um: resurrect the right variant of mconsole_proc() (723a1d77) · Commits · e / devices / android_kernel_fairphone_FP3

arch/um/drivers/mconsole_kern.c

+21 −78

Original line number	Diff line number	Diff line
		@@ -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 @@ 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 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 @@ void mconsole_proc(struct mc_request *req)
		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 @@ void mconsole_proc(struct mc_request *req)
		goto out_fput;
		}

		if (file->f_op->read) {
		do {
		loff_t pos;
		mm_segment_t old_fs = get_fs();
		set_fs(KERNEL_DS);
		n = vfs_read(file, buf, PAGE_SIZE - 1, &pos);
		file_pos_write(file, pos);
		len = vfs_read(file, buf, PAGE_SIZE - 1, &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);
		file->f_pos = pos;
		if (len < 0) {
		mconsole_reply(req, "Read of file failed", 1, 0);
		goto out_free;
		@@ -211,22 +162,14 @@ void mconsole_proc(struct mc_request *req)
		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;
		}
		}

		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 \