Added the proc command.

A bit of code cleanup.

3 files changed, 104 insertions, 13 deletions

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index f587abb..2292f5d 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -15,6 +15,8 @@
 #include "linux/sysrq.h"
 #include "linux/tqueue.h"
 #include "linux/module.h"
+#include "linux/file.h"
+#include "linux/fs.h"
 #include "linux/proc_fs.h"
 #include "asm/irq.h"
 #include "asm/uaccess.h"
@@ -79,7 +81,8 @@ void mconsole_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 
 	fd = (int) dev_id;
 	while (mconsole_get_request(fd, &req)){
-		if(req.cmd->as_interrupt) (*req.cmd->handler)(&req);
+		if(req.cmd->context == MCONSOLE_INTR) 
+			(*req.cmd->handler)(&req);
 		else {
 			new = kmalloc(sizeof(req), GFP_ATOMIC);
 			if(new == NULL)
@@ -117,6 +120,90 @@ void mconsole_log(struct mc_request *req)
 	mconsole_reply(req, "", 0, 0);
 }
 
+void mconsole_proc(struct mc_request *req)
+{
+	struct nameidata nd;
+	struct file_system_type *proc;
+	struct super_block *super;
+	struct file *file;
+	int n, err;
+	char *ptr = req->request.data, *buf;
+	
+	ptr += strlen("proc");
+	while(isspace(*ptr)) ptr++;
+
+	proc = get_fs_type("proc");
+	if(proc == NULL){
+		mconsole_reply(req, "procfs not registered", 1, 0);
+		goto out;
+	}
+
+	super = get_anon_super(proc, NULL, NULL);
+	if(super == NULL){
+		mconsole_reply(req, "Failed to get procfs superblock", 1, 0);
+		goto out_put;
+	}
+
+	if(super->s_root == NULL){
+		super = (*proc->read_super)(super, NULL, 0);
+		if(super == NULL){
+			mconsole_reply(req, "Failed to read superblock", 1, 0);
+			goto out_put;
+		}
+	}
+	up_write(&super->s_umount);
+
+	nd.dentry = super->s_root;
+	nd.mnt = NULL;
+	nd.flags = O_RDONLY + 1;
+	nd.last_type = LAST_ROOT;
+
+	err = link_path_walk(ptr, &nd);
+	if(err){
+		mconsole_reply(req, "Failed to look up file", 1, 0);
+		goto out_kill;
+	}
+
+	file = dentry_open(nd.dentry, nd.mnt, O_RDONLY);
+	if(IS_ERR(file)){
+		mconsole_reply(req, "Failed to open file", 1, 0);
+		goto out_kill;
+	}
+
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if(buf == NULL){
+		mconsole_reply(req, "Failed to allocate buffer", 1, 0);
+		goto out_fput;
+	}
+
+	if((file->f_op != NULL) && (file->f_op->read != NULL)){
+		do {
+			n = (*file->f_op->read)(file, buf, PAGE_SIZE - 1, 
+						&file->f_pos);
+			if(n >= 0){
+				buf[n] = '\0';
+				mconsole_reply(req, buf, 0, (n > 0));
+			}
+			else {
+				mconsole_reply(req, "Read of file failed", 
+					       1, 0);
+				goto out_free;
+			}
+		} while(n > 0);
+	}
+	else mconsole_reply(req, "", 0, 0);
+
+ out_free:
+	kfree(buf);
+ out_fput:
+	fput(file);
+ out_kill:
+	kill_super(super);
+ out_put:
+	/* put_filesystem(proc); */
+ out: ;
+}
+
 #define UML_MCONSOLE_HELPTEXT \
 "Commands: \n\
     version - Get kernel version \n\
diff --git a/arch/um/drivers/mconsole_user.c b/arch/um/drivers/mconsole_user.c
index f9fcbc6..08c1074 100644
--- a/arch/um/drivers/mconsole_user.c
+++ b/arch/um/drivers/mconsole_user.c
@@ -18,17 +18,18 @@
 #include "umid.h"
 
 static struct mconsole_command commands[] = {
-	{ "version", mconsole_version, 1 },
-	{ "halt", mconsole_halt, 0 },
-	{ "reboot", mconsole_reboot, 0 },
-	{ "config", mconsole_config, 0 },
-	{ "remove", mconsole_remove, 0 },
-	{ "sysrq", mconsole_sysrq, 1 },
-	{ "help", mconsole_help, 1 },
-	{ "cad", mconsole_cad, 1 },
-	{ "stop", mconsole_stop, 0 },
-	{ "go", mconsole_go, 1 },
-	{ "log", mconsole_log, 1 },
+	{ "version", mconsole_version, MCONSOLE_INTR },
+	{ "halt", mconsole_halt, MCONSOLE_PROC },
+	{ "reboot", mconsole_reboot, MCONSOLE_PROC },
+	{ "config", mconsole_config, MCONSOLE_PROC },
+	{ "remove", mconsole_remove, MCONSOLE_PROC },
+	{ "sysrq", mconsole_sysrq, MCONSOLE_INTR },
+	{ "help", mconsole_help, MCONSOLE_INTR },
+	{ "cad", mconsole_cad, MCONSOLE_INTR },
+	{ "stop", mconsole_stop, MCONSOLE_PROC },
+	{ "go", mconsole_go, MCONSOLE_INTR },
+	{ "log", mconsole_log, MCONSOLE_INTR },
+	{ "proc", mconsole_proc, MCONSOLE_PROC },
 };
 
 /* Initialized in mconsole_init, which is an initcall */
diff --git a/arch/um/include/mconsole.h b/arch/um/include/mconsole.h
index 14ccb3a..9fbe308 100644
--- a/arch/um/include/mconsole.h
+++ b/arch/um/include/mconsole.h
@@ -41,11 +41,13 @@ struct mconsole_notify {
 
 struct mc_request;
 
+enum mc_context { MCONSOLE_INTR, MCONSOLE_PROC };
+
 struct mconsole_command
 {
 	char *command;
 	void (*handler)(struct mc_request *req);
-	int as_interrupt;
+	enum mc_context context;
 };
 
 struct mc_request
@@ -78,6 +80,7 @@ extern void mconsole_cad(struct mc_request *req);
 extern void mconsole_stop(struct mc_request *req);
 extern void mconsole_go(struct mc_request *req);
 extern void mconsole_log(struct mc_request *req);
+extern void mconsole_proc(struct mc_request *req);
 
 extern int mconsole_get_request(int fd, struct mc_request *req);
 extern int mconsole_notify(char *sock_name, int type, const void *data,