diff options
Diffstat (limited to 'fs/ocfs2/dlm/dlmfs.c')
| -rw-r--r-- | fs/ocfs2/dlm/dlmfs.c | 710 |
1 files changed, 0 insertions, 710 deletions
diff --git a/fs/ocfs2/dlm/dlmfs.c b/fs/ocfs2/dlm/dlmfs.c deleted file mode 100644 index ddf55da..0000000 --- a/fs/ocfs2/dlm/dlmfs.c +++ /dev/null @@ -1,710 +0,0 @@ -/* -*- mode: c; c-basic-offset: 8; -*- - * vim: noexpandtab sw=8 ts=8 sts=0: - * - * dlmfs.c - * - * Code which implements the kernel side of a minimal userspace - * interface to our DLM. This file handles the virtual file system - * used for communication with userspace. Credit should go to ramfs, - * which was a template for the fs side of this module. - * - * Copyright (C) 2003, 2004 Oracle. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 021110-1307, USA. - */ - -/* Simple VFS hooks based on: */ -/* - * Resizable simple ram filesystem for Linux. - * - * Copyright (C) 2000 Linus Torvalds. - * 2000 Transmeta Corp. - */ - -#include <linux/module.h> -#include <linux/fs.h> -#include <linux/pagemap.h> -#include <linux/types.h> -#include <linux/slab.h> -#include <linux/highmem.h> -#include <linux/init.h> -#include <linux/string.h> -#include <linux/backing-dev.h> -#include <linux/poll.h> - -#include <asm/uaccess.h> - - -#include "cluster/nodemanager.h" -#include "cluster/heartbeat.h" -#include "cluster/tcp.h" - -#include "dlmapi.h" - -#include "userdlm.h" - -#include "dlmfsver.h" - -#define MLOG_MASK_PREFIX ML_DLMFS -#include "cluster/masklog.h" - -#include "ocfs2_lockingver.h" - -static const struct super_operations dlmfs_ops; -static const struct file_operations dlmfs_file_operations; -static const struct inode_operations dlmfs_dir_inode_operations; -static const struct inode_operations dlmfs_root_inode_operations; -static const struct inode_operations dlmfs_file_inode_operations; -static struct kmem_cache *dlmfs_inode_cache; - -struct workqueue_struct *user_dlm_worker; - -/* - * This is the userdlmfs locking protocol version. - * - * See fs/ocfs2/dlmglue.c for more details on locking versions. - */ -static const struct dlm_protocol_version user_locking_protocol = { - .pv_major = OCFS2_LOCKING_PROTOCOL_MAJOR, - .pv_minor = OCFS2_LOCKING_PROTOCOL_MINOR, -}; - - -/* - * These are the ABI capabilities of dlmfs. - * - * Over time, dlmfs has added some features that were not part of the - * initial ABI. Unfortunately, some of these features are not detectable - * via standard usage. For example, Linux's default poll always returns - * POLLIN, so there is no way for a caller of poll(2) to know when dlmfs - * added poll support. Instead, we provide this list of new capabilities. - * - * Capabilities is a read-only attribute. We do it as a module parameter - * so we can discover it whether dlmfs is built in, loaded, or even not - * loaded. - * - * The ABI features are local to this machine's dlmfs mount. This is - * distinct from the locking protocol, which is concerned with inter-node - * interaction. - * - * Capabilities: - * - bast : POLLIN against the file descriptor of a held lock - * signifies a bast fired on the lock. - */ -#define DLMFS_CAPABILITIES "bast" -extern int param_set_dlmfs_capabilities(const char *val, - struct kernel_param *kp) -{ - printk(KERN_ERR "%s: readonly parameter\n", kp->name); - return -EINVAL; -} -static int param_get_dlmfs_capabilities(char *buffer, - struct kernel_param *kp) -{ - return strlcpy(buffer, DLMFS_CAPABILITIES, - strlen(DLMFS_CAPABILITIES) + 