diff options
| -rw-r--r-- | arch/um/drivers/mconsole_kern.c | 87 |
1 files changed, 81 insertions, 6 deletions
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index b5217bd7bc41..e9bbc14f3655 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -20,6 +20,7 @@ #include "linux/namei.h" #include "linux/proc_fs.h" #include "linux/syscalls.h" +#include "linux/console.h" #include "asm/irq.h" #include "asm/uaccess.h" #include "user_util.h" @@ -480,6 +481,82 @@ void mconsole_sysrq(struct mc_request *req) } #endif +static DEFINE_SPINLOCK(console_lock); +static LIST_HEAD(clients); +static char console_buf[MCONSOLE_MAX_DATA]; +static int console_index = 0; + +static void console_write(struct console *console, const char *string, + unsigned len) +{ + struct list_head *ele; + int n; + + if(list_empty(&clients)) + return; + + while(1){ + n = min(len, ARRAY_SIZE(console_buf) - console_index); + strncpy(&console_buf[console_index], string, n); + console_index += n; + string += n; + len -= n; + if(len == 0) + return; + + list_for_each(ele, &clients){ + struct mconsole_entry *entry; + + entry = list_entry(ele, struct mconsole_entry, list); + mconsole_reply_len(&entry->request, console_buf, + console_index, 0, 1); + } + + console_index = 0; + } +} + +static struct console mc_console = { .name = "mc", + .write = console_write, + .flags = CON_PRINTBUFFER | CON_ENABLED, + .index = -1 }; + +static int mc_add_console(void) +{ + register_console(&mc_console); + return 0; +} + +late_initcall(mc_add_console); + +static void with_console(struct mc_request *req, void (*proc)(void *), + void *arg) +{ + struct mconsole_entry entry; + unsigned long flags; + + INIT_LIST_HEAD(&entry.list); + entry.request = *req; + list_add(&entry.list, &clients); + spin_lock_irqsave(&console_lock, flags); + + (*proc)(arg); + + mconsole_reply_len(req, console_buf, console_index, 0, 0); + console_index = 0; + + spin_unlock_irqrestore(&console_lock, flags); + list_del(&entry.list); +} + +static void stack_proc(void *arg) +{ + struct task_struct *from = current, *to = arg; + + to->thread.saved_task = from; + switch_to(from, to, from); +} + /* Mconsole stack trace * Added by Allan Graves, Jeff Dike * Dumps a stacks registers to the linux console. @@ -489,7 +566,7 @@ void do_stack(struct mc_request *req) { char *ptr = req->request.data; int pid_requested= -1; - struct task_struct *from = NULL; + struct task_struct *from = NULL; struct task_struct *to = NULL; /* Would be nice: @@ -507,17 +584,15 @@ void do_stack(struct mc_request *req) return; } - from = current; - to = find_task_by_pid(pid_requested); + from = current; + to = find_task_by_pid(pid_requested); if((to == NULL) || (pid_requested == 0)) { mconsole_reply(req, "Couldn't find that pid", 1, 0); return; } - to->thread.saved_task = current; - switch_to(from, to, from); - mconsole_reply(req, "Stack Dumped to console and message log", 0, 0); + with_console(req, stack_proc, to); } void mconsole_stack(struct mc_request *req) |