um: resurrect the right variant of mconsole_proc()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 664a60e..495e5a7 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -21,6 +21,9 @@
#include <linux/un.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/file.h>
#include <asm/uaccess.h>
#include <asm/switch_to.h>
@@ -118,18 +121,14 @@
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 vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt;
+ char *buf;
+ int len;
struct file *file;
- int n;
- char *ptr = req->request.data, *buf;
- mm_segment_t old_fs = get_fs();
+ int first_chunk = 1;
+ char *ptr = req->request.data;
ptr += strlen("proc");
ptr = skip_spaces(ptr);
@@ -137,6 +136,7 @@
file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY);
if (IS_ERR(file)) {
mconsole_reply(req, "Failed to open file", 1, 0);
+ printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file));
goto out;
}
@@ -146,62 +146,13 @@
goto out_fput;
}
- if (file->f_op->read) {
- do {
- loff_t pos;
- set_fs(KERNEL_DS);
- n = vfs_read(file, buf, PAGE_SIZE - 1, &pos);
- file_pos_write(file, pos);
- set_fs(old_fs);
- 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: ;
-}
-#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");
- ptr = skip_spaces(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(KERN_ERR "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);
+ do {
+ loff_t pos;
+ mm_segment_t old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ len = vfs_read(file, buf, PAGE_SIZE - 1, &pos);
+ set_fs(old_fs);
+ file->f_pos = pos;
if (len < 0) {
mconsole_reply(req, "Read of file failed", 1, 0);
goto out_free;
@@ -211,22 +162,14 @@
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;
- }
- }
-
+ buf[len] = '\0';
+ mconsole_reply(req, buf, 0, (len > 0));
+ } while (len > 0);
out_free:
kfree(buf);
- out_close:
- sys_close(fd);
- out:
- /* nothing */;
+ out_fput:
+ fput(file);
+ out: ;
}
#define UML_MCONSOLE_HELPTEXT \
