vserver 1.9.5.x5

[linux-2.6.git] / arch / um / drivers / mconsole_kern.c

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 9076c06..d7c7adc 100644 (file)
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -19,6 +19,7 @@
 #include "linux/fs.h"
 #include "linux/namei.h"
 #include "linux/proc_fs.h"
+#include "linux/syscalls.h"
 #include "asm/irq.h"
 #include "asm/uaccess.h"
 #include "user_util.h"
@@ -72,11 +73,12 @@ DECLARE_WORK(mconsole_work, mc_work_proc, NULL);
 static irqreturn_t mconsole_interrupt(int irq, void *dev_id,
                                      struct pt_regs *regs)
 {
-       int fd;
+       /* long to avoid size mismatch warnings from gcc */
+       long fd;
        struct mconsole_entry *new;
        struct mc_request req;
 
-       fd = (int) dev_id;
+       fd = (long) dev_id;
        while (mconsole_get_request(fd, &req)){
                if(req.cmd->context == MCONSOLE_INTR)
                        (*req.cmd->handler)(&req);
@@ -118,6 +120,11 @@ void mconsole_log(struct mc_request *req)
        mconsole_reply(req, "", 0, 0);
 }
 
+/* This is a more convoluted version of mconsole_proc, which has some stability
+ * problems; however, we need it fixed, because it is expected that UML users
+ * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still
+ * show the real procfs content, not the ones from hppfs.*/
+#if 0
 void mconsole_proc(struct mc_request *req)
 {
        struct nameidata nd;
@@ -149,6 +156,9 @@ void mconsole_proc(struct mc_request *req)
        nd.flags = O_RDONLY + 1;
        nd.last_type = LAST_ROOT;
 
+       /* START: it was experienced that the stability problems are closed
+        * if commenting out these two calls + the below read cycle. To
+        * make UML crash again, it was enough to readd either one.*/
        err = link_path_walk(ptr, &nd);
        if(err){
                mconsole_reply(req, "Failed to look up file", 1, 0);
@@ -160,6 +170,7 @@ void mconsole_proc(struct mc_request *req)
                mconsole_reply(req, "Failed to open file", 1, 0);
                goto out_kill;
        }
+       /*END*/
 
        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
        if(buf == NULL){
@@ -192,6 +203,62 @@ void mconsole_proc(struct mc_request *req)
        deactivate_super(super);
  out: ;
 }
+#endif
+
+void mconsole_proc(struct mc_request *req)
+{
+       char path[64];
+       char *buf;
+       int len;
+       int fd;
+       int first_chunk = 1;
+       char *ptr = req->request.data;
+
+       ptr += strlen("proc");
+       while(isspace(*ptr)) ptr++;
+       snprintf(path, sizeof(path), "/proc/%s", ptr);
+
+       fd = sys_open(path, 0, 0);
+       if (fd < 0) {
+               mconsole_reply(req, "Failed to open file", 1, 0);
+               printk("open %s: %d\n",path,fd);
+               goto out;
+       }
+
+       buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+       if(buf == NULL){
+               mconsole_reply(req, "Failed to allocate buffer", 1, 0);
+               goto out_close;
+       }
+
+       for (;;) {
+               len = sys_read(fd, buf, PAGE_SIZE-1);
+               if (len < 0) {
+                       mconsole_reply(req, "Read of file failed", 1, 0);
+                       goto out_free;
+               }
+               /*Begin the file content on his own line.*/
+               if (first_chunk) {
+                       mconsole_reply(req, "\n", 0, 1);
+                       first_chunk = 0;
+               }
+               if (len == PAGE_SIZE-1) {
+                       buf[len] = '\0';
+                       mconsole_reply(req, buf, 0, 1);
+               } else {
+                       buf[len] = '\0';
+                       mconsole_reply(req, buf, 0, 0);
+                       break;
+               }
+       }
+
+ out_free:
+       kfree(buf);
+ out_close:
+       sys_close(fd);
+ out:
+       /* nothing */;
+}
 
 #define UML_MCONSOLE_HELPTEXT \
 "Commands: \n\
@@ -391,7 +458,9 @@ static char *notify_socket = NULL;
 
 int mconsole_init(void)
 {
-       int err, sock;
+       /* long to avoid size mismatch warnings from gcc */
+       long sock;
+       int err;
        char file[256];
 
        if(umid_file_name("mconsole", file, sizeof(file))) return(-1);
@@ -430,7 +499,7 @@ int mconsole_init(void)
 
 __initcall(mconsole_init);
 
-static int write_proc_mconsole(struct file *file, const char *buffer,
+static int write_proc_mconsole(struct file *file, const char __user *buffer,
                               unsigned long count, void *data)
 {
        char *buf;
@@ -469,7 +538,7 @@ static int create_proc_mconsole(void)
        return(0);
 }
 
-static spinlock_t notify_spinlock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(notify_spinlock);
 
 void lock_notify(void)
 {