1 files changed, 328 insertions, 0 deletions

diff --git a/fs/freevxfs/vxfs_lookup.c b/fs/freevxfs/vxfs_lookup.c
new file mode 100644
index 000000000000..506ae251d2c0
--- /dev/null
+++ b/fs/freevxfs/vxfs_lookup.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright (c) 2000-2001 Christoph Hellwig.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL").
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * Veritas filesystem driver - lookup and other directory related code.
+ */
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+
+#include "vxfs.h"
+#include "vxfs_dir.h"
+#include "vxfs_inode.h"
+#include "vxfs_extern.h"
+
+/*
+ * Number of VxFS blocks per page.
+ */
+#define VXFS_BLOCK_PER_PAGE(sbp)  ((PAGE_CACHE_SIZE / (sbp)->s_blocksize))
+
+
+static struct dentry *  vxfs_lookup(struct inode *, struct dentry *, struct nameidata *);
+static int              vxfs_readdir(struct file *, void *, filldir_t);
+
+struct inode_operations vxfs_dir_inode_ops = {
+        .lookup =               vxfs_lookup,
+};
+
+struct file_operations vxfs_dir_operations = {
+        .readdir =              vxfs_readdir,
+};
+
+ 
+static __inline__ u_long
+dir_pages(struct inode *inode)
+{
+        return (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+}
+ 
+static __inline__ u_long
+dir_blocks(struct inode *ip)
+{
+        u_long                  bsize = ip->i_sb->s_blocksize;
+        return (ip->i_size + bsize - 1) & ~(bsize - 1);
+}
+
+/*
+ * NOTE! unlike strncmp, vxfs_match returns 1 for success, 0 for failure.
+ *
+ * len <= VXFS_NAMELEN and de != NULL are guaranteed by caller.
+ */
+static __inline__ int
+vxfs_match(int len, const char * const name, struct vxfs_direct *de)
+{
+        if (len != de->d_namelen)
+                return 0;
+        if (!de->d_ino)
+                return 0;
+        return !memcmp(name, de->d_name, len);
+}
+
+static __inline__ struct vxfs_direct *
+vxfs_next_entry(struct vxfs_direct *de)
+{
+        return ((struct vxfs_direct *)((char*)de + de->d_reclen));
+}
+
+/**
+ * vxfs_find_entry - find a mathing directory entry for a dentry
+ * @ip:         directory inode
+ * @dp:         dentry for which we want to find a direct
+ * @ppp:        gets filled with the page the return value sits in
+ *
+ * Description:
+ *   vxfs_find_entry finds a &struct vxfs_direct for the VFS directory
+ *   cache entry @dp.  @ppp will be filled with the page the return
+ *   value resides in.
+ *
+ * Returns:
+ *   The wanted direct on success, else a NULL pointer.
+ */
+static struct vxfs_direct *
+vxfs_find_entry(struct inode *ip, struct dentry *dp, struct page **ppp)
+{
+        u_long                          npages, page, nblocks, pblocks, block;
+        u_long                          bsize = ip->i_sb->s_blocksize;
+        const char                      *name = dp->d_name.name;
+        int                             namelen = dp->d_name.len;
+
+        npages = dir_pages(ip);
+        nblocks = dir_blocks(ip);
+        pblocks = VXFS_BLOCK_PER_PAGE(ip->i_sb);
+        
+        for (page = 0; page < npages; page++) {
+                caddr_t                 kaddr;
+                struct page             *pp;
+
+                pp = vxfs_get_page(ip->i_mapping, page);
+                if (IS_ERR(pp))
+                        continue;
+                kaddr = (caddr_t)page_address(pp);
+
+                for (block = 0; block <= nblocks && block <= pblocks; block++) {
+                        caddr_t                 baddr, limit;
+                        struct vxfs_dirblk      *dbp;
+                        struct vxfs_direct      *de;
+
+                        baddr = kaddr + (block * bsize);
+                        limit = baddr + bsize - VXFS_DIRLEN(1);
+                        
+                        dbp = (struct vxfs_dirblk *)baddr;
+                        de = (struct vxfs_direct *)(baddr + VXFS_DIRBLKOV(dbp));
+
+                        for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) {
+                                if (!de->d_reclen)
+                                        break;
+                                if (!de->d_ino)
+                                        continue;
+                                if (vxfs_match(namelen, name, de)) {
+                                        *ppp = pp;
+                                        return (de);
+                                }
+                        }
+                }
+                vxfs_put_page(pp);
+        }
+
+        return NULL;
+}
+
+/**
+ * vxfs_inode_by_name - find inode number for dentry
+ * @dip:        directory to search in
+ * @dp:         dentry we seach for
+ *
+ * Description:
+ *   vxfs_inode_by_name finds out the inode number of
+ *   the path component described by @dp in @dip.
+ *
+ * Returns:
+ *   The wanted inode number on success, else Zero.
