1 files changed, 704 insertions, 0 deletions

diff --git a/fs/coda/dir.c b/fs/coda/dir.c
new file mode 100644
index 00000000000..2391766e9c7
--- /dev/null
+++ b/fs/coda/dir.c
@@ -0,0 +1,704 @@
+
+/*
+ * Directory operations for Coda filesystem
+ * Original version: (C) 1996 P. Braam and M. Callahan
+ * Rewritten for Linux 2.1. (C) 1997 Carnegie Mellon University
+ * 
+ * Carnegie Mellon encourages users to contribute improvements to
+ * the Coda project. Contact Peter Braam (coda@cs.cmu.edu).
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/smp_lock.h>
+
+#include <asm/uaccess.h>
+
+#include <linux/coda.h>
+#include <linux/coda_linux.h>
+#include <linux/coda_psdev.h>
+#include <linux/coda_fs_i.h>
+#include <linux/coda_cache.h>
+#include <linux/coda_proc.h>
+
+/* dir inode-ops */
+static int coda_create(struct inode *dir, struct dentry *new, int mode, struct nameidata *nd);
+static struct dentry *coda_lookup(struct inode *dir, struct dentry *target, struct nameidata *nd);
+static int coda_link(struct dentry *old_dentry, struct inode *dir_inode, 
+		     struct dentry *entry);
+static int coda_unlink(struct inode *dir_inode, struct dentry *entry);
+static int coda_symlink(struct inode *dir_inode, struct dentry *entry,
+			const char *symname);
+static int coda_mkdir(struct inode *dir_inode, struct dentry *entry, int mode);
+static int coda_rmdir(struct inode *dir_inode, struct dentry *entry);
+static int coda_rename(struct inode *old_inode, struct dentry *old_dentry, 
+                       struct inode *new_inode, struct dentry *new_dentry);
+
+/* dir file-ops */
+static int coda_readdir(struct file *file, void *dirent, filldir_t filldir);
+
+/* dentry ops */
+static int coda_dentry_revalidate(struct dentry *de, struct nameidata *nd);
+static int coda_dentry_delete(struct dentry *);
+
+/* support routines */
+static int coda_venus_readdir(struct file *filp, filldir_t filldir,
+			      void *dirent, struct dentry *dir);
+int coda_fsync(struct file *, struct dentry *dentry, int datasync);
+
+/* same as fs/bad_inode.c */
+static int coda_return_EIO(void)
+{
+	return -EIO;
+}
+#define CODA_EIO_ERROR ((void *) (coda_return_EIO))
+
+static struct dentry_operations coda_dentry_operations =
+{
+	.d_revalidate	= coda_dentry_revalidate,
+	.d_delete	= coda_dentry_delete,
+};
+
+struct inode_operations coda_dir_inode_operations =
+{
+	.create		= coda_create,
+	.lookup		= coda_lookup,
+	.link		= coda_link,
+	.unlink		= coda_unlink,
+	.symlink	= coda_symlink,
+	.mkdir		= coda_mkdir,
+	.rmdir		= coda_rmdir,
+	.mknod		= CODA_EIO_ERROR,
+	.rename		= coda_rename,
+	.permission	= coda_permission,
+	.getattr	= coda_getattr,
+	.setattr	= coda_setattr,
+};
+
+struct file_operations coda_dir_operations = {
+	.llseek		= generic_file_llseek,
+	.read		= generic_read_dir,
+	.readdir	= coda_readdir,
+	.open		= coda_open,
+	.flush		= coda_flush,
+	.release	= coda_release,
+	.fsync		= coda_fsync,
+};
+
+
+/* inode operations for directories */
+/* access routines: lookup, readlink, permission */
+static struct dentry *coda_lookup(struct inode *dir, struct dentry *entry, struct nameidata *nd)
+{
+	struct inode *res_inode = NULL;
+	struct CodaFid resfid = { { 0, } };
+	int dropme = 0; /* to indicate entry should not be cached */
+	int type = 0;
+	int error = 0;
+	const char *name = entry->d_name.name;
+	size_t length = entry->d_name.len;
+	
+	if ( length > CODA_MAXNAMLEN ) {
+	        printk("name too long: lookup, %s (%*s)\n", 
+		       coda_i2s(dir), (int)length, name);
+		return ERR_PTR(-ENAMETOOLONG);
+	}
+
+	lock_kernel();
