[Ocfs2-devel] [PATCH 5/5] Remove control data structures and functions
Goldwyn Rodrigues
rgoldwyn at suse.de
Wed Aug 21 06:10:48 PDT 2013
Signed-off-by: Goldwyn Rodrigues <rgoldwyn at suse.com>
---
fs/ocfs2/stack_user.c | 664 +-------------------------------------------------
1 file changed, 1 insertion(+), 663 deletions(-)
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index b869d4d6..e15aa98 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -30,645 +30,14 @@
#include <linux/dlm_plock.h>
-/*
- * 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<space><8-char-hex-nodenum><newline>
- *
- * 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<space><2-char-hex-major><space><2-char-hex-minor><newline>
- *
- * 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<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline>
- *
- * 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
-
-/*
- * 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;
-};
-
struct ocfs2_connection_private {
atomic_t cp_this_node;
int cp_our_slot;
wait_queue_head_t cp_wait;
};
-struct ocfs2_control_private {
- struct list_head op_list;
- int op_state;
- int op_this_node;
- struct ocfs2_protocol_version op_proto;
-};
-
-/* SETN<space><8-char-hex-nodenum><newline> */
-struct ocfs2_control_message_setn {
- char tag[OCFS2_CONTROL_MESSAGE_OP_LEN];
- char space;
- char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
- char newline;
-};
-
-/* SETV<space><2-char-hex-major><space><2-char-hex-minor><newline> */
-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<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
-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_new(struct ocfs2_cluster_connection *conn,
- struct ocfs2_live_connection **c_ret)
-{
- int rc = 0;
- struct ocfs2_live_connection *c;
-
- c = kzalloc(sizeof(struct ocfs2_live_connection), GFP_KERNEL);
- if (!c)
- return -ENOMEM;
-
- mutex_lock(&ocfs2_control_lock);
- c->oc_conn = conn;
-
- if (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);
-
- if (!rc)
- *c_ret = c;
- else
- kfree(c);
-
- 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;
- }
-
-out_unlock:
- mutex_unlock(&ocfs2_control_lock);
-
- if (!rc && set_p) {
- /* We set the global values successfully */
- atomic_inc(&ocfs2_control_opened);
- ocfs2_control_set_handshake_state(file,
- OCFS2_CONTROL_HANDSHAKE_VALID);
- }
-
- 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;
- char *ptr = NULL;
- 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';
-
- nodenum = simple_strtol(msg->nodestr, &ptr, 16);
- if (!ptr || *ptr)
- 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;
- char *ptr = NULL;
- 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';
-
- major = simple_strtol(msg->major, &ptr, 16);
- if (!ptr || *ptr)
- return -EINVAL;
- minor = simple_strtol(msg->minor, &ptr, 16);
- if (!ptr || *ptr)
- 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;
- char *p = NULL;
-
- 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';
-
- nodenum = simple_strtol(msg->nodestr, &p, 16);
- if (!p || *p)
- 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_major = 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(sizeof(struct ocfs2_control_private), GFP_KERNEL);
- 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)
-{
- int rc;
-
- rc = misc_deregister(&ocfs2_control_device);
- if (rc)
- printk(KERN_ERR
- "ocfs2: Unable to deregister ocfs2_control device "
- "(errno %d)\n",
- -rc);
-}
-
static void fsdlm_lock_ast_wrapper(void *astarg)
{
struct ocfs2_dlm_lksb *lksb = astarg;
@@ -783,29 +152,6 @@ static int user_plock(struct ocfs2_cluster_connection *conn,
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 user_recover_prep(void *arg)
{
}
@@ -926,21 +272,13 @@ static struct ocfs2_stack_plugin ocfs2_user_plugin = {
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();
- }
-
+ rc = ocfs2_stack_glue_register(&ocfs2_user_plugin);
return rc;
}
static void __exit ocfs2_user_plugin_exit(void)
{
ocfs2_stack_glue_unregister(&ocfs2_user_plugin);
- ocfs2_control_exit();
}
MODULE_AUTHOR("Oracle");
--
1.8.1.4
--
Goldwyn
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