1); -} -module_param_call(capabilities, param_set_dlmfs_capabilities, - param_get_dlmfs_capabilities, NULL, 0444); -MODULE_PARM_DESC(capabilities, DLMFS_CAPABILITIES); - - -/* - * decodes a set of open flags into a valid lock level and a set of flags. - * returns < 0 if we have invalid flags - * flags which mean something to us: - * O_RDONLY -> PRMODE level - * O_WRONLY -> EXMODE level - * - * O_NONBLOCK -> LKM_NOQUEUE - */ -static int dlmfs_decode_open_flags(int open_flags, - int *level, - int *flags) -{ - if (open_flags & (O_WRONLY|O_RDWR)) - *level = LKM_EXMODE; - else - *level = LKM_PRMODE; - - *flags = 0; - if (open_flags & O_NONBLOCK) - *flags |= LKM_NOQUEUE; - - return 0; -} - -static int dlmfs_file_open(struct inode *inode, - struct file *file) -{ - int status, level, flags; - struct dlmfs_filp_private *fp = NULL; - struct dlmfs_inode_private *ip; - - if (S_ISDIR(inode->i_mode)) - BUG(); - - mlog(0, "open called on inode %lu, flags 0x%x\n", inode->i_ino, - file->f_flags); - - status = dlmfs_decode_open_flags(file->f_flags, &level, &flags); - if (status < 0) - goto bail; - - /* We don't want to honor O_APPEND at read/write time as it - * doesn't make sense for LVB writes. */ - file->f_flags &= ~O_APPEND; - - fp = kmalloc(sizeof(*fp), GFP_NOFS); - if (!fp) { - status = -ENOMEM; - goto bail; - } - fp->fp_lock_level = level; - - ip = DLMFS_I(inode); - - status = user_dlm_cluster_lock(&ip->ip_lockres, level, flags); - if (status < 0) { - /* this is a strange error to return here but I want - * to be able userspace to be able to distinguish a - * valid lock request from one that simply couldn't be - * granted. */ - if (flags & LKM_NOQUEUE && status == -EAGAIN) - status = -ETXTBSY; - kfree(fp); - goto bail; - } - - file->private_data = fp; -bail: - return status; -} - -static int dlmfs_file_release(struct inode *inode, - struct file *file) -{ - int level, status; - struct dlmfs_inode_private *ip = DLMFS_I(inode); - struct dlmfs_filp_private *fp = - (struct dlmfs_filp_private *) file->private_data; - - if (S_ISDIR(inode->i_mode)) - BUG(); - - mlog(0, "close called on inode %lu\n", inode->i_ino); - - status = 0; - if (fp) { - level = fp->fp_lock_level; - if (level != LKM_IVMODE) - user_dlm_cluster_unlock(&ip->ip_lockres, level); - - kfree(fp); - file->private_data = NULL; - } - - return 0; -} - -static unsigned int dlmfs_file_poll(struct file *file, poll_table *wait) -{ - int event = 0; - struct inode *inode = file->f_path.dentry->d_inode; - struct dlmfs_inode_private *ip = DLMFS_I(inode); - - poll_wait(file, &ip->ip_lockres.l_event, wait); - - spin_lock(&ip->ip_lockres.l_lock); - if (ip->ip_lockres.l_flags & USER_LOCK_BLOCKED) - event = POLLIN | POLLRDNORM; - spin_unlock(&ip->ip_lockres.l_lock); - - return event; -} - -static ssize_t dlmfs_file_read(struct file *filp, - char __user *buf, - size_t count, - loff_t *ppos) -{ - int bytes_left; - ssize_t readlen; - char *lvb_buf; - struct inode *inode = filp->f_path.dentry->d_inode; - - mlog(0, "inode %lu, count = %zu, *ppos = %llu\n", - inode->i_ino, count, *ppos); - - if (*ppos >= i_size_read(inode)) - return 0; - - if (!count) - return 0; - - if (!access_ok(VERIFY_WRITE, buf, count)) - return -EFAULT; - - /* don't read past the lvb */ - if ((count + *ppos) > i_size_read(inode)) - readlen = i_size_read(inode) - *ppos; - else - readlen = count - *ppos; - - lvb_buf = kmalloc(readlen, GFP_NOFS); - if (!lvb_buf) - return -ENOMEM; - - user_dlm_read_lvb(inode, lvb_buf, readlen); - bytes_left = __copy_to_user(buf, lvb_buf, readlen); - readlen -= bytes_left; - - kfree(lvb_buf); - - *ppos = *ppos + readlen; - - mlog(0, "read %zd bytes\n", readlen); - return readlen; -} - -static ssize_t dlmfs_file_write(struct file *filp, - const char __user *buf, - size_t count, - loff_t *ppos) -{ - int bytes_left; - ssize_t writelen; - char *lvb_buf; - struct inode *inode = filp->f_path.dentry->d_inode; - - mlog(0, "inode %lu, count = %zu, *ppos = %llu\n", - inode->i_ino, count, *ppos); - - if (*ppos >= i_size_read(inode)) - return -ENOSPC; - - if (!count) - return 0; - - if (!access_ok(VERIFY_READ, buf, count)) - return -EFAULT; - - /* don't write past the lvb */ - if ((count + *ppos) > i_size_read(inode)) - writelen = i_size_read(inode) - *ppos; - else - writelen = count - *ppos; - - lvb_buf = kmalloc(writelen, GFP_NOFS); - if (!lvb_buf) - return -ENOMEM; - - bytes_left = copy_from_user(lvb_buf, buf, writelen); - writelen -= bytes_left; - if (writelen) - user_dlm_write_lvb(inode, lvb_buf, writelen); - - kfree(lvb_buf); - - *ppos = *ppos + writelen; - mlog(0, "wrote %zd bytes\n", writelen); - return writelen; -} - -static void dlmfs_init_once(void *foo) -{ - struct dlmfs_inode_private *ip = - (struct dlmfs_inode_private *) foo; - - ip->ip_dlm = NULL; - ip->ip_parent = NULL; - - inode_init_once(&ip->ip_vfs_inode); -} - -static struct inode *dlmfs_alloc_inode(struct super_block *sb) -{ - struct dlmfs_inode_private *ip; - - ip = kmem_cache_alloc(dlmfs_inode_cache, GFP_NOFS); - if (!ip) - return NULL; - - return &ip->ip_vfs_inode; -} - -static void dlmfs_destroy_inode(struct inode *inode) -{ - kmem_cache_free(dlmfs_inode_cache, DLMFS_I(inode)); -} - -static void dlmfs_clear_inode(struct inode *inode) -{ - int status; - struct dlmfs_inode_private *ip; - - if (!inode) - return; - - mlog(0, "inode %lu\n", inode->i_ino); - - ip = DLMFS_I(inode); - - if (S_ISREG(inode->i_mode)) { - status = user_dlm_destroy_lock(&ip->ip_lockres); - if (status < 0) - mlog_errno(status); - iput(ip->ip_parent); - goto clear_fields; - } - - mlog(0, "we're a directory, ip->ip_dlm = 0x%p\n", ip->ip_dlm); - /* we must be a directory. If required, lets unregister the - * dlm context now. */ - if (ip->ip_dlm) - user_dlm_unregister_context(ip->ip_dlm); -clear_fields: - ip->ip_parent = NULL; - ip->ip_dlm = NULL; -} - -static struct backing_dev_info dlmfs_backing_dev_info = { - .name = "ocfs2-dlmfs", - .ra_pages = 0, /* No readahead */ - .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, -}; - -static struct inode *dlmfs_get_root_inode(struct super_block *sb) -{ - struct inode *inode = new_inode(sb); - int mode = S_IFDIR | 0755; - struct dlmfs_inode_private *ip; - - if (inode) { - ip = DLMFS_I(inode); - - inode->i_mode = mode; - inode->i_uid = current_fsuid(); - inode->i_gid = current_fsgid(); - inode->i_mapping->backing_dev_info = &dlmfs_backing_dev_info; - inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; - inc_nlink(inode); - - inode->i_fop = &simple_dir_operations; - inode->i_op = &dlmfs_root_inode_operations; - } - - return inode; -} - -static struct inode *dlmfs_get_inode(struct inode *parent, - struct dentry *dentry, - int mode) -{ - struct super_block *sb = parent->i_sb; - struct inode * inode = new_inode(sb); - struct dlmfs_inode_private *ip; - - if (!inode) - return NULL; - - inode->i_mode = mode; - inode->i_uid = current_fsuid(); - inode->i_gid = current_fsgid(); - inode->i_mapping->backing_dev_info = &dlmfs_backing_dev_info; - inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; - - ip = DLMFS_I(inode); - ip->ip_dlm = DLMFS_I(parent)->ip_dlm; - - switch (mode & S_IFMT) { - default: - /* for now we don't support anything other than - * directories and regular files. */ - BUG(); - break; - case S_IFREG: - inode->i_op = &dlmfs_file_inode_operations; - inode->i_fop = &dlmfs_file_operations; - - i_size_write(inode, DLM_LVB_LEN); - - user_dlm_lock_res_init(&ip->ip_lockres, dentry); - - /* released at clear_inode time, this insures that we - * get to drop the dlm reference on each lock *before* - * we call the unregister code for releasing parent - * directories. */ - ip->ip_parent = igrab(parent); - BUG_ON(!ip->ip_parent); - break; - case S_IFDIR: - inode->i_op = &dlmfs_dir_inode_operations; - inode->i_fop = &simple_dir_operations; - - /* directory inodes start off with i_nlink == - * 2 (for "." entry) */ - inc_nlink(inode); - break; - } - - if (parent->i_mode & S_ISGID) { - inode->i_gid = parent->i_gid; - if (S_ISDIR(mode)) - inode->i_mode |= S_ISGID; - } - - return inode; -} - -/* - * File creation. Allocate an inode, and we're done.. - */ -/* SMP-safe */ -static int dlmfs_mkdir(struct inode * dir, - struct dentry * dentry, - int mode) -{ - int status; - struct inode *inode = NULL; - struct qstr *domain = &dentry->d_name; - struct dlmfs_inode_private *ip; - struct dlm_ctxt *dlm; - struct dlm_protocol_version proto = user_locking_protocol; - - mlog(0, "mkdir %.*s\n", domain->len, domain->name); - - /* verify that we have a proper domain */ - if (domain->len >= O2NM_MAX_NAME_LEN) { - status = -EINVAL; - mlog(ML_ERROR, "invalid domain name for directory.\n"); - goto bail; - } - - inode = dlmfs_get_inode(dir, dentry, mode | S_IFDIR); - if (!inode) { - status = -ENOMEM; - mlog_errno(status); - goto bail; - } - - ip = DLMFS_I(inode); - - dlm = user_dlm_register_context(domain, &proto); - if (IS_ERR(dlm)) { - status = PTR_ERR(dlm); - mlog(ML_ERROR, "Error %d could not register domain \"%.*s\"\n", - status, domain->len, domain->name); - goto bail; - } - ip->ip_dlm = dlm; - - inc_nlink(dir); - d_instantiate(dentry, inode); - dget(dentry); /* Extra count - pin the dentry in core */ - - status = 0; -bail: - if (status < 0) - iput(inode); - return status; -} - -static int dlmfs_create(struct inode *dir, - struct dentry *dentry, - int mode, - struct nameidata *nd) -{ - int status = 0; - struct inode *inode; - struct qstr *name = &dentry->d_name; - - mlog(0, "create %.*s\n", name->len, name->name); - - /* verify name is valid and doesn't contain any dlm reserved - * characters */ - if (name->len >= USER_DLM_LOCK_ID_MAX_LEN || - name->name[0] == '$') { - status = -EINVAL; - mlog(ML_ERROR, "invalid lock name, %.*s\n", name->len, - name->name); - goto bail; - } - - inode = dlmfs_get_inode(dir, dentry, mode | S_IFREG); - if (!inode) { - status = -ENOMEM; - mlog_errno(status); - goto bail; - } - - d_instantiate(dentry, inode); - dget(dentry); /* Extra count - pin the dentry in core */ -bail: - return status; -} - -static int dlmfs_unlink(struct inode *dir, - struct dentry *dentry) -{ - int status; - struct inode *inode = dentry->d_inode; - - mlog(0, "unlink inode %lu\n", inode->i_ino); - - /* if there are no current holders, or none that are waiting - * to acquire a lock, this basically destroys our lockres. */ - status = user_dlm_destroy_lock(&DLMFS_I(inode)->ip_lockres); - if (status < 0) { - mlog(ML_ERROR, "unlink %.