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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/coda/dir.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/coda/dir.c')
-rw-r--r--fs/coda/dir.c704
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;
+}