X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Fopen.c;h=f53a5b9ffb7dce308f6e0e05d4982d343261564c;hb=f3f6ec4b77f627a6427460d6f8884e1042eef134;hp=f0d90cf0495c490316d427e309c38695ceb4e005;hpb=deb75f3c29a13ac37a50d82a256c8dc17de58c3d;p=linux-2.6 diff --git a/fs/open.c b/fs/open.c index f0d90cf049..f53a5b9ffb 100644 --- a/fs/open.c +++ b/fs/open.c @@ -194,7 +194,7 @@ out: return error; } -int do_truncate(struct dentry *dentry, loff_t length) +int do_truncate(struct dentry *dentry, loff_t length, struct file *filp) { int err; struct iattr newattrs; @@ -205,6 +205,10 @@ int do_truncate(struct dentry *dentry, loff_t length) newattrs.ia_size = length; newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME; + if (filp) { + newattrs.ia_file = filp; + newattrs.ia_valid |= ATTR_FILE; + } down(&dentry->d_inode->i_sem); err = notify_change(dentry, &newattrs); @@ -236,7 +240,7 @@ static inline long do_sys_truncate(const char __user * path, loff_t length) if (!S_ISREG(inode->i_mode)) goto dput_and_out; - error = permission(inode,MAY_WRITE,&nd); + error = vfs_permission(&nd, MAY_WRITE); if (error) goto dput_and_out; @@ -262,7 +266,7 @@ static inline long do_sys_truncate(const char __user * path, loff_t length) error = locks_verify_truncate(inode, NULL, length); if (!error) { DQUOT_INIT(inode); - error = do_truncate(nd.dentry, length); + error = do_truncate(nd.dentry, length, NULL); } put_write_access(inode); @@ -314,7 +318,7 @@ static inline long do_sys_ftruncate(unsigned int fd, loff_t length, int small) error = locks_verify_truncate(inode, file, length); if (!error) - error = do_truncate(dentry, length); + error = do_truncate(dentry, length, file); out_putf: fput(file); out: @@ -390,7 +394,7 @@ asmlinkage long sys_utime(char __user * filename, struct utimbuf __user * times) goto dput_and_out; if (current->fsuid != inode->i_uid && - (error = permission(inode,MAY_WRITE,&nd)) != 0) + (error = vfs_permission(&nd, MAY_WRITE)) != 0) goto dput_and_out; } down(&inode->i_sem); @@ -443,7 +447,7 @@ long do_utimes(char __user * filename, struct timeval * times) goto dput_and_out; if (current->fsuid != inode->i_uid && - (error = permission(inode,MAY_WRITE,&nd)) != 0) + (error = vfs_permission(&nd, MAY_WRITE)) != 0) goto dput_and_out; } down(&inode->i_sem); @@ -502,7 +506,7 @@ asmlinkage long sys_access(const char __user * filename, int mode) res = __user_walk(filename, LOOKUP_FOLLOW|LOOKUP_ACCESS, &nd); if (!res) { - res = permission(nd.dentry->d_inode, mode, &nd); + res = vfs_permission(&nd, mode); /* SuS v2 requires we report a read only fs too */ if(!res && (mode & S_IWOTH) && IS_RDONLY(nd.dentry->d_inode) && !special_file(nd.dentry->d_inode->i_mode)) @@ -526,7 +530,7 @@ asmlinkage long sys_chdir(const char __user * filename) if (error) goto out; - error = permission(nd.dentry->d_inode,MAY_EXEC,&nd); + error = vfs_permission(&nd, MAY_EXEC); if (error) goto dput_and_out; @@ -559,7 +563,7 @@ asmlinkage long sys_fchdir(unsigned int fd) if (!S_ISDIR(inode->i_mode)) goto out_putf; - error = permission(inode, MAY_EXEC, NULL); + error = file_permission(file, MAY_EXEC); if (!error) set_fs_pwd(current->fs, mnt, dentry); out_putf: @@ -577,7 +581,7 @@ asmlinkage long sys_chroot(const char __user * filename) if (error) goto out; - error = permission(nd.dentry->d_inode,MAY_EXEC,&nd); + error = vfs_permission(&nd, MAY_EXEC); if (error) goto dput_and_out; @@ -739,7 +743,8 @@ asmlinkage