linux/drivers/thunderbolt/debugfs.c
Dan Carpenter 77e4907fa6 thunderbolt: debugfs: Fix uninitialized return in counters_write()
If the first line is in an invalid format then the "ret" value is
uninitialized.  We should return -EINVAL instead.

Fixes: 54e418106c ("thunderbolt: Add debugfs interface")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2020-09-10 19:39:56 +03:00

702 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Debugfs interface
*
* Copyright (C) 2020, Intel Corporation
* Authors: Gil Fine <gil.fine@intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
*/
#include <linux/debugfs.h>
#include <linux/pm_runtime.h>
#include "tb.h"
#define PORT_CAP_PCIE_LEN 1
#define PORT_CAP_POWER_LEN 2
#define PORT_CAP_LANE_LEN 3
#define PORT_CAP_USB3_LEN 5
#define PORT_CAP_DP_LEN 8
#define PORT_CAP_TMU_LEN 8
#define PORT_CAP_BASIC_LEN 9
#define PORT_CAP_USB4_LEN 20
#define SWITCH_CAP_TMU_LEN 26
#define SWITCH_CAP_BASIC_LEN 27
#define PATH_LEN 2
#define COUNTER_SET_LEN 3
#define DEBUGFS_ATTR(__space, __write) \
static int __space ## _open(struct inode *inode, struct file *file) \
{ \
return single_open(file, __space ## _show, inode->i_private); \
} \
\
static const struct file_operations __space ## _fops = { \
.owner = THIS_MODULE, \
.open = __space ## _open, \
.release = single_release, \
.read = seq_read, \
.write = __write, \
.llseek = seq_lseek, \
}
#define DEBUGFS_ATTR_RO(__space) \
DEBUGFS_ATTR(__space, NULL)
#define DEBUGFS_ATTR_RW(__space) \
DEBUGFS_ATTR(__space, __space ## _write)
static struct dentry *tb_debugfs_root;
static void *validate_and_copy_from_user(const void __user *user_buf,
size_t *count)
{
size_t nbytes;
void *buf;
if (!*count)
return ERR_PTR(-EINVAL);
if (!access_ok(user_buf, *count))
return ERR_PTR(-EFAULT);
buf = (void *)get_zeroed_page(GFP_KERNEL);
if (!buf)
return ERR_PTR(-ENOMEM);
nbytes = min_t(size_t, *count, PAGE_SIZE);
if (copy_from_user(buf, user_buf, nbytes)) {
free_page((unsigned long)buf);
return ERR_PTR(-EFAULT);
}
*count = nbytes;
return buf;
}
static bool parse_line(char **line, u32 *offs, u32 *val, int short_fmt_len,
int long_fmt_len)
{
char *token;
u32 v[5];
int ret;
token = strsep(line, "\n");
if (!token)
return false;
/*
* For Adapter/Router configuration space:
* Short format is: offset value\n
* v[0] v[1]
* Long format as produced from the read side:
* offset relative_offset cap_id vs_cap_id value\n
* v[0] v[1] v[2] v[3] v[4]
*
* For Counter configuration space:
* Short format is: offset\n
* v[0]
* Long format as produced from the read side:
* offset relative_offset counter_id value\n
* v[0] v[1] v[2] v[3]
*/
ret = sscanf(token, "%i %i %i %i %i", &v[0], &v[1], &v[2], &v[3], &v[4]);
/* In case of Counters, clear counter, "val" content is NA */
if (ret == short_fmt_len) {
*offs = v[0];
*val = v[short_fmt_len - 1];
return true;
} else if (ret == long_fmt_len) {
*offs = v[0];
*val = v[long_fmt_len - 1];
return true;
}
return false;
}
#if IS_ENABLED(CONFIG_USB4_DEBUGFS_WRITE)
static ssize_t regs_write(struct tb_switch *sw, struct tb_port *port,
const char __user *user_buf, size_t count,
loff_t *ppos)
{
struct tb *tb = sw->tb;
char *line, *buf;
u32 val, offset;
int ret = 0;
buf = validate_and_copy_from_user(user_buf, &count);
if (IS_ERR(buf))
return PTR_ERR(buf);
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out;
}
/* User did hardware changes behind the driver's back */
add_taint(TAINT_USER, LOCKDEP_STILL_OK);
line = buf;
while (parse_line(&line, &offset, &val, 2, 5)) {
if (port)
ret = tb_port_write(port, &val, TB_CFG_PORT, offset, 1);
else
ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 1);
if (ret)
break;
}
mutex_unlock(&tb->lock);
out:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
free_page((unsigned long)buf);
return ret < 0 ? ret : count;
}
static ssize_t port_regs_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