*s, error %d from destroy\n", - dentry->d_name.len, dentry->d_name.name, status); - goto bail; - } - status = simple_unlink(dir, dentry); -bail: - return status; -} - -static int dlmfs_fill_super(struct super_block * sb, - void * data, - int silent) -{ - struct inode * inode; - struct dentry * root; - - sb->s_maxbytes = MAX_LFS_FILESIZE; - sb->s_blocksize = PAGE_CACHE_SIZE; - sb->s_blocksize_bits = PAGE_CACHE_SHIFT; - sb->s_magic = DLMFS_MAGIC; - sb->s_op = &dlmfs_ops; - inode = dlmfs_get_root_inode(sb); - if (!inode) - return -ENOMEM; - - root = d_alloc_root(inode); - if (!root) { - iput(inode); - return -ENOMEM; - } - sb->s_root = root; - return 0; -} - -static const struct file_operations dlmfs_file_operations = { - .open = dlmfs_file_open, - .release = dlmfs_file_release, - .poll = dlmfs_file_poll, - .read = dlmfs_file_read, - .write = dlmfs_file_write, -}; - -static const struct inode_operations dlmfs_dir_inode_operations = { - .create = dlmfs_create, - .lookup = simple_lookup, - .unlink = dlmfs_unlink, -}; - -/* this way we can restrict mkdir to only the toplevel of the fs. */ -static const struct inode_operations dlmfs_root_inode_operations = { - .lookup = simple_lookup, - .mkdir = dlmfs_mkdir, - .rmdir = simple_rmdir, -}; - -static const struct super_operations dlmfs_ops = { - .statfs = simple_statfs, - .alloc_inode = dlmfs_alloc_inode, - .destroy_inode = dlmfs_destroy_inode, - .clear_inode = dlmfs_clear_inode, - .drop_inode = generic_delete_inode, -}; - -static const struct inode_operations dlmfs_file_inode_operations = { - .getattr = simple_getattr, -}; - -static int dlmfs_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data, struct vfsmount *mnt) -{ - return get_sb_nodev(fs_type, flags, data, dlmfs_fill_super, mnt); -} - -static struct file_system_type dlmfs_fs_type = { - .owner = THIS_MODULE, - .name = "ocfs2_dlmfs", - .get_sb = dlmfs_get_sb, - .kill_sb = kill_litter_super, -}; - -static int __init init_dlmfs_fs(void) -{ - int status; - int cleanup_inode = 0, cleanup_worker = 0; - - dlmfs_print_version(); - - status = bdi_init(&dlmfs_backing_dev_info); - if (status) - return status; - - dlmfs_inode_cache = kmem_cache_create("dlmfs_inode_cache", - sizeof(struct dlmfs_inode_private), - 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| - SLAB_MEM_SPREAD), - dlmfs_init_once); - if (!dlmfs_inode_cache) { - status = -ENOMEM; - goto bail; - } - cleanup_inode = 1; - - user_dlm_worker = create_singlethread_workqueue("user_dlm"); - if (!user_dlm_worker) { - status = -ENOMEM; - goto bail; - } - cleanup_worker = 1; - - status = register_filesystem(&dlmfs_fs_type); -bail: - if (status) { - if (cleanup_inode) - kmem_cache_destroy(dlmfs_inode_cache); - if (cleanup_worker) - destroy_workqueue(user_dlm_worker); - bdi_destroy(&dlmfs_backing_dev_info); - } else - printk("OCFS2 User DLM kernel interface loaded\n"); - return status; -} - -static void __exit exit_dlmfs_fs(void) -{ - unregister_filesystem(&dlmfs_fs_type); - - flush_workqueue(user_dlm_worker); - destroy_workqueue(user_dlm_worker); - - kmem_cache_destroy(dlmfs_inode_cache); - - bdi_destroy(&dlmfs_backing_dev_info); -} - -MODULE_AUTHOR("Oracle"); -MODULE_LICENSE("GPL"); - -module_init(init_dlmfs_fs) -module_exit(exit_dlmfs_fs) |