+        /* control object, create inode on the fly */
+        if (coda_isroot(dir) && coda_iscontrol(name, length)) {
+	        error = coda_cnode_makectl(&res_inode, dir->i_sb);
+		dropme = 1;
+                goto exit;
+        }
+
+	error = venus_lookup(dir->i_sb, coda_i2f(dir), 
+			     (const char *)name, length, &type, &resfid);
+
+	res_inode = NULL;
+	if (!error) {
+		if (type & CODA_NOCACHE) {
+			type &= (~CODA_NOCACHE);
+			dropme = 1;
+		}
+
+	    	error = coda_cnode_make(&res_inode, &resfid, dir->i_sb);
+		if (error) {
+			unlock_kernel();
+			return ERR_PTR(error);
+		}
+	} else if (error != -ENOENT) {
+		unlock_kernel();
+		return ERR_PTR(error);
+	}
+
+exit:
+	entry->d_time = 0;
+	entry->d_op = &coda_dentry_operations;
+	d_add(entry, res_inode);
+	if ( dropme ) {
+		d_drop(entry);
+		coda_flag_inode(res_inode, C_VATTR);
+	}
+	unlock_kernel();
+        return NULL;
+}
+
+
+int coda_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+        int error = 0;
+ 
+	if (!mask)
+		return 0; 
+
+	lock_kernel();
+
+	coda_vfs_stat.permission++;
+
+	if (coda_cache_check(inode, mask))
+		goto out; 
+
+        error = venus_access(inode->i_sb, coda_i2f(inode), mask);
+    
+	if (!error)
+		coda_cache_enter(inode, mask);
+
+ out:
+	unlock_kernel();
+
+        return error; 
+}
+
+
+static inline void coda_dir_changed(struct inode *dir, int link)
+{
+#ifdef REQUERY_VENUS_FOR_MTIME
+	/* invalidate the directory cnode's attributes so we refetch the
+	 * attributes from venus next time the inode is referenced */
+	coda_flag_inode(dir, C_VATTR);
+#else
+	/* optimistically we can also act as if our nose bleeds. The
+         * granularity of the mtime is coarse anyways so we might actually be
+         * right most of the time. Note: we only do this for directories. */
+	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+#endif
+	if (link)
+		dir->i_nlink += link;
+}
+
+/* creation routines: create, mknod, mkdir, link, symlink */
+static int coda_create(struct inode *dir, struct dentry *de, int mode, struct nameidata *nd)
+{
+        int error=0;
+	const char *name=de->d_name.name;
+	int length=de->d_name.len;
+	struct inode *inode;
+	struct CodaFid newfid;
+	struct coda_vattr attrs;
+
+	lock_kernel();
+	coda_vfs_stat.create++;
+
+	if (coda_isroot(dir) && coda_iscontrol(name, length)) {
+		unlock_kernel();
+		return -EPERM;
+	}
+
+	error = venus_create(dir->i_sb, coda_i2f(dir), name, length, 
+				0, mode, &newfid, &attrs);
+
+        if ( error ) {
+		unlock_kernel();
+		d_drop(de);
+		return error;
+	}
+
+	inode = coda_iget(dir->i_sb, &newfid, &attrs);
+	if ( IS_ERR(inode) ) {
+		unlock_kernel();
+		d_drop(de);
+		return PTR_ERR(inode);
+	}
+
+	/* invalidate the directory cnode's attributes */
+	coda_dir_changed(dir, 0);
+	unlock_kernel();
+	d_instantiate(de, inode);
+        return 0;
+}
+
+static int coda_mkdir(struct inode *dir, struct dentry *de, int mode)
+{
+	struct inode *inode;
+	struct coda_vattr attrs;
+	const char *name = de->d_name.name;
+	int len = de->d_name.len;
+	int error;
+	struct CodaFid newfid;
+
+	lock_kernel();
+	coda_vfs_stat.mkdir++;
+
+	if (coda_isroot(dir) && coda_iscontrol(name, len)) {
+		unlock_kernel();
+		return -EPERM;
+	}
+
+	attrs.va_mode = mode;
+	error = venus_mkdir(dir->i_sb, coda_i2f(dir), 
+			       name, len, &newfid, &attrs);
+        
+        if ( error ) {
+		unlock_kernel();
+		d_drop(de);
+		return error;
+        }
+         
+	inode = coda_iget(dir->i_sb, &newfid, &attrs);
+	if ( IS_ERR(inode) ) {
+		unlock_kernel();
+		d_drop(de);
+		return PTR_ERR(inode);
+	}
+	
+	/* invalidate the directory cnode's attributes */
