(lnk->dl_inode_blk) - 1) *
+ QNX4_INODES_PER_BLOCK +
+ lnk->dl_inode_ndx;
+ }
+ brelse(bh);
+
+ if ((foundinode = iget(dir->i_sb, ino)) == NULL) {
+ unlock_kernel();
+ QNX4DEBUG(("qnx4: lookup->iget -> NULL\n"));
+ return ERR_PTR(-EACCES);
+ }
+out:
+ unlock_kernel();
+ d_add(dentry, foundinode);
+
+ return NULL;
+}
+
+#ifdef CONFIG_QNX4FS_RW
+int qnx4_create(struct inode *dir, struct dentry *dentry, int mode,
+ struct nameidata *nd)
+{
+ QNX4DEBUG(("qnx4: qnx4_create\n"));
+ if (dir == NULL) {
+ return -ENOENT;
+ }
+ return -ENOSPC;
+}
+
+int qnx4_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct buffer_head *bh;
+ struct qnx4_inode_entry *de;
+ struct inode *inode;
+ int retval;
+ int ino;
+
+ QNX4DEBUG(("qnx4: qnx4_rmdir [%s]\n", dentry->d_name.name));
+ lock_kernel();
+ bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name,
+ &de, &ino);
+ if (bh == NULL) {
+ unlock_kernel();
+ return -ENOENT;
+ }
+ inode = dentry->d_inode;
+ if (inode->i_ino != ino) {
+ retval = -EIO;
+ goto end_rmdir;
+ }
+#if 0
+ if (!empty_dir(inode)) {
+ retval = -ENOTEMPTY;
+ goto end_rmdir;
+ }
+#endif
+ if (inode->i_nlink != 2) {
+ QNX4DEBUG(("empty directory has nlink!=2 (%d)\n", inode->i_nlink));
+ }
+ QNX4DEBUG(("qnx4: deleting directory\n"));
+ de->di_status = 0;
+ memset(de->di_fname, 0, sizeof de->di_fname);
+ de->di_mode = 0;
+ mark_buffer_dirty(bh);
+ inode->i_nlink = 0;
+ mark_inode_dirty(inode);
+ inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
+ dir->i_nlink--;
+ mark_inode_dirty(dir);
+ retval = 0;
+
+ end_rmdir:
+ brelse(bh);
+
+ unlock_kernel();
+ return retval;
+}
+
+int qnx4_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct buffer_head *bh;
+ struct qnx4_inode_entry *de;
+ struct inode *inode;
+ int retval;
+ int ino;
+
+ QNX4DEBUG(("qnx4: qnx4_unlink [%s]\n", dentry->d_name.name));
+ lock_kernel();
+ bh = qnx4_find_entry(dentry->d_name.len, dir, dentry->d_name.name,
+ &de, &ino);
+ if (bh == NULL) {
+ unlock_kernel();
+ return -ENOENT;
+ }
+ inode = dentry->d_inode;
+ if (inode->i_ino != ino) {
+ retval = -EIO;
+ goto end_unlink;
+ }
+ retval = -EPERM;
+ if (!inode->i_nlink) {
+ QNX4DEBUG(("Deleting nonexistent file (%s:%lu), %d\n",
+ inode->i_sb->s_id,
+ inode->i_ino, inode->i_nlink));
+ inode->i_nlink = 1;
+ }
+ de->di_status = 0;
+ memset(de->di_fname, 0, sizeof de->di_fname);
+ de->di_mode = 0;
+ mark_buffer_dirty(bh);
+ dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
+ mark_inode_dirty(dir);
+ inode->i_nlink--;
+ inode->i_ctime = dir->i_ctime;
+ mark_inode_dirty(inode);
+ retval = 0;
+
+end_unlink:
+ unlock_kernel();
+ brelse(bh);
+
+ return retval;
+}
+#endif
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