From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- fs/ocfs2/stack_user.c | 1102 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1102 insertions(+) create mode 100644 fs/ocfs2/stack_user.c (limited to 'fs/ocfs2/stack_user.c') diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c new file mode 100644 index 000000000..91e19d338 --- /dev/null +++ b/fs/ocfs2/stack_user.c @@ -0,0 +1,1102 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * stack_user.c + * + * Code which interfaces ocfs2 with fs/dlm and a userspace stack. + * + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "stackglue.h" + +#include + +/* + * The control protocol starts with a handshake. Until the handshake + * is complete, the control device will fail all write(2)s. + * + * The handshake is simple. First, the client reads until EOF. Each line + * of output is a supported protocol tag. All protocol tags are a single + * character followed by a two hex digit version number. Currently the + * only things supported is T01, for "Text-base version 0x01". Next, the + * client writes the version they would like to use, including the newline. + * Thus, the protocol tag is 'T01\n'. If the version tag written is + * unknown, -EINVAL is returned. Once the negotiation is complete, the + * client can start sending messages. + * + * The T01 protocol has three messages. First is the "SETN" message. + * It has the following syntax: + * + * SETN<8-char-hex-nodenum> + * + * This is 14 characters. + * + * The "SETN" message must be the first message following the protocol. + * It tells ocfs2_control the local node number. + * + * Next comes the "SETV" message. It has the following syntax: + * + * SETV<2-char-hex-major><2-char-hex-minor> + * + * This is 11 characters. + * + * The "SETV" message sets the filesystem locking protocol version as + * negotiated by the client. The client negotiates based on the maximum + * version advertised in /sys/fs/ocfs2/max_locking_protocol. The major + * number from the "SETV" message must match + * ocfs2_user_plugin.sp_max_proto.pv_major, and the minor number + * must be less than or equal to ...sp_max_version.pv_minor. + * + * Once this information has been set, mounts will be allowed. From this + * point on, the "DOWN" message can be sent for node down notification. + * It has the following syntax: + * + * DOWN<32-char-cap-hex-uuid><8-char-hex-nodenum> + * + * eg: + * + * DOWN 632A924FDD844190BDA93C0DF6B94899 00000001\n + * + * This is 47 characters. + */ + +/* + * Whether or not the client has done the handshake. + * For now, we have just one protocol version. + */ +#define OCFS2_CONTROL_PROTO "T01\n" +#define OCFS2_CONTROL_PROTO_LEN 4 + +/* Handshake states */ +#define OCFS2_CONTROL_HANDSHAKE_INVALID (0) +#define OCFS2_CONTROL_HANDSHAKE_READ (1) +#define OCFS2_CONTROL_HANDSHAKE_PROTOCOL (2) +#define OCFS2_CONTROL_HANDSHAKE_VALID (3) + +/* Messages */ +#define OCFS2_CONTROL_MESSAGE_OP_LEN 4 +#define OCFS2_CONTROL_MESSAGE_SETNODE_OP "SETN" +#define OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN 14 +#define OCFS2_CONTROL_MESSAGE_SETVERSION_OP "SETV" +#define OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN 11 +#define OCFS2_CONTROL_MESSAGE_DOWN_OP "DOWN" +#define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47 +#define OCFS2_TEXT_UUID_LEN 32 +#define OCFS2_CONTROL_MESSAGE_VERNUM_LEN 2 +#define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8 +#define VERSION_LOCK "version_lock" + +enum ocfs2_connection_type { + WITH_CONTROLD, + NO_CONTROLD +}; + +/* + * ocfs2_live_connection is refcounted because the filesystem and + * miscdevice sides can detach in different order. Let's just be safe. + */ +struct