+	coda_dir_changed(dir, 1);
+	unlock_kernel();
+	d_instantiate(de, inode);
+        return 0;
+}
+
+/* try to make de an entry in dir_inodde linked to source_de */ 
+static int coda_link(struct dentry *source_de, struct inode *dir_inode, 
+	  struct dentry *de)
+{
+	struct inode *inode = source_de->d_inode;
+        const char * name = de->d_name.name;
+	int len = de->d_name.len;
+	int error;
+
+	lock_kernel();
+	coda_vfs_stat.link++;
+
+	if (coda_isroot(dir_inode) && coda_iscontrol(name, len)) {
+		unlock_kernel();
+		return -EPERM;
+	}
+
+	error = venus_link(dir_inode->i_sb, coda_i2f(inode),
+			   coda_i2f(dir_inode), (const char *)name, len);
+
+	if (error) { 
+		d_drop(de);
+		goto out;
+	}
+
+	coda_dir_changed(dir_inode, 0);
+	atomic_inc(&inode->i_count);
+	d_instantiate(de, inode);
+	inode->i_nlink++;
+        
+out:
+	unlock_kernel();
+	return(error);
+}
+
+
+static int coda_symlink(struct inode *dir_inode, struct dentry *de,
+			const char *symname)
+{
+        const char *name = de->d_name.name;
+	int len = de->d_name.len;
+	int symlen;
+        int error=0;
+        
+	lock_kernel();
+	coda_vfs_stat.symlink++;
+
+	if (coda_isroot(dir_inode) && coda_iscontrol(name, len)) {
+		unlock_kernel();
+		return -EPERM;
+	}
+
+	symlen = strlen(symname);
+	if ( symlen > CODA_MAXPATHLEN ) {
+		unlock_kernel();
+		return -ENAMETOOLONG;
+	}
+
+	/*
+	 * This entry is now negative. Since we do not create
+	 * an inode for the entry we have to drop it. 
+	 */
+	d_drop(de);
+	error = venus_symlink(dir_inode->i_sb, coda_i2f(dir_inode), name, len, 
+			      symname, symlen);
+
+	/* mtime is no good anymore */
+	if ( !error )
+		coda_dir_changed(dir_inode, 0);
+
+	unlock_kernel();
+        return error;
+}
+
+/* destruction routines: unlink, rmdir */
+int coda_unlink(struct inode *dir, struct dentry *de)
+{
+        int error;
+	const char *name = de->d_name.name;
+	int len = de->d_name.len;
+
+	lock_kernel();
+	coda_vfs_stat.unlink++;
+
+        error = venus_remove(dir->i_sb, coda_i2f(dir), name, len);
+        if ( error ) {
+		unlock_kernel();
+                return error;
+        }
+
+	coda_dir_changed(dir, 0);
+	de->d_inode->i_nlink--;
+	unlock_kernel();
+
+        return 0;
+}
+
+int coda_rmdir(struct inode *dir, struct dentry *de)
+{
+	const char *name = de->d_name.name;
+	int len = de->d_name.len;
+        int error;
+
+	lock_kernel();
+	coda_vfs_stat.rmdir++;
+
+	if (!d_unhashed(de)) {
+		unlock_kernel();
+		return -EBUSY;
+	}
+	error = venus_rmdir(dir->i_sb, coda_i2f(dir), name, len);
+
+        if ( error ) {
+		unlock_kernel();
+                return error;
+        }
+
+	coda_dir_changed(dir, -1);
+	de->d_inode->i_nlink--;
+	d_delete(de);
+	unlock_kernel();
+
+        return 0;
+}
+
+/* rename */
+static int coda_rename(struct inode *old_dir, struct dentry *old_dentry, 
+		       struct inode *new_dir, struct dentry *new_dentry)
+{
+        const char *old_name = old_dentry->d_name.name;
+        const char *new_name = new_dentry->d_name.name;
+	int old_length = old_dentry->d_name.len;
+	int new_length = new_dentry->d_name.len;
+        int link_adjust = 0;
+        int error;
+
+	lock_kernel();
+	coda_vfs_stat.rename++;
+
+        error = venus_rename(old_dir->i_sb, coda_i2f(old_dir), 
+			     coda_i2f(new_dir), old_length, new_length, 
+			     (const char *) old_name, (const char *)new_name);
+
+        if ( !error ) {
+		if ( new_dentry->d_inode ) {
+			if ( S_ISDIR(new_dentry->d_inode->i_mode) )
+                        	link_adjust = 1;
+
+                        coda_dir_changed(old_dir, -link_adjust);