struct seq_file *s = file->private_data;
struct tb_port *port = s->private;
return regs_write(port->sw, port, user_buf, count, ppos);
}
static ssize_t switch_regs_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
struct seq_file *s = file->private_data;
struct tb_switch *sw = s->private;
return regs_write(sw, NULL, user_buf, count, ppos);
}
#define DEBUGFS_MODE 0600
#else
#define port_regs_write NULL
#define switch_regs_write NULL
#define DEBUGFS_MODE 0400
#endif
static int port_clear_all_counters(struct tb_port *port)
{
u32 *buf;
int ret;
buf = kcalloc(COUNTER_SET_LEN * port->config.max_counters, sizeof(u32),
GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = tb_port_write(port, buf, TB_CFG_COUNTERS, 0,
COUNTER_SET_LEN * port->config.max_counters);
kfree(buf);
return ret;
}
static ssize_t counters_write(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos)
{
struct seq_file *s = file->private_data;
struct tb_port *port = s->private;
struct tb_switch *sw = port->sw;
struct tb *tb = port->sw->tb;
char *buf;
int ret;
buf = validate_and_copy_from_user(user_buf, &count);
if (IS_ERR(buf))
return PTR_ERR(buf);
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out;
}
/* If written delimiter only, clear all counters in one shot */
if (buf[0] == '\n') {
ret = port_clear_all_counters(port);
} else {
char *line = buf;
u32 val, offset;
ret = -EINVAL;
while (parse_line(&line, &offset, &val, 1, 4)) {
ret = tb_port_write(port, &val, TB_CFG_COUNTERS,
offset, 1);
if (ret)
break;
}
}
mutex_unlock(&tb->lock);
out:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
free_page((unsigned long)buf);
return ret < 0 ? ret : count;
}
static void cap_show(struct seq_file *s, struct tb_switch *sw,
struct tb_port *port, unsigned int cap, u8 cap_id,
u8 vsec_id, int length)
{
int ret, offset = 0;
while (length > 0) {
int i, dwords = min(length, TB_MAX_CONFIG_RW_LENGTH);
u32 data[TB_MAX_CONFIG_RW_LENGTH];
if (port)
ret = tb_port_read(port, data, TB_CFG_PORT, cap + offset,
dwords);
else
ret = tb_sw_read(sw, data, TB_CFG_SWITCH, cap + offset, dwords);
if (ret) {
seq_printf(s, "0x%04x <not accessible>\n",
cap + offset);
if (dwords > 1)
seq_printf(s, "0x%04x ...\n", cap + offset + 1);
return;
}
for (i = 0; i < dwords; i++) {
seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n",
cap + offset + i, offset + i,
cap_id, vsec_id, data[i]);
}
length -= dwords;
offset += dwords;
}
}
static void port_cap_show(struct tb_port *port, struct seq_file *s,
unsigned int cap)
{
struct tb_cap_any header;
u8 vsec_id = 0;
size_t length;
int ret;
ret = tb_port_read(port, &header, TB_CFG_PORT, cap, 1);
if (ret) {
seq_printf(s, "0x%04x <capability read failed>\n", cap);
return;
}
switch (header.basic.cap) {
case TB_PORT_CAP_PHY:
length = PORT_CAP_LANE_LEN;
break;
case TB_PORT_CAP_TIME1:
length = PORT_CAP_TMU_LEN;
break;
case TB_PORT_CAP_POWER:
length = PORT_CAP_POWER_LEN;
break;
case TB_PORT_CAP_ADAP:
if (tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) {
length = PORT_CAP_PCIE_LEN;
} else if (tb_port_is_dpin(port) || tb_port_is_dpout(port)) {
length = PORT_CAP_DP_LEN;
} else if (tb_port_is_usb3_down(port) ||
tb_port_is_usb3_up(port)) {
length = PORT_CAP_USB3_LEN;
} else {
seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
cap, header.basic.cap);
return;
}
break;
case TB_PORT_CAP_VSE:
if (!header.extended_short.length) {
ret = tb_port_read(port, (u32 *)&header + 1, TB_CFG_PORT,
cap + 1, 1);
if (ret) {
seq_printf(s, "0x%04x <capability read failed>\n",
cap + 1);
return;
}
length = header.extended_long.length;
vsec_id = header.extended_short.vsec_id;
} else {
length = header.extended_short.length;
vsec_id = header.extended_short.vsec_id;
/*
* Ice Lake and Tiger Lake do not implement the
* full length of the capability, only first 32
* dwords so hard-code it here.