ocfs2_live_connection { + struct list_head oc_list; + struct ocfs2_cluster_connection *oc_conn; + enum ocfs2_connection_type oc_type; + atomic_t oc_this_node; + int oc_our_slot; + struct dlm_lksb oc_version_lksb; + char oc_lvb[DLM_LVB_LEN]; + struct completion oc_sync_wait; + wait_queue_head_t oc_wait; +}; + +struct ocfs2_control_private { + struct list_head op_list; + int op_state; + int op_this_node; + struct ocfs2_protocol_version op_proto; +}; + +/* SETN<8-char-hex-nodenum> */ +struct ocfs2_control_message_setn { + char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; + char space; + char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN]; + char newline; +}; + +/* SETV<2-char-hex-major><2-char-hex-minor> */ +struct ocfs2_control_message_setv { + char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; + char space1; + char major[OCFS2_CONTROL_MESSAGE_VERNUM_LEN]; + char space2; + char minor[OCFS2_CONTROL_MESSAGE_VERNUM_LEN]; + char newline; +}; + +/* DOWN<32-char-cap-hex-uuid><8-char-hex-nodenum> */ +struct ocfs2_control_message_down { + char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; + char space1; + char uuid[OCFS2_TEXT_UUID_LEN]; + char space2; + char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN]; + char newline; +}; + +union ocfs2_control_message { + char tag[OCFS2_CONTROL_MESSAGE_OP_LEN]; + struct ocfs2_control_message_setn u_setn; + struct ocfs2_control_message_setv u_setv; + struct ocfs2_control_message_down u_down; +}; + +static struct ocfs2_stack_plugin ocfs2_user_plugin; + +static atomic_t ocfs2_control_opened; +static int ocfs2_control_this_node = -1; +static struct ocfs2_protocol_version running_proto; + +static LIST_HEAD(ocfs2_live_connection_list); +static LIST_HEAD(ocfs2_control_private_list); +static DEFINE_MUTEX(ocfs2_control_lock); + +static inline void ocfs2_control_set_handshake_state(struct file *file, + int state) +{ + struct ocfs2_control_private *p = file->private_data; + p->op_state = state; +} + +static inline int ocfs2_control_get_handshake_state(struct file *file) +{ + struct ocfs2_control_private *p = file->private_data; + return p->op_state; +} + +static struct ocfs2_live_connection *ocfs2_connection_find(const char *name) +{ + size_t len = strlen(name); + struct ocfs2_live_connection *c; + + BUG_ON(!mutex_is_locked(&ocfs2_control_lock)); + + list_for_each_entry(c, &ocfs2_live_connection_list, oc_list) { + if ((c->oc_conn->cc_namelen == len) && + !strncmp(c->oc_conn->cc_name, name, len)) + return c; + } + + return NULL; +} + +/* + * ocfs2_live_connection structures are created underneath the ocfs2 + * mount path. Since the VFS prevents multiple calls to + * fill_super(), we can't get dupes here. + */ +static int ocfs2_live_connection_attach(struct ocfs2_cluster_connection *conn, + struct ocfs2_live_connection *c) +{ + int rc = 0; + + mutex_lock(&ocfs2_control_lock); + c->oc_conn = conn; + + if ((c->oc_type == NO_CONTROLD) || atomic_read(&ocfs2_control_opened)) + list_add(&c->oc_list, &ocfs2_live_connection_list); + else { + printk(KERN_ERR + "ocfs2: Userspace control daemon is not present\n"); + rc = -ESRCH; + } + + mutex_unlock(&ocfs2_control_lock); + return rc; +} + +/* + * This function disconnects the cluster connection from ocfs2_control. + * Afterwards, userspace can't affect the cluster connection. + */ +static void ocfs2_live_connection_drop(struct ocfs2_live_connection *c) +{ + mutex_lock(&ocfs2_control_lock); + list_del_init(&c->oc_list); + c->oc_conn = NULL; + mutex_unlock(&ocfs2_control_lock); + + kfree(c); +} + +static int ocfs2_control_cfu(void *target, size_t target_len, + const char __user *buf, size_t count) +{ + /* The T01 expects write(2) calls to