Commit 1329c204 authored by Linus Torvalds's avatar Linus Torvalds
Browse files
Pull sparc updates from David Miller:

 - a FPE signal fix that was also merged upstream

 - privileged ADI driver from Tom Hromatka

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: fix compat siginfo ABI regression
  selftests: sparc64: char: Selftest for privileged ADI driver
  char: sparc64: Add privileged ADI driver
parents d6c75284 1c1ff29d
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+12 −0
Original line number Diff line number Diff line
@@ -540,5 +540,17 @@ source "drivers/s390/char/Kconfig"

source "drivers/char/xillybus/Kconfig"

config ADI
	tristate "SPARC Privileged ADI driver"
	depends on SPARC64
	default m
	help
	  SPARC M7 and newer processors utilize ADI (Application Data
	  Integrity) to version and protect memory.  This driver provides
	  read/write access to the ADI versions for privileged processes.
	  This feature is also known as MCD (Memory Corruption Detection)
	  and SSM (Silicon Secured Memory).  Intended consumers of this
	  driver include crash and makedumpfile.

endmenu
+1 −0
Original line number Diff line number Diff line
@@ -57,3 +57,4 @@ js-rtc-y = rtc.o

obj-$(CONFIG_XILLYBUS)		+= xillybus/
obj-$(CONFIG_POWERNV_OP_PANEL)	+= powernv-op-panel.o
obj-$(CONFIG_ADI)		+= adi.o

drivers/char/adi.c

0 → 100644
+239 −0
Original line number Diff line number Diff line
// SPDX-License-Identifier: GPL-2.0
/*
 * Privileged ADI driver for sparc64
 *
 * Author: Tom Hromatka <tom.hromatka@oracle.com>
 */
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <asm/asi.h>

#define MAX_BUF_SZ	PAGE_SIZE

static int adi_open(struct inode *inode, struct file *file)
{
	file->f_mode |= FMODE_UNSIGNED_OFFSET;
	return 0;
}

static int read_mcd_tag(unsigned long addr)
{
	long err;
	int ver;

	__asm__ __volatile__(
		"1:	ldxa [%[addr]] %[asi], %[ver]\n"
		"	mov 0, %[err]\n"
		"2:\n"
		"	.section .fixup,#alloc,#execinstr\n"
		"	.align 4\n"
		"3:	sethi %%hi(2b), %%g1\n"
		"	jmpl  %%g1 + %%lo(2b), %%g0\n"
		"	mov %[invalid], %[err]\n"
		"	.previous\n"
		"	.section __ex_table, \"a\"\n"
		"	.align 4\n"
		"	.word  1b, 3b\n"
		"	.previous\n"
		: [ver] "=r" (ver), [err] "=r" (err)
		: [addr] "r"  (addr), [invalid] "i" (EFAULT),
		  [asi] "i" (ASI_MCD_REAL)
		: "memory", "g1"
		);

	if (err)
		return -EFAULT;
	else
		return ver;
}

static ssize_t adi_read(struct file *file, char __user *buf,
			size_t count, loff_t *offp)
{
	size_t ver_buf_sz, bytes_read = 0;
	int ver_buf_idx = 0;
	loff_t offset;
	u8 *ver_buf;
	ssize_t ret;

	ver_buf_sz = min_t(size_t, count, MAX_BUF_SZ);
	ver_buf = kmalloc(ver_buf_sz, GFP_KERNEL);
	if (!ver_buf)
		return -ENOMEM;

	offset = (*offp) * adi_blksize();

	while (bytes_read < count) {
		ret = read_mcd_tag(offset);
		if (ret < 0)
			goto out;

		ver_buf[ver_buf_idx] = (u8)ret;
		ver_buf_idx++;
		offset += adi_blksize();

		if (ver_buf_idx >= ver_buf_sz) {
			if (copy_to_user(buf + bytes_read, ver_buf,
					 ver_buf_sz)) {
				ret = -EFAULT;
				goto out;
			}

			bytes_read += ver_buf_sz;
			ver_buf_idx = 0;

			ver_buf_sz = min(count - bytes_read,
					 (size_t)MAX_BUF_SZ);
		}
	}

	(*offp) += bytes_read;
	ret = bytes_read;
out:
	kfree(ver_buf);
	return ret;
}

static int set_mcd_tag(unsigned long addr, u8 ver)
{
	long err;

