X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fum%2Fdrivers%2Fmconsole_kern.c;h=e4d9bb9fa89347cb29b3766f5fb603be1e504fde;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=d7c7adcc0a6731a2acec59eceffdb18a949ffcad;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index d7c7adcc0..e4d9bb9fa 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -20,6 +20,10 @@ #include "linux/namei.h" #include "linux/proc_fs.h" #include "linux/syscalls.h" +#include "linux/list.h" +#include "linux/mm.h" +#include "linux/console.h" +#include "linux/vs_cvirt.h" #include "asm/irq.h" #include "asm/uaccess.h" #include "user_util.h" @@ -32,8 +36,9 @@ #include "os.h" #include "umid.h" #include "irq_kern.h" +#include "choose-mode.h" -static int do_unlink_socket(struct notifier_block *notifier, +static int do_unlink_socket(struct notifier_block *notifier, unsigned long what, void *data) { return(mconsole_unlink_socket()); @@ -45,12 +50,12 @@ static struct notifier_block reboot_notifier = { .priority = 0, }; -/* Safe without explicit locking for now. Tasklets provide their own +/* Safe without explicit locking for now. Tasklets provide their own * locking, and the interrupt handler is safe because it can't interrupt * itself and it can only happen on CPU 0. */ -LIST_HEAD(mc_requests); +static LIST_HEAD(mc_requests); static void mc_work_proc(void *unused) { @@ -58,8 +63,8 @@ static void mc_work_proc(void *unused) unsigned long flags; while(!list_empty(&mc_requests)){ - local_save_flags(flags); - req = list_entry(mc_requests.next, struct mconsole_entry, + local_irq_save(flags); + req = list_entry(mc_requests.next, struct mconsole_entry, list); list_del(&req->list); local_irq_restore(flags); @@ -68,7 +73,7 @@ static void mc_work_proc(void *unused) } } -DECLARE_WORK(mconsole_work, mc_work_proc, NULL); +static DECLARE_WORK(mconsole_work, mc_work_proc, NULL); static irqreturn_t mconsole_interrupt(int irq, void *dev_id, struct pt_regs *regs) @@ -83,7 +88,7 @@ static irqreturn_t mconsole_interrupt(int irq, void *dev_id, if(req.cmd->context == MCONSOLE_INTR) (*req.cmd->handler)(&req); else { - new = kmalloc(sizeof(*new), GFP_ATOMIC); + new = kmalloc(sizeof(*new), GFP_NOWAIT); if(new == NULL) mconsole_reply(&req, "Out of memory", 1, 0); else { @@ -102,8 +107,8 @@ void mconsole_version(struct mc_request *req) { char version[256]; - sprintf(version, "%s %s %s %s %s", system_utsname.sysname, - system_utsname.nodename, system_utsname.release, + sprintf(version, "%s %s %s %s %s", system_utsname.sysname, + system_utsname.nodename, system_utsname.release, system_utsname.version, system_utsname.machine); mconsole_reply(req, version, 0, 0); } @@ -271,11 +276,12 @@ void mconsole_proc(struct mc_request *req) config - Query the configuration of a device \n\ remove - Remove a device from UML \n\ sysrq - Performs the SysRq action controlled by the letter \n\ - cad - invoke the Ctl-Alt-Del handler \n\ + cad - invoke the Ctrl-Alt-Del handler \n\ stop - pause the UML; it will do nothing until it receives a 'go' \n\ go - continue the UML after a 'stop' \n\ log - make UML enter into the kernel log\n\ proc - returns the contents of the UML's /proc/\n\ + stack - returns the stack of the specified pid\n\ " void mconsole_help(struct mc_request *req) @@ -324,7 +330,7 @@ void mconsole_stop(struct mc_request *req) /* This list is populated by __initcall routines. */ -LIST_HEAD(mconsole_devices); +static LIST_HEAD(mconsole_devices); void mconsole_register_dev(struct mc_device *new) { @@ -344,9 +350,144 @@ static struct mc_device *mconsole_find_dev(char *name) return(NULL); } +#define UNPLUGGED_PER_PAGE \ + ((PAGE_SIZE - sizeof(struct list_head)) / sizeof(unsigned long)) + +struct unplugged_pages { + struct list_head list; + void *pages[UNPLUGGED_PER_PAGE]; +}; + +static unsigned long long unplugged_pages_count = 0; +static struct list_head unplugged_pages = LIST_HEAD_INIT(unplugged_pages); +static int unplug_index = UNPLUGGED_PER_PAGE; + +static int mem_config(char *str) +{ + unsigned long long diff; + int err = -EINVAL, i, add; + char *ret; + + if(str[0] != '=') + goto out; + + str++; + if(str[0] == '-') + add = 0; + else if(str[0] == '+'){ + add = 1; + } + else goto out; + + str++; + diff = memparse(str, &ret); + if(*ret != '\0') + goto out; + + diff /= PAGE_SIZE; + + for(i = 0; i < diff; i++){ + struct unplugged_pages *unplugged; + void *addr; + + if(add){ + if(list_empty(&unplugged_pages)) + break; + + unplugged = list_entry(unplugged_pages.next, + struct unplugged_pages, list); + if(unplug_index > 0) + addr = unplugged->pages[--unplug_index]; + else { + list_del(&unplugged->list); + addr = unplugged; + unplug_index = UNPLUGGED_PER_PAGE; + } + + free_page((unsigned long) addr); + unplugged_pages_count--; + } + else { + struct page *page; + + page = alloc_page(GFP_ATOMIC); + if(page == NULL) + break; + + unplugged = page_address(page); + if(unplug_index == UNPLUGGED_PER_PAGE){ + list_add(&unplugged->list, &unplugged_pages); + unplug_index = 0; + } + else { + struct list_head *entry = unplugged_pages.next; + addr = unplugged; + + unplugged = list_entry(entry, + struct unplugged_pages, + list); + unplugged->pages[unplug_index++] = addr; + err = os_drop_memory(addr, PAGE_SIZE); + if(err) + printk("Failed to release memory - " + "errno = %d\n", err); + } + + unplugged_pages_count++; + } + } + + err = 0; +out: + return err; +} + +static int mem_get_config(char *name, char *str, int size, char **error_out) +{ + char buf[sizeof("18446744073709551615")]; + int len = 0; + + sprintf(buf, "%ld", uml_physmem); + CONFIG_CHUNK(str, size, len, buf, 1); + + return len; +} + +static int mem_id(char **str, int *start_out, int *end_out) +{ + *start_out = 0; + *end_out = 0; + + return 0; +} + +static int mem_remove(int n) +{ + return -EBUSY; +} + +static struct mc_device mem_mc = { + .name = "mem", + .config = mem_config, + .get_config = mem_get_config, + .id = mem_id, + .remove = mem_remove, +}; + +static int mem_mc_init(void) +{ + if(can_drop_memory()) + mconsole_register_dev(&mem_mc); + else printk("Can't release memory to the host - memory hotplug won't " + "be supported\n"); + return 0; +} + +__initcall(mem_mc_init); + #define CONFIG_BUF_SIZE 64 -static void mconsole_get_config(int (*get_config)(char *, char *, int, +static void mconsole_get_config(int (*get_config)(char *, char *, int, char **), struct mc_request *req, char *name) { @@ -387,7 +528,6 @@ static void mconsole_get_config(int (*get_config)(char *, char *, int, out: if(buf != default_buf) kfree(buf); - } void mconsole_config(struct mc_request *req) @@ -418,9 +558,10 @@ void mconsole_config(struct mc_request *req) void mconsole_remove(struct mc_request *req) { - struct mc_device *dev; - char *ptr = req->request.data; - int err; + struct mc_device *dev; + char *ptr = req->request.data, *err_msg = ""; + char error[256]; + int err, start, end, n; ptr += strlen("remove"); while(isspace(*ptr)) ptr++; @@ -429,11 +570,112 @@ void mconsole_remove(struct mc_request *req) mconsole_reply(req, "Bad remove option", 1, 0); return; } - err = (*dev->remove)(&ptr[strlen(dev->name)]); - mconsole_reply(req, "", err, 0); + + ptr = &ptr[strlen(dev->name)]; + + err = 1; + n = (*dev->id)(&ptr, &start, &end); + if(n < 0){ + err_msg = "Couldn't parse device number"; + goto out; + } + else if((n < start) || (n > end)){ + sprintf(error, "Invalid device number - must be between " + "%d and %d", start, end); + err_msg = error; + goto out; + } + + err = (*dev->remove)(n); + switch(err){ + case -ENODEV: + err_msg = "Device doesn't exist"; + break; + case -EBUSY: + err_msg = "Device is currently open"; + break; + default: + break; + } +out: + mconsole_reply(req, err_msg, err, 0); +} + +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((size_t) 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_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; + + 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); } #ifdef CONFIG_MAGIC_SYSRQ +static void sysrq_proc(void *arg) +{ + char *op = arg; + + handle_sysrq(*op, ¤t->thread.regs, NULL); +} + void mconsole_sysrq(struct