have exactly one command */ + if ((count != target_len) || + (count > sizeof(union ocfs2_control_message))) + return -EINVAL; + + if (copy_from_user(target, buf, target_len)) + return -EFAULT; + + return 0; +} + +static ssize_t ocfs2_control_validate_protocol(struct file *file, + const char __user *buf, + size_t count) +{ + ssize_t ret; + char kbuf[OCFS2_CONTROL_PROTO_LEN]; + + ret = ocfs2_control_cfu(kbuf, OCFS2_CONTROL_PROTO_LEN, + buf, count); + if (ret) + return ret; + + if (strncmp(kbuf, OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN)) + return -EINVAL; + + ocfs2_control_set_handshake_state(file, + OCFS2_CONTROL_HANDSHAKE_PROTOCOL); + + return count; +} + +static void ocfs2_control_send_down(const char *uuid, + int nodenum) +{ + struct ocfs2_live_connection *c; + + mutex_lock(&ocfs2_control_lock); + + c = ocfs2_connection_find(uuid); + if (c) { + BUG_ON(c->oc_conn == NULL); + c->oc_conn->cc_recovery_handler(nodenum, + c->oc_conn->cc_recovery_data); + } + + mutex_unlock(&ocfs2_control_lock); +} + +/* + * Called whenever configuration elements are sent to /dev/ocfs2_control. + * If all configuration elements are present, try to set the global + * values. If there is a problem, return an error. Skip any missing + * elements, and only bump ocfs2_control_opened when we have all elements + * and are successful. + */ +static int ocfs2_control_install_private(struct file *file) +{ + int rc = 0; + int set_p = 1; + struct ocfs2_control_private *p = file->private_data; + + BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL); + + mutex_lock(&ocfs2_control_lock); + + if (p->op_this_node < 0) { + set_p = 0; + } else if ((ocfs2_control_this_node >= 0) && + (ocfs2_control_this_node != p->op_this_node)) { + rc = -EINVAL; + goto out_unlock; + } + + if (!p->op_proto.pv_major) { + set_p = 0; + } else if (!list_empty(&ocfs2_live_connection_list) && + ((running_proto.pv_major != p->op_proto.pv_major) || + (running_proto.pv_minor != p->op_proto.pv_minor))) { + rc = -EINVAL; + goto out_unlock; + } + + if (set_p) { + ocfs2_control_this_node = p->op_this_node; + running_proto.pv_major = p->op_proto.pv_major; + running_proto.pv_minor = p->op_proto.pv_minor; + atomic_inc(&ocfs2_control_opened); + ocfs2_control_set_handshake_state(file, + OCFS2_CONTROL_HANDSHAKE_VALID); + } + +out_unlock: + mutex_unlock(&ocfs2_control_lock); + + return rc; +} + +static int ocfs2_control_get_this_node(void) +{ + int rc; + + mutex_lock(&ocfs2_control_lock); + if (ocfs2_control_this_node < 0) + rc = -EINVAL; + else + rc = ocfs2_control_this_node; + mutex_unlock(&ocfs2_control_lock); + + return rc; +} + +static int ocfs2_control_do_setnode_msg(struct file *file, + struct ocfs2_control_message_setn *msg) +{ + long nodenum; + struct ocfs2_control_private *p = file->private_data; + + if (ocfs2_control_get_handshake_state(file) != + OCFS2_CONTROL_HANDSHAKE_PROTOCOL) + return -EINVAL; + + if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + return -EINVAL; + + if ((msg->space != ' ') || (msg->newline != '\n')) + return -EINVAL; + msg->space = msg->newline = '\0'; + + if (kstrtol(msg->nodestr, 16, &nodenum)) + return -EINVAL; + + if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) || + (nodenum > INT_MAX) || (nodenum < 0)) + return -ERANGE; + p->op_this_node = nodenum; + + return ocfs2_control_install_private(file); +} + +static int ocfs2_control_do_setversion_msg(struct file *file, + struct ocfs2_control_message_setv *msg) +{ + long major, minor; + struct ocfs2_control_private *p = file->private_data; + struct ocfs2_protocol_version *max = + &ocfs2_user_plugin.sp_max_proto; + + if (ocfs2_control_get_handshake_state(file) != + OCFS2_CONTROL_HANDSHAKE_PROTOCOL) + return -EINVAL; + + if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + return -EINVAL; + + if ((msg->space1 != ' ') || (msg->space2 != ' ') || + (msg->newline != '\n')) + return -EINVAL; + msg->space1 = msg->space2 = msg->newline = '\0'; + + if (kstrtol(msg->major, 16, &major)) + return -EINVAL; + if (kstrtol(msg->minor, 16, &minor)) + return -EINVAL; + + /* + * The major must be between 1 and 255, inclusive. The minor + * must be between 0 and 255, inclusive. The version passed in + * must be within the maximum version supported by the filesystem. + */ + if ((major == LONG_MIN) || (major == LONG_MAX) || + (major > (u8)-1) || (major < 1)) + return -ERANGE; + if ((minor == LONG_MIN) || (minor == LONG_MAX) || + (minor > (u8)-1) || (minor < 0)) + return -ERANGE; + if ((major != max->pv_major) || + (minor > max->pv_minor)) + return -EINVAL; + + p->op_proto.pv_major = major; + p->op_proto.pv_minor = minor; + + return ocfs2_control_install_private(file); +} + +static int ocfs2_control_do_down_msg(struct file *file, + struct ocfs2_control_message_down *msg) +{ + long nodenum; + + if (ocfs2_control_get_handshake_state(file) != + OCFS2_CONTROL_HANDSHAKE_VALID) + return -EINVAL; + + if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_DOWN_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + return -EINVAL; + + if ((msg->space1 != ' ') || (msg->space2 != ' ') || + (msg->newline != '\n')) + return -EINVAL; + msg->space1 = msg->space2 = msg->newline = '\0'; + + if (kstrtol(msg->nodestr, 16, &nodenum)) + return -EINVAL; + + if ((nodenum == LONG_MIN) || (nodenum == LONG_MAX) || + (nodenum > INT_MAX) || (nodenum < 0)) + return -ERANGE; + + ocfs2_control_send_down(msg->uuid, nodenum); + + return 0; +} + +static ssize_t ocfs2_control_message(struct file *file, + const char __user *buf, + size_t count) +{ + ssize_t ret; + union ocfs2_control_message msg; + + /* Try to catch padding issues */ + WARN_ON(offsetof(struct ocfs2_control_message_down, uuid) != + (sizeof(msg.u_down.tag) + sizeof(msg.u_down.space1))); + + memset(&msg, 0, sizeof(union ocfs2_control_message)); + ret = ocfs2_control_cfu(&msg, count, buf, count); + if (ret) + goto out; + + if ((count == OCFS2_CONTROL_MESSAGE_SETNODE_TOTAL_LEN) && + !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETNODE_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + ret = ocfs2_control_do_setnode_msg(file, &msg.u_setn); + else if ((count == OCFS2_CONTROL_MESSAGE_SETVERSION_TOTAL_LEN) && + !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_SETVERSION_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + ret = ocfs2_control_do_setversion_msg(file, &msg.u_setv); + else if ((count == OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN) && + !strncmp(msg.tag, OCFS2_CONTROL_MESSAGE_DOWN_OP, + OCFS2_CONTROL_MESSAGE_OP_LEN)) + ret = ocfs2_control_do_down_msg(file, &msg.u_down); + else + ret = -EINVAL; + +out: + return ret ? ret : count; +} + +static ssize_t ocfs2_control_write(struct file *file, + const char __user *buf, + size_t count, + loff_t *ppos) +{ + ssize_t ret; + + switch (ocfs2_control_get_handshake_state(file)) { + case OCFS2_CONTROL_HANDSHAKE_INVALID: + ret = -EINVAL; + break; + + case OCFS2_CONTROL_HANDSHAKE_READ: + ret = ocfs2_control_validate_protocol(file, buf, + count); + break; + + case OCFS2_CONTROL_HANDSHAKE_PROTOCOL: + case OCFS2_CONTROL_HANDSHAKE_VALID: + ret = ocfs2_control_message(file, buf, count); + break; + + default: + BUG(); + ret = -EIO; + break; + } + + return ret; +} + +/* + * This is a naive version. If we ever have a new protocol, we'll expand + * it. Probably using seq_file. + */ +static ssize_t ocfs2_control_read(struct file *file, + char __user *buf, + size_t count, + loff_t *ppos) +{ + ssize_t ret; + + ret = simple_read_from_buffer(buf, count, ppos, + OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN); + + /* Have we read the whole protocol list? */ + if (ret > 0 && *ppos >= OCFS2_CONTROL_PROTO_LEN) + ocfs2_control_set_handshake_state(file, + OCFS2_CONTROL_HANDSHAKE_READ); + + return ret; +} + +static int ocfs2_control_release(struct inode *inode, struct file *file) +{ + struct ocfs2_control_private *p = file->private_data; + + mutex_lock(&ocfs2_control_lock); + + if (ocfs2_control_get_handshake_state(file) != + OCFS2_CONTROL_HANDSHAKE_VALID) + goto out; + + if (atomic_dec_and_test(&ocfs2_control_opened)) { + if (!list_empty(&ocfs2_live_connection_list)) { + /* XXX: Do bad things! */ + printk(KERN_ERR + "ocfs2: Unexpected release of ocfs2_control!\n" + " Loss of cluster connection requires " + "an emergency restart!\n"); + emergency_restart(); + } + /* + * Last valid close clears the node number and resets + * the locking protocol version + */ + ocfs2_control_this_node = -1; + running_proto.pv_major = 0; + running_proto.pv_minor = 0; + } + +out: + list_del_init(&p->op_list); + file->private_data = NULL; + + mutex_unlock(&ocfs2_control_lock); + + kfree(p); + + return 0; +} + +static int ocfs2_control_open(struct inode *inode, struct file *file) +{ + struct ocfs2_control_private *p; + + p = kzalloc_obj(struct ocfs2_control_private); + if (!p) + return -ENOMEM; + p->op_this_node = -1; + + mutex_lock(&ocfs2_control_lock); + file->private_data = p; + list_add(&p->op_list, &ocfs2_control_private_list); + mutex_unlock(&ocfs2_control_lock); + + return 0; +} + +static const struct file_operations ocfs2_control_fops = { + .open = ocfs2_control_open, + .release = ocfs2_control_release, + .read = ocfs2_control_read, + .write = ocfs2_control_write, + .owner = THIS_MODULE, + .llseek = default_llseek, +}; + +static struct miscdevice ocfs2_control_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "ocfs2_control", + .fops = &ocfs2_control_fops, +}; + +static int ocfs2_control_init(void) +{ + int rc; + + atomic_set(&ocfs2_control_opened, 0); + + rc = misc_register(&ocfs2_control_device); + if (rc) + printk(KERN_ERR + "ocfs2: Unable to register ocfs2_control device " + "(errno %d)\n", + -rc); + + return rc; +} + +static void ocfs2_control_exit(void) +{ + misc_deregister(&ocfs2_control_device); +} + +static void fsdlm_lock_ast_wrapper(void *astarg) +{ + struct ocfs2_dlm_lksb *lksb = astarg; + int status = lksb->lksb_fsdlm.sb_status; + + /* + * For now we're punting on the issue of other non-standard errors + * where we can't tell if the unlock_ast or lock_ast should be called. + * The main "other error" that's possible is EINVAL which means the + * function was called with invalid args, which shouldn't be possible + * since the caller here is under our control. Other non-standard + * errors probably fall into the same category, or otherwise are fatal + * which means we can't carry on anyway. + */ + + if (status == -DLM_EUNLOCK || status == -DLM_ECANCEL) + lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, 0); + else + lksb->lksb_conn->cc_proto->lp_lock_ast(lksb); +} + +static void fsdlm_blocking_ast_wrapper(void *astarg, int level) +{ + struct ocfs2_dlm_lksb *lksb = astarg; + + lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level); +} + +static int user_dlm_lock(struct ocfs2_cluster_connection *conn, + int mode, + struct ocfs2_dlm_lksb *lksb, + u32 flags, + void *name, + unsigned int namelen) +{ + if (!lksb->lksb_fsdlm.sb_lvbptr) + lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb + + sizeof(struct dlm_lksb); + + return