long sys_fchown(unsigned int fd, uid_t user, gid_t group) } static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, - int flags, struct file *f) + int flags, struct file *f, + int (*open)(struct inode *, struct file *)) { struct inode *inode; int error; @@ -761,11 +766,14 @@ static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, f->f_op = fops_get(inode->i_fop); file_move(f, &inode->i_sb->s_files); - if (f->f_op && f->f_op->open) { - error = f->f_op->open(inode,f); + if (!open && f->f_op) + open = f->f_op->open; + if (open) { + error = open(inode, f); if (error) goto cleanup_all; } + f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); @@ -814,28 +822,79 @@ struct file *filp_open(const char * filename, int flags, int mode) { int namei_flags, error; struct nameidata nd; - struct file *f; namei_flags = flags; if ((namei_flags+1) & O_ACCMODE) namei_flags++; - if (namei_flags & O_TRUNC) - namei_flags |= 2; - - error = -ENFILE; - f = get_empty_filp(); - if (f == NULL) - return ERR_PTR(error); error = open_namei(filename, namei_flags, mode, &nd); if (!error) - return __dentry_open(nd.dentry, nd.mnt, flags, f); + return nameidata_to_filp(&nd, flags); - put_filp(f); return ERR_PTR(error); } EXPORT_SYMBOL(filp_open); +/** + * lookup_instantiate_filp - instantiates the open intent filp + * @nd: pointer to nameidata + * @dentry: pointer to dentry + * @open: open callback + * + * Helper for filesystems that want to use lookup open intents and pass back + * a fully instantiated struct file to the caller. + * This function is meant to be called from within a filesystem's + * lookup method. + * Note that in case of error, nd->intent.open.file is destroyed, but the + * path information remains valid. + * If the open callback is set to NULL, then the standard f_op->open() + * filesystem callback is substituted. + */ +struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry, + int (*open)(struct inode *, struct file *)) +{ + if (IS_ERR(nd->intent.open.file)) + goto out; + if (IS_ERR(dentry)) + goto out_err; + nd->intent.open.file = __dentry_open(dget(dentry), mntget(nd->mnt), + nd->intent.open.flags - 1, + nd->intent.open.file, + open); +out: + return nd->intent.open.file; +out_err: + release_open_intent(nd); + nd->intent.open.file = (struct file *)dentry; + goto out; +} +EXPORT_SYMBOL_GPL(lookup_instantiate_filp); + +/** + * nameidata_to_filp - convert a nameidata to an open filp. + * @nd: pointer to nameidata + * @flags: open flags + * + * Note that this function destroys the original nameidata + */ +struct file *nameidata_to_filp(struct nameidata *nd, int flags) +{ + struct file *filp; + + /* Pick up the filp from the open intent */ + filp = nd->intent.open.file; + /* Has the filesystem initialised the file for us? */ + if (filp->f_dentry == NULL) + filp = __dentry_open(nd->dentry, nd->mnt, flags, filp, NULL); + else + path_release(nd); + return filp; +} + +/* + * dentry_open() will have done dput(dentry) and mntput(mnt) if it returns an + * error. + */ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) { int error; @@ -843,10 +902,13 @@ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags) error = -ENFILE; f = get_empty_filp(); - if (f == NULL) + if (f == NULL) { + dput(dentry); + mntput(mnt); return ERR_PTR(error); + } - return __dentry_open(dentry, mnt, flags, f); + return __dentry_open(dentry, mnt, flags, f, NULL); } EXPORT_SYMBOL(dentry_open);