	__asm__ __volatile__(
		"1:	stxa %[ver], [%[addr]] %[asi]\n"
		"	mov 0, %[err]\n"
		"2:\n"
		"	.section .fixup,#alloc,#execinstr\n"
		"	.align 4\n"
		"3:	sethi %%hi(2b), %%g1\n"
		"	jmpl %%g1 + %%lo(2b), %%g0\n"
		"	mov %[invalid], %[err]\n"
		"	.previous\n"
		"	.section __ex_table, \"a\"\n"
		"	.align 4\n"
		"	.word 1b, 3b\n"
		"	.previous\n"
		: [err] "=r" (err)
		: [ver] "r" (ver), [addr] "r"  (addr),
		  [invalid] "i" (EFAULT), [asi] "i" (ASI_MCD_REAL)
		: "memory", "g1"
		);

	if (err)
		return -EFAULT;
	else
		return ver;
}

static ssize_t adi_write(struct file *file, const char __user *buf,
			 size_t count, loff_t *offp)
{
	size_t ver_buf_sz, bytes_written = 0;
	loff_t offset;
	u8 *ver_buf;
	ssize_t ret;
	int i;

	if (count <= 0)
		return -EINVAL;

	ver_buf_sz = min_t(size_t, count, MAX_BUF_SZ);
	ver_buf = kmalloc(ver_buf_sz, GFP_KERNEL);
	if (!ver_buf)
		return -ENOMEM;

	offset = (*offp) * adi_blksize();

	do {
		if (copy_from_user(ver_buf, &buf[bytes_written],
				   ver_buf_sz)) {
			ret = -EFAULT;
			goto out;
		}

		for (i = 0; i < ver_buf_sz; i++) {
			ret = set_mcd_tag(offset, ver_buf[i]);
			if (ret < 0)
				goto out;

			offset += adi_blksize();
		}

		bytes_written += ver_buf_sz;
		ver_buf_sz = min(count - bytes_written, (size_t)MAX_BUF_SZ);
	} while (bytes_written < count);

	(*offp) += bytes_written;
	ret = bytes_written;
out:
	__asm__ __volatile__("membar #Sync");
	kfree(ver_buf);
	return ret;
}

static loff_t adi_llseek(struct file *file, loff_t offset, int whence)
{
	loff_t ret = -EINVAL;

	switch (whence) {
	case SEEK_END:
	case SEEK_DATA:
	case SEEK_HOLE:
		/* unsupported */
		return -EINVAL;
	case SEEK_CUR:
		if (offset == 0)
			return file->f_pos;

		offset += file->f_pos;
		break;
	case SEEK_SET:
		break;
	}

	if (offset != file->f_pos) {
		file->f_pos = offset;
		file->f_version = 0;
		ret = offset;
	}

	return ret;
}

static const struct file_operations adi_fops = {
	.owner		= THIS_MODULE,
	.llseek		= adi_llseek,
	.open		= adi_open,
	.read		= adi_read,
	.write		= adi_write,
};

static struct miscdevice adi_miscdev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = KBUILD_MODNAME,
	.fops = &adi_fops,
};

static int __init adi_init(void)
{
	if (!adi_capable())
		return -EPERM;

	return misc_register(&adi_miscdev);
}

static void __exit adi_exit(void)
{
	misc_deregister(&adi_miscdev);
}

module_init(adi_init);
module_exit(adi_exit);

MODULE_AUTHOR("Tom Hromatka <tom.hromatka@oracle.com>");
MODULE_DESCRIPTION("Privileged interface to ADI");
MODULE_VERSION("1.0");
MODULE_LICENSE("GPL v2");
+1 −0
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ TARGETS += rtc
TARGETS += seccomp
TARGETS += sigaltstack
TARGETS += size
TARGETS += sparc64
TARGETS += splice
TARGETS += static_keys
TARGETS += sync
+46 −0
Original line number Diff line number Diff line
SUBDIRS := drivers

TEST_PROGS := run.sh

.PHONY: all clean

include ../lib.mk

all:
	@for DIR in $(SUBDIRS); do		\
		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
		mkdir $$BUILD_TARGET  -p;	\
		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
		#SUBDIR test prog name should be in the form: SUBDIR_test.sh \
		TEST=$$DIR"_test.sh"; \
		if [ -e $$DIR/$$TEST ]; then \
			rsync -a $$DIR/$$TEST $$BUILD_TARGET/; \
		fi \
	done

override define RUN_TESTS
	@cd $(OUTPUT); ./run.sh
endef

override define INSTALL_RULE
	mkdir -p $(INSTALL_PATH)
	install -t $(INSTALL_PATH) $(TEST_PROGS) $(TEST_PROGS_EXTENDED) $(TEST_FILES)

	@for SUBDIR in $(SUBDIRS); do \
		BUILD_TARGET=$(OUTPUT)/$$SUBDIR;	\
		mkdir $$BUILD_TARGET  -p;	\
		$(MAKE) OUTPUT=$$BUILD_TARGET -C $$SUBDIR INSTALL_PATH=$(INSTALL_PATH)/$$SUBDIR install; \
	done;
endef

override define EMIT_TESTS
	echo "./run.sh"
endef

override define CLEAN
	@for DIR in $(SUBDIRS); do		\
		BUILD_TARGET=$(OUTPUT)/$$DIR;	\
		mkdir $$BUILD_TARGET  -p;	\
		make OUTPUT=$$BUILD_TARGET -C $$DIR $@;\
	done
endef
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