+                        coda_dir_changed(new_dir,  link_adjust);
+			coda_flag_inode(new_dentry->d_inode, C_VATTR);
+		} else {
+			coda_flag_inode(old_dir, C_VATTR);
+			coda_flag_inode(new_dir, C_VATTR);
+                }
+	}
+	unlock_kernel();
+
+	return error;
+}
+
+
+/* file operations for directories */
+int coda_readdir(struct file *coda_file, void *dirent, filldir_t filldir)
+{
+	struct dentry *coda_dentry = coda_file->f_dentry;
+	struct coda_file_info *cfi;
+	struct file *host_file;
+	struct inode *host_inode;
+	int ret;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	coda_vfs_stat.readdir++;
+
+	host_inode = host_file->f_dentry->d_inode;
+	down(&host_inode->i_sem);
+	host_file->f_pos = coda_file->f_pos;
+
+	if (!host_file->f_op->readdir) {
+		/* Venus: we must read Venus dirents from the file */
+		ret = coda_venus_readdir(host_file, filldir, dirent, coda_dentry);
+	} else {
+		/* potemkin case: we were handed a directory inode. */
+		/* Yuk, we can't call vfs_readdir because we are already
+		 * holding the inode semaphore. */
+		ret = -ENOTDIR;
+		if (!host_file->f_op || !host_file->f_op->readdir)
+			goto out;
+
+		ret = -ENOENT;
+		if (!IS_DEADDIR(host_inode)) {
+			ret = host_file->f_op->readdir(host_file, filldir, dirent);
+			file_accessed(host_file);
+		}
+	}
+out:
+	coda_file->f_pos = host_file->f_pos;
+	up(&host_inode->i_sem);
+
+	return ret;
+}
+
+static inline unsigned int CDT2DT(unsigned char cdt)
+{
+	unsigned int dt;
+
+	switch(cdt) {
+	case CDT_UNKNOWN: dt = DT_UNKNOWN; break;
+	case CDT_FIFO:	  dt = DT_FIFO;    break;
+	case CDT_CHR:	  dt = DT_CHR;     break;
+	case CDT_DIR:	  dt = DT_DIR;     break;
+	case CDT_BLK:	  dt = DT_BLK;     break;
+	case CDT_REG:	  dt = DT_REG;     break;
+	case CDT_LNK:	  dt = DT_LNK;     break;
+	case CDT_SOCK:	  dt = DT_SOCK;    break;
+	case CDT_WHT:	  dt = DT_WHT;     break;
+	default:	  dt = DT_UNKNOWN; break;
+	}
+	return dt;
+}
+
+/* support routines */
+static int coda_venus_readdir(struct file *filp, filldir_t filldir,
+			      void *dirent, struct dentry *dir)
+{
+	int result = 0; /* # of entries returned */
+	struct venus_dirent *vdir;
+	unsigned long vdir_size =
+	    (unsigned long)(&((struct venus_dirent *)0)->d_name);
+	unsigned int type;
+	struct qstr name;
+	ino_t ino;
+	int ret, i;
+
+	vdir = (struct venus_dirent *)kmalloc(sizeof(*vdir), GFP_KERNEL);
+	if (!vdir) return -ENOMEM;
+
+	i = filp->f_pos;
+	switch(i) {
+	case 0:
+		ret = filldir(dirent, ".", 1, 0, dir->d_inode->i_ino, DT_DIR);
+		if (ret < 0) break;
+		result++;
+		filp->f_pos++;
+		/* fallthrough */
+	case 1:
+		ret = filldir(dirent, "..", 2, 1, dir->d_parent->d_inode->i_ino, DT_DIR);
+		if (ret < 0) break;
+		result++;
+		filp->f_pos++;
+		/* fallthrough */
+	default:
+	while (1) {
+		/* read entries from the directory file */
+		ret = kernel_read(filp, filp->f_pos - 2, (char *)vdir,
+				  sizeof(*vdir));
+		if (ret < 0) {
+			printk("coda_venus_readdir: read dir failed %d\n", ret);
+			break;
+		}
+		if (ret == 0) break; /* end of directory file reached */
+
+		/* catch truncated reads */
+		if (ret < vdir_size || ret < vdir_size + vdir->d_namlen) {
+			printk("coda_venus_readdir: short read: %ld\n",
+			       filp->f_dentry->d_inode->i_ino);
+			ret = -EBADF;
+			break;
+		}
+		/* validate whether the directory file actually makes sense */
+		if (vdir->d_reclen < vdir_size + vdir->d_namlen) {
+			printk("coda_venus_readdir: Invalid dir: %ld\n",
+			       filp->f_dentry->d_inode->i_ino);
+			ret = -EBADF;
+			break;
+		}
+
+		name.len = vdir->d_namlen;
+		name.name = vdir->d_name;
+