mc_request *req) { char *ptr = req->request.data; @@ -441,8 +683,13 @@ void mconsole_sysrq(struct mc_request *req) ptr += strlen("sysrq"); while(isspace(*ptr)) ptr++; - mconsole_reply(req, "", 0, 0); - handle_sysrq(*ptr, ¤t->thread.regs, NULL); + /* With 'b', the system will shut down without a chance to reply, + * so in this case, we reply first. + */ + if(*ptr == 'b') + mconsole_reply(req, "", 0, 0); + + with_console(req, sysrq_proc, ptr); } #else void mconsole_sysrq(struct mc_request *req) @@ -451,12 +698,70 @@ void mconsole_sysrq(struct mc_request *req) } #endif +#ifdef CONFIG_MODE_SKAS + +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. + * Usage stack . + */ +static void do_stack_trace(struct mc_request *req) +{ + char *ptr = req->request.data; + int pid_requested= -1; + struct task_struct *from = NULL; + struct task_struct *to = NULL; + + /* Would be nice: + * 1) Send showregs output to mconsole. + * 2) Add a way to stack dump all pids. + */ + + ptr += strlen("stack"); + while(isspace(*ptr)) ptr++; + + /* Should really check for multiple pids or reject bad args here */ + /* What do the arguments in mconsole_reply mean? */ + if(sscanf(ptr, "%d", &pid_requested) == 0){ + mconsole_reply(req, "Please specify a pid", 1, 0); + return; + } + + 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; + } + with_console(req, stack_proc, to); +} +#endif /* CONFIG_MODE_SKAS */ + +void mconsole_stack(struct mc_request *req) +{ + /* This command doesn't work in TT mode, so let's check and then + * get out of here + */ + CHOOSE_MODE(mconsole_reply(req, "Sorry, this doesn't work in TT mode", + 1, 0), + do_stack_trace(req)); +} + /* Changed by mconsole_setup, which is __setup, and called before SMP is * active. */ -static char *notify_socket = NULL; +static char *notify_socket = NULL; -int mconsole_init(void) +static int mconsole_init(void) { /* long to avoid size mismatch warnings from gcc */ long sock; @@ -483,16 +788,16 @@ int mconsole_init(void) } if(notify_socket != NULL){ - notify_socket = uml_strdup(notify_socket); + notify_socket = kstrdup(notify_socket, GFP_KERNEL); if(notify_socket != NULL) mconsole_notify(notify_socket, MCONSOLE_SOCKET, - mconsole_socket_name, + mconsole_socket_name, strlen(mconsole_socket_name) + 1); else printk(KERN_ERR "mconsole_setup failed to strdup " "string\n"); } - printk("mconsole (version %d) initialized on %s\n", + printk("mconsole (version %d) initialized on %s\n", MCONSOLE_VERSION, mconsole_socket_name); return(0); } @@ -505,7 +810,7 @@ static int write_proc_mconsole(struct file *file, const char __user *buffer, char *buf; buf = kmalloc(count + 1, GFP_KERNEL); - if(buf == NULL) + if(buf == NULL) return(-ENOMEM); if(copy_from_user(buf, buffer, count)){ @@ -529,7 +834,7 @@ static int create_proc_mconsole(void) ent = create_proc_entry("mconsole", S_IFREG | 0200, NULL); if(ent == NULL){ - printk("create_proc_mconsole : create_proc_entry failed\n"); + printk(KERN_INFO "create_proc_mconsole : create_proc_entry failed\n"); return(0); } @@ -581,7 +886,7 @@ static int notify_panic(struct notifier_block *self, unsigned long unused1, if(notify_socket == NULL) return(0); - mconsole_notify(notify_socket, MCONSOLE_PANIC, message, + mconsole_notify(notify_socket, MCONSOLE_PANIC, message, strlen(message) + 1); return(0); } @@ -594,7 +899,8 @@ static struct notifier_block panic_exit_notifier = { static int add_notifier(void) { - notifier_chain_register(&panic_notifier_list, &panic_exit_notifier); + atomic_notifier_chain_register(&panic_notifier_list, + &panic_exit_notifier); return(0); } @@ -606,14 +912,3 @@ char *mconsole_notify_socket(void) } EXPORT_SYMBOL(mconsole_notify_socket); - -/* - * Overrides for Emacs so that we follow Linus's tabbing style. - * Emacs will notice this stuff at the end of the file and automatically - * adjust the settings for this buffer only. This must remain at the end - * of the file. - * --------------------------------------------------------------------------- - * Local variables: - * c-file-style: "linux" - * End: - */