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yaml
---
r: 89568
b: refs/heads/master
c: 3cfd4ab
h: refs/heads/master
v: v3
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Joel Becker authored and Mark Fasheh committed Apr 18, 2008
1 parent a1a655b commit 750eba2
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Showing 2 changed files with 174 additions and 50 deletions.
2 changes: 1 addition & 1 deletion [refs]
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Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: de870ef02295c9f5601dbf2efdc1be6df44b187b
refs/heads/master: 3cfd4ab6b6b4bee2035b62e1c293801c3d257502
222 changes: 173 additions & 49 deletions trunk/fs/ocfs2/stack_user.c
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Original file line number Diff line number Diff line change
Expand Up @@ -40,8 +40,18 @@
* unknown, -EINVAL is returned. Once the negotiation is complete, the
* client can start sending messages.
*
* The T01 protocol only has one message, "DOWN". It has the following
* syntax:
* The T01 protocol only has two 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.
*
* Once the local node number has been set, 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>
*
Expand All @@ -58,11 +68,18 @@
*/
#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_VALID (2)
#define OCFS2_CONTROL_MESSAGE_DOWN "DOWN"
#define OCFS2_CONTROL_MESSAGE_DOWN_LEN 4
#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_DOWN_OP "DOWN"
#define OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN 47
#define OCFS2_TEXT_UUID_LEN 32
#define OCFS2_CONTROL_MESSAGE_NODENUM_LEN 8
Expand All @@ -79,9 +96,35 @@ struct ocfs2_live_connection {
struct ocfs2_control_private {
struct list_head op_list;
int op_state;
int op_this_node;
};

/* 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;
};

/* 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_down u_down;
};

static atomic_t ocfs2_control_opened;
static int ocfs2_control_this_node = -1;

static LIST_HEAD(ocfs2_live_connection_list);
static LIST_HEAD(ocfs2_control_private_list);
Expand Down Expand Up @@ -166,38 +209,37 @@ static void ocfs2_live_connection_drop(struct ocfs2_live_connection *c)
kfree(c);
}

static ssize_t ocfs2_control_cfu(void *target, size_t target_len,
const char __user *buf, size_t count)
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)
if ((count != target_len) ||
(count > sizeof(union ocfs2_control_message)))
return -EINVAL;

if (copy_from_user(target, buf, target_len))
return -EFAULT;

return count;
return 0;
}

static ssize_t ocfs2_control_validate_handshake(struct file *file,
const char __user *buf,
size_t count)
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 != count)
if (ret)
return ret;

if (strncmp(kbuf, OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN))
return -EINVAL;

atomic_inc(&ocfs2_control_opened);
ocfs2_control_set_handshake_state(file,
OCFS2_CONTROL_HANDSHAKE_VALID);

OCFS2_CONTROL_HANDSHAKE_PROTOCOL);

return count;
}
Expand All @@ -219,55 +261,133 @@ static void ocfs2_control_send_down(const char *uuid,
mutex_unlock(&ocfs2_control_lock);
}

/* DOWN<space><32-char-cap-hex-uuid><space><8-char-hex-nodenum><newline> */
struct ocfs2_control_message_down {
char tag[OCFS2_CONTROL_MESSAGE_DOWN_LEN];
char space1;
char uuid[OCFS2_TEXT_UUID_LEN];
char space2;
char nodestr[OCFS2_CONTROL_MESSAGE_NODENUM_LEN];
char newline;
};
/*
* Called whenever configuration elements are sent to /dev/ocfs2_control.
* If all configuration elements are present, try to set the global
* values. If not, return -EAGAIN. If there is a problem, return a
* different error.
*/
static int ocfs2_control_install_private(struct file *file)
{
int rc = 0;
int set_p = 1;
struct ocfs2_control_private *p = file->private_data;

static ssize_t ocfs2_control_message(struct file *file,
const char __user *buf,
size_t count)
BUG_ON(p->op_state != OCFS2_CONTROL_HANDSHAKE_PROTOCOL);

if (p->op_this_node < 0)
set_p = 0;

mutex_lock(&ocfs2_control_lock);
if (ocfs2_control_this_node < 0) {
if (set_p)
ocfs2_control_this_node = p->op_this_node;
} else if (ocfs2_control_this_node != p->op_this_node)
rc = -EINVAL;
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_do_setnode_msg(struct file *file,
struct ocfs2_control_message_setn *msg)
{
ssize_t ret;
char *p = NULL;
long nodenum;
struct ocfs2_control_message_down msg;
char *ptr = NULL;
struct ocfs2_control_private *p = file->private_data;

/* Try to catch padding issues */
WARN_ON(offsetof(struct ocfs2_control_message_down, uuid) !=
(sizeof(msg.tag) + sizeof(msg.space1)));
if (ocfs2_control_get_handshake_state(file) !=
OCFS2_CONTROL_HANDSHAKE_PROTOCOL)
return -EINVAL;

memset(&msg, 0, sizeof(struct ocfs2_control_message_down));
ret = ocfs2_control_cfu(&msg, OCFS2_CONTROL_MESSAGE_DOWN_TOTAL_LEN,
buf, count);
if (ret != count)
return ret;
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_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,
strlen(OCFS2_CONTROL_MESSAGE_DOWN)))
if (strncmp(msg->tag, OCFS2_CONTROL_MESSAGE_DOWN_OP,
OCFS2_CONTROL_MESSAGE_OP_LEN))
return -EINVAL;

if ((msg.space1 != ' ') || (msg.space2 != ' ') ||
(msg.newline != '\n'))
if ((msg->space1 != ' ') || (msg->space2 != ' ') ||
(msg->newline != '\n'))
return -EINVAL;
msg.space1 = msg.space2 = msg.newline = '\0';
msg->space1 = msg->space2 = msg->newline = '\0';

nodenum = simple_strtol(msg.nodestr, &p, 16);
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);
ocfs2_control_send_down(msg->uuid, nodenum);

return count;
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_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,
Expand All @@ -283,10 +403,11 @@ static ssize_t ocfs2_control_write(struct file *file,
break;

case OCFS2_CONTROL_HANDSHAKE_READ:
ret = ocfs2_control_validate_handshake(file, buf,
count);
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;
Expand Down Expand Up @@ -350,6 +471,8 @@ static int ocfs2_control_release(struct inode *inode, struct file *file)
"an emergency restart!\n");
emergency_restart();
}
/* Last valid close clears the node number */
ocfs2_control_this_node = -1;
}

out:
Expand All @@ -370,6 +493,7 @@ static int ocfs2_control_open(struct inode *inode, struct file *file)
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;
Expand Down

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