+		/* Make sure we skip '.' and '..', we already got those */
+		if (name.name[0] == '.' && (name.len == 1 ||
+		    (vdir->d_name[1] == '.' && name.len == 2)))
+			vdir->d_fileno = name.len = 0;
+
+		/* skip null entries */
+		if (vdir->d_fileno && name.len) {
+			/* try to look up this entry in the dcache, that way
+			 * userspace doesn't have to worry about breaking
+			 * getcwd by having mismatched inode numbers for
+			 * internal volume mountpoints. */
+			ino = find_inode_number(dir, &name);
+			if (!ino) ino = vdir->d_fileno;
+
+			type = CDT2DT(vdir->d_type);
+			ret = filldir(dirent, name.name, name.len, filp->f_pos,
+				      ino, type); 
+			/* failure means no space for filling in this round */
+			if (ret < 0) break;
+			result++;
+		}
+		/* we'll always have progress because d_reclen is unsigned and
+		 * we've already established it is non-zero. */
+		filp->f_pos += vdir->d_reclen;
+	}
+	} 
+	kfree(vdir);
+	return result ? result : ret;
+}
+
+/* called when a cache lookup succeeds */
+static int coda_dentry_revalidate(struct dentry *de, struct nameidata *nd)
+{
+	struct inode *inode = de->d_inode;
+	struct coda_inode_info *cii;
+
+	if (!inode)
+		return 1;
+	lock_kernel();
+	if (coda_isroot(inode))
+		goto out;
+	if (is_bad_inode(inode))
+		goto bad;
+
+	cii = ITOC(de->d_inode);
+	if (!(cii->c_flags & (C_PURGE | C_FLUSH)))
+		goto out;
+
+	shrink_dcache_parent(de);
+
+	/* propagate for a flush */
+	if (cii->c_flags & C_FLUSH) 
+		coda_flag_inode_children(inode, C_FLUSH);
+
+	if (atomic_read(&de->d_count) > 1)
+		/* pretend it's valid, but don't change the flags */
+		goto out;
+
+	/* clear the flags. */
+	cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH);
+
+bad:
+	unlock_kernel();
+	return 0;
+out:
+	unlock_kernel();
+	return 1;
+}
+
+/*
+ * This is the callback from dput() when d_count is going to 0.
+ * We use this to unhash dentries with bad inodes.
+ */
+static int coda_dentry_delete(struct dentry * dentry)
+{
+	int flags;
+
+	if (!dentry->d_inode) 
+		return 0;
+
+	flags = (ITOC(dentry->d_inode)->c_flags) & C_PURGE;
+	if (is_bad_inode(dentry->d_inode) || flags) {
+		return 1;
+	}
+	return 0;
+}
+
+
+
+/*
+ * This is called when we want to check if the inode has
+ * changed on the server.  Coda makes this easy since the
+ * cache manager Venus issues a downcall to the kernel when this 
+ * happens 
+ */
+int coda_revalidate_inode(struct dentry *dentry)
+{
+	struct coda_vattr attr;
+	int error = 0;
+	int old_mode;
+	ino_t old_ino;
+	struct inode *inode = dentry->d_inode;
+	struct coda_inode_info *cii = ITOC(inode);
+
+	lock_kernel();
+	if ( !cii->c_flags )
+		goto ok;
+
+	if (cii->c_flags & (C_VATTR | C_PURGE | C_FLUSH)) {
+		error = venus_getattr(inode->i_sb, &(cii->c_fid), &attr);
+		if ( error )
+			goto return_bad;
+
+		/* this inode may be lost if:
+		   - it's ino changed 
+		   - type changes must be permitted for repair and
+		   missing mount points.
+		*/
+		old_mode = inode->i_mode;
+		old_ino = inode->i_ino;
+		coda_vattr_to_iattr(inode, &attr);
+
+		if ((old_mode & S_IFMT) != (inode->i_mode & S_IFMT)) {
+			printk("Coda: inode %ld, fid %s changed type!\n",
+			       inode->i_ino, coda_f2s(&(cii->c_fid)));
+		}
+
+		/* the following can happen when a local fid is replaced 
+		   with a global one, here we lose and declare the inode bad */
+		if (inode->i_ino != old_ino)
+			goto return_bad;
+		
+		coda_flag_inode_children(inode, C_FLUSH);
+		cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH);
+	}
+
+ok:
+	unlock_kernel();
+	return 0;
+
+return_bad:
+	unlock_kernel();
+	return -EIO;
+}