dlm_lock(conn->cc_lockspace, mode, &lksb->lksb_fsdlm, + flags|DLM_LKF_NODLCKWT, name, namelen, 0, + fsdlm_lock_ast_wrapper, lksb, + fsdlm_blocking_ast_wrapper); +} + +static int user_dlm_unlock(struct ocfs2_cluster_connection *conn, + struct ocfs2_dlm_lksb *lksb, + u32 flags) +{ + return dlm_unlock(conn->cc_lockspace, lksb->lksb_fsdlm.sb_lkid, + flags, &lksb->lksb_fsdlm, lksb); +} + +static int user_dlm_lock_status(struct ocfs2_dlm_lksb *lksb) +{ + return lksb->lksb_fsdlm.sb_status; +} + +static int user_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb) +{ + int invalid = lksb->lksb_fsdlm.sb_flags & DLM_SBF_VALNOTVALID; + + return !invalid; +} + +static void *user_dlm_lvb(struct ocfs2_dlm_lksb *lksb) +{ + if (!lksb->lksb_fsdlm.sb_lvbptr) + lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb + + sizeof(struct dlm_lksb); + return (void *)(lksb->lksb_fsdlm.sb_lvbptr); +} + +static void user_dlm_dump_lksb(struct ocfs2_dlm_lksb *lksb) +{ +} + +static int user_plock(struct ocfs2_cluster_connection *conn, + u64 ino, + struct file *file, + int cmd, + struct file_lock *fl) +{ + /* + * This more or less just demuxes the plock request into any + * one of three dlm calls. + * + * Internally, fs/dlm will pass these to a misc device, which + * a userspace daemon will read and write to. + */ + + if (cmd == F_CANCELLK) + return dlm_posix_cancel(conn->cc_lockspace, ino, file, fl); + else if (IS_GETLK(cmd)) + return dlm_posix_get(conn->cc_lockspace, ino, file, fl); + else if (lock_is_unlock(fl)) + return dlm_posix_unlock(conn->cc_lockspace, ino, file, fl); + else + return dlm_posix_lock(conn->cc_lockspace, ino, file, cmd, fl); +} + +/* + * Compare a requested locking protocol version against the current one. + * + * If the major numbers are different, they are incompatible. + * If the current minor is greater than the request, they are incompatible. + * If the current minor is less than or equal to the request, they are + * compatible, and the requester should run at the current minor version. + */ +static int fs_protocol_compare(struct ocfs2_protocol_version *existing, + struct ocfs2_protocol_version *request) +{ + if (existing->pv_major != request->pv_major) + return 1; + + if (existing->pv_minor > request->pv_minor) + return 1; + + if (existing->pv_minor < request->pv_minor) + request->pv_minor = existing->pv_minor; + + return 0; +} + +static void lvb_to_version(char *lvb, struct ocfs2_protocol_version *ver) +{ + struct ocfs2_protocol_version *pv = + (struct ocfs2_protocol_version *)lvb; + /* + * ocfs2_protocol_version has two u8 variables, so we don't + * need any endian conversion. + */ + ver->pv_major = pv->pv_major; + ver->pv_minor = pv->pv_minor; +} + +static void version_to_lvb(struct ocfs2_protocol_version *ver, char *lvb) +{ + struct ocfs2_protocol_version *pv = + (struct ocfs2_protocol_version *)lvb; + /* + * ocfs2_protocol_version has two u8 variables, so we don't + * need any endian conversion. + */ + pv->pv_major = ver->pv_major; + pv->pv_minor = ver->pv_minor; +} + +static void sync_wait_cb(void *arg) +{ + struct ocfs2_cluster_connection *conn = arg; + struct ocfs2_live_connection *lc = conn->cc_private; + complete(&lc->oc_sync_wait); +} + +static int sync_unlock(struct ocfs2_cluster_connection *conn, + struct dlm_lksb *lksb, char *name) +{ + int error; + struct ocfs2_live_connection *lc = conn->cc_private; + + error = dlm_unlock(conn->cc_lockspace, lksb->sb_lkid, 0, lksb, conn); + if (error) { + printk(KERN_ERR "%s lkid %x error %d\n", + name, lksb->sb_lkid, error); + return error; + } + + wait_for_completion(&lc->oc_sync_wait); + + if (lksb->sb_status != -DLM_EUNLOCK) { + printk(KERN_ERR "%s lkid %x status %d\n", + name, lksb->sb_lkid, lksb->sb_status); + return -1; + } + return 0; +} + +static int sync_lock(struct ocfs2_cluster_connection *conn, + int mode, uint32_t flags, + struct dlm_lksb *lksb, char *name) +{ + int error, status; + struct ocfs2_live_connection *lc = conn->cc_private; + + error = dlm_lock(conn->cc_lockspace, mode, lksb, flags, + name, strlen(name), + 0, sync_wait_cb, conn, NULL); + if (error) { + printk(KERN_ERR "%s lkid %x flags %x mode %d error %d\n", + name, lksb->sb_lkid, flags, mode, error); + return error; + } + + wait_for_completion(&lc->oc_sync_wait); + + status = lksb->sb_status; + + if (status && status != -EAGAIN) { + printk(KERN_ERR "%s lkid %x flags %x mode %d status %d\n", + name, lksb->sb_lkid, flags, mode, status); + } + + return status; +} + + +static int version_lock(struct ocfs2_cluster_connection *conn, int mode, + int flags) +{ + struct ocfs2_live_connection *lc = conn->cc_private; + return sync_lock(conn, mode, flags, + &lc->oc_version_lksb, VERSION_LOCK); +} + +static int version_unlock(struct ocfs2_cluster_connection *conn) +{ + struct ocfs2_live_connection *lc = conn->cc_private; + return sync_unlock(conn, &lc->oc_version_lksb, VERSION_LOCK); +} + +/* get_protocol_version() + * + * To exchange ocfs2 versioning, we use the LVB of the version dlm lock. + * The algorithm is: + * 1. Attempt to take the lock in EX mode (non-blocking). + * 2. If successful (which means it is the first mount), write the + * version number and downconvert to PR lock. + * 3. If unsuccessful (returns -EAGAIN), read the version from the LVB after + * taking the PR lock. + */ + +static int get_protocol_version(struct ocfs2_cluster_connection *conn) +{ + int ret; + struct ocfs2_live_connection *lc = conn->cc_private; + struct ocfs2_protocol_version pv; + + running_proto.pv_major = + ocfs2_user_plugin.sp_max_proto.pv_major; + running_proto.pv_minor = + ocfs2_user_plugin.sp_max_proto.pv_minor; + + lc->oc_version_lksb.sb_lvbptr = lc->oc_lvb; + ret = version_lock(conn, DLM_LOCK_EX, + DLM_LKF_VALBLK|DLM_LKF_NOQUEUE); + if (!ret) { + conn->cc_version.pv_major = running_proto.pv_major; + conn->cc_version.pv_minor = running_proto.pv_minor; + version_to_lvb(&running_proto, lc->oc_lvb); + version_lock(conn, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_VALBLK); + } else if (ret == -EAGAIN) { + ret = version_lock(conn, DLM_LOCK_PR, DLM_LKF_VALBLK); + if (ret) + goto out; + lvb_to_version(lc->oc_lvb, &pv); + + if ((pv.pv_major != running_proto.pv_major) || + (pv.pv_minor > running_proto.pv_minor)) { + ret = -EINVAL; + goto out; + } + + conn->cc_version.pv_major = pv.pv_major; + conn->cc_version.pv_minor = pv.pv_minor; + } +out: + return ret; +} + +static void user_recover_prep(void *arg) +{ +} + +static void user_recover_slot(void *arg, struct dlm_slot *slot) +{ + struct ocfs2_cluster_connection *conn = arg; + printk(KERN_INFO "ocfs2: Node %d/%d down. Initiating recovery.\n", + slot->nodeid, slot->slot); + conn->cc_recovery_handler(slot->nodeid, conn->cc_recovery_data); + +} + +static void user_recover_done(void *arg, struct dlm_slot *slots, + int num_slots, int our_slot, + uint32_t generation) +{ + struct ocfs2_cluster_connection *conn = arg; + struct ocfs2_live_connection *lc = conn->cc_private; + int i; + + for (i = 0; i < num_slots; i++) + if (slots[i].slot == our_slot) { + atomic_set(&lc->oc_this_node, slots[i].nodeid); + break; + } + + lc->oc_our_slot = our_slot; + wake_up(&lc->oc_wait); +} + +static const struct dlm_lockspace_ops ocfs2_ls_ops = { + .recover_prep = user_recover_prep, + .recover_slot = user_recover_slot, + .recover_done = user_recover_done, +}; + +static int user_cluster_disconnect(struct ocfs2_cluster_connection *conn) +{ + version_unlock(conn); + dlm_release_lockspace(conn->cc_lockspace, DLM_RELEASE_NORMAL); + conn->cc_lockspace = NULL; + ocfs2_live_connection_drop(conn->cc_private); + conn->cc_private = NULL; + return 0; +} + +static int user_cluster_connect(struct ocfs2_cluster_connection *conn) +{ + dlm_lockspace_t *fsdlm; + struct ocfs2_live_connection *lc; + int rc, ops_rv; + + BUG_ON(conn == NULL); + + lc = kzalloc_obj(struct ocfs2_live_connection); + if (!lc) + return -ENOMEM; + + init_waitqueue_head(&lc->oc_wait); + init_completion(&lc->oc_sync_wait); + atomic_set(&lc->oc_this_node, 0); + conn->cc_private = lc; + lc->oc_type = NO_CONTROLD; + + rc = dlm_new_lockspace(conn->cc_name, conn->cc_cluster_name, + DLM_LSFL_NEWEXCL, DLM_LVB_LEN, + &ocfs2_ls_ops, conn, &ops_rv, &fsdlm); + if (rc) { + if (rc == -EEXIST || rc == -EPROTO) + printk(KERN_ERR "ocfs2: Unable to create the " + "lockspace %s (%d), because a ocfs2-tools " + "program is running on this file system " + "with the same name lockspace\n", + conn->cc_name, rc); + goto out; + } + + if (ops_rv == -EOPNOTSUPP) { + lc->oc_type = WITH_CONTROLD; + printk(KERN_NOTICE "ocfs2: You seem to be using an older " + "version of dlm_controld and/or ocfs2-tools." + " Please consider upgrading.\n"); + } else if (ops_rv) { + rc = ops_rv; + goto out; + } + conn->cc_lockspace = fsdlm; + + rc = ocfs2_live_connection_attach(conn, lc); + if (rc) + goto out; + + if (lc->oc_type == NO_CONTROLD) { + rc = get_protocol_version(conn); + if (rc) { + printk(KERN_ERR "ocfs2: Could not determine" + " locking version\n"); + user_cluster_disconnect(conn); + lc = NULL; + goto out; + } + wait_event(lc->oc_wait, (atomic_read(&lc->oc_this_node) > 0)); + } + + /* + * running_proto must have been set before we allowed any mounts + * to proceed. + */ + if (fs_protocol_compare(&running_proto, &conn->cc_version)) { + printk(KERN_ERR + "Unable to mount with fs locking protocol version " + "%u.%u because negotiated protocol is %u.%u\n", + conn->cc_version.pv_major, conn->cc_version.pv_minor, + running_proto.pv_major, running_proto.pv_minor); + rc = -EPROTO; + ocfs2_live_connection_drop(lc); + lc = NULL; + } + +out: + if (rc) + kfree(lc); + return rc; +} + + +static int user_cluster_this_node(struct ocfs2_cluster_connection *conn, + unsigned int *this_node) +{ + int rc; + struct ocfs2_live_connection *lc = conn->cc_private; + + if (lc->oc_type == WITH_CONTROLD) + rc = ocfs2_control_get_this_node(); + else if (lc->oc_type == NO_CONTROLD) + rc = atomic_read(&lc->oc_this_node); + else + rc = -EINVAL; + + if (rc < 0) + return rc; + + *this_node = rc; + return 0; +} + +static const struct ocfs2_stack_operations ocfs2_user_plugin_ops = { + .connect = user_cluster_connect, + .disconnect = user_cluster_disconnect, + .this_node = user_cluster_this_node, + .dlm_lock = user_dlm_lock, + .dlm_unlock = user_dlm_unlock, + .lock_status = user_dlm_lock_status, + .lvb_valid = user_dlm_lvb_valid, + .lock_lvb = user_dlm_lvb, + .plock = user_plock, + .dump_lksb = user_dlm_dump_lksb, +}; + +static struct ocfs2_stack_plugin ocfs2_user_plugin = { + .sp_name = "user", + .sp_ops = &ocfs2_user_plugin_ops, + .sp_owner = THIS_MODULE, +}; + + +static int __init ocfs2_user_plugin_init(void) +{ + int rc; + + rc = ocfs2_control_init(); + if (!rc) { + rc = ocfs2_stack_glue_register(&ocfs2_user_plugin); + if (rc) + ocfs2_control_exit(); + } + + return rc; +} + +static void __exit ocfs2_user_plugin_exit(void) +{ + ocfs2_stack_glue_unregister(&ocfs2_user_plugin); + ocfs2_control_exit(); +} + +MODULE_AUTHOR("Oracle"); +MODULE_DESCRIPTION("ocfs2 driver for userspace cluster stacks"); +MODULE_LICENSE("GPL"); +module_init(ocfs2_user_plugin_init); +module_exit(ocfs2_user_plugin_exit); -- cgit v1.3.1