+ */
+static ino_t
+vxfs_inode_by_name(struct inode *dip, struct dentry *dp)
+{
+        struct vxfs_direct              *de;
+        struct page                     *pp;
+        ino_t                           ino = 0;
+
+        de = vxfs_find_entry(dip, dp, &pp);
+        if (de) {
+                ino = de->d_ino;
+                kunmap(pp);
+                page_cache_release(pp);
+        }
+        
+        return (ino);
+}
+
+/**
+ * vxfs_lookup - lookup pathname component
+ * @dip:        dir in which we lookup
+ * @dp:         dentry we lookup
+ * @nd:         lookup nameidata
+ *
+ * Description:
+ *   vxfs_lookup tries to lookup the pathname component described
+ *   by @dp in @dip.
+ *
+ * Returns:
+ *   A NULL-pointer on success, else an negative error code encoded
+ *   in the return pointer.
+ */
+static struct dentry *
+vxfs_lookup(struct inode *dip, struct dentry *dp, struct nameidata *nd)
+{
+        struct inode            *ip = NULL;
+        ino_t                   ino;
+                         
+        if (dp->d_name.len > VXFS_NAMELEN)
+                return ERR_PTR(-ENAMETOOLONG);
+                                 
+        lock_kernel();
+        ino = vxfs_inode_by_name(dip, dp);
+        if (ino) {
+                ip = iget(dip->i_sb, ino);
+                if (!ip) {
+                        unlock_kernel();
+                        return ERR_PTR(-EACCES);
+                }
+        }
+        unlock_kernel();
+        d_add(dp, ip);
+        return NULL;
+}
+
+/**
+ * vxfs_readdir - read a directory
+ * @fp:         the directory to read
+ * @retp:       return buffer
+ * @filler:     filldir callback
+ *
+ * Description:
+ *   vxfs_readdir fills @retp with directory entries from @fp
+ *   using the VFS supplied callback @filler.
+ *
+ * Returns:
+ *   Zero.
+ */
+static int
+vxfs_readdir(struct file *fp, void *retp, filldir_t filler)
+{
+        struct inode            *ip = fp->f_dentry->d_inode;
+        struct super_block      *sbp = ip->i_sb;
+        u_long                  bsize = sbp->s_blocksize;
+        u_long                  page, npages, block, pblocks, nblocks, offset;
+        loff_t                  pos;
+
+        switch ((long)fp->f_pos) {
+        case 0:
+                if (filler(retp, ".", 1, fp->f_pos, ip->i_ino, DT_DIR) < 0)
+                        goto out;
+                fp->f_pos++;
+                /* fallthrough */
+        case 1:
+                if (filler(retp, "..", 2, fp->f_pos, VXFS_INO(ip)->vii_dotdot, DT_DIR) < 0)
+                        goto out;
+                fp->f_pos++;
+                /* fallthrough */
+        }
+
+        pos = fp->f_pos - 2;
+        
+        if (pos > VXFS_DIRROUND(ip->i_size)) {
+                unlock_kernel();
+                return 0;
+        }
+
+        npages = dir_pages(ip);
+        nblocks = dir_blocks(ip);
+        pblocks = VXFS_BLOCK_PER_PAGE(sbp);
+
+        page = pos >> PAGE_CACHE_SHIFT;
+        offset = pos & ~PAGE_CACHE_MASK;
+        block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks;
+
+        for (; page < npages; page++, block = 0) {
+                caddr_t                 kaddr;
+                struct page             *pp;
+
+                pp = vxfs_get_page(ip->i_mapping, page);
+                if (IS_ERR(pp))
+                        continue;
+                kaddr = (caddr_t)page_address(pp);
+
+                for (; block <= nblocks && block <= pblocks; block++) {
+                        caddr_t                 baddr, limit;
+                        struct vxfs_dirblk      *dbp;
+                        struct vxfs_direct      *de;
+
+                        baddr = kaddr + (block * bsize);
+                        limit = baddr + bsize - VXFS_DIRLEN(1);
+        
+                        dbp = (struct vxfs_dirblk *)baddr;
+                        de = (struct vxfs_direct *)
+                                (offset ?
+                                 (kaddr + offset) :
+                                 (baddr + VXFS_DIRBLKOV(dbp)));
+
+                        for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) {
+                                int     over;
+
+                                if (!de->d_reclen)
+                                        break;
+                                if (!de->d_ino)
+                                        continue;
+
+                                offset = (caddr_t)de - kaddr;
+                                over = filler(retp, de->d_name, de->d_namelen,
+                                        ((page << PAGE_CACHE_SHIFT) | offset) + 2,
+                                        de->d_ino, DT_UNKNOWN);
+                                if (over) {
+                                        vxfs_put_page(pp);
+                                        goto done;
+                                }
+                        }
+                        offset = 0;
+                }
+                vxfs_put_page(pp);
+                offset = 0;
+        }
+
+done:
+        fp->f_pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2;
+out:
+        unlock_kernel();
+        return 0;
+}