*/
if (!vsec_id &&
(tb_switch_is_ice_lake(port->sw) ||
tb_switch_is_tiger_lake(port->sw)))
length = 32;
}
break;
case TB_PORT_CAP_USB4:
length = PORT_CAP_USB4_LEN;
break;
default:
seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
cap, header.basic.cap);
return;
}
cap_show(s, NULL, port, cap, header.basic.cap, vsec_id, length);
}
static void port_caps_show(struct tb_port *port, struct seq_file *s)
{
int cap;
cap = tb_port_next_cap(port, 0);
while (cap > 0) {
port_cap_show(port, s, cap);
cap = tb_port_next_cap(port, cap);
}
}
static int port_basic_regs_show(struct tb_port *port, struct seq_file *s)
{
u32 data[PORT_CAP_BASIC_LEN];
int ret, i;
ret = tb_port_read(port, data, TB_CFG_PORT, 0, ARRAY_SIZE(data));
if (ret)
return ret;
for (i = 0; i < ARRAY_SIZE(data); i++)
seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
return 0;
}
static int port_regs_show(struct seq_file *s, void *not_used)
{
struct tb_port *port = s->private;
struct tb_switch *sw = port->sw;
struct tb *tb = sw->tb;
int ret;
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out_rpm_put;
}
seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
ret = port_basic_regs_show(port, s);
if (ret)
goto out_unlock;
port_caps_show(port, s);
out_unlock:
mutex_unlock(&tb->lock);
out_rpm_put:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
return ret;
}
DEBUGFS_ATTR_RW(port_regs);
static void switch_cap_show(struct tb_switch *sw, struct seq_file *s,
unsigned int cap)
{
struct tb_cap_any header;
int ret, length;
u8 vsec_id = 0;
ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, cap, 1);
if (ret) {
seq_printf(s, "0x%04x <capability read failed>\n", cap);
return;
}
if (header.basic.cap == TB_SWITCH_CAP_VSE) {
if (!header.extended_short.length) {
ret = tb_sw_read(sw, (u32 *)&header + 1, TB_CFG_SWITCH,
cap + 1, 1);
if (ret) {
seq_printf(s, "0x%04x <capability read failed>\n",
cap + 1);
return;
}
length = header.extended_long.length;
} else {
length = header.extended_short.length;
}
vsec_id = header.extended_short.vsec_id;
} else {
if (header.basic.cap == TB_SWITCH_CAP_TMU) {
length = SWITCH_CAP_TMU_LEN;
} else {
seq_printf(s, "0x%04x <unknown capability 0x%02x>\n",
cap, header.basic.cap);
return;
}
}
cap_show(s, sw, NULL, cap, header.basic.cap, vsec_id, length);
}
static void switch_caps_show(struct tb_switch *sw, struct seq_file *s)
{
int cap;
cap = tb_switch_next_cap(sw, 0);
while (cap > 0) {
switch_cap_show(sw, s, cap);
cap = tb_switch_next_cap(sw, cap);
}
}
static int switch_basic_regs_show(struct tb_switch *sw, struct seq_file *s)
{
u32 data[SWITCH_CAP_BASIC_LEN];
size_t dwords;
int ret, i;
/* Only USB4 has the additional registers */
if (tb_switch_is_usb4(sw))
dwords = ARRAY_SIZE(data);
else
dwords = 7;
ret = tb_sw_read(sw, data, TB_CFG_SWITCH, 0, dwords);
if (ret)
return ret;
for (i = 0; i < dwords; i++)
seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
return 0;
}
static int switch_regs_show(struct seq_file *s, void *not_used)
{
struct tb_switch *sw = s->private;
struct tb *tb = sw->tb;
int ret;
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out_rpm_put;
}
seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
ret = switch_basic_regs_show(sw, s);
if (ret)
goto out_unlock;
switch_caps_show(sw, s);
out_unlock:
mutex_unlock(&tb->lock);
out_rpm_put:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
return ret;
}
DEBUGFS_ATTR_RW(switch_regs);
static int path_show_one(struct tb_port *port, struct seq_file *s, int hopid)
{
u32 data[PATH_LEN];
int ret, i;
ret = tb_port_read(port, data, TB_CFG_HOPS, hopid * PATH_LEN,
ARRAY_SIZE(data));
if (ret) {
seq_printf(s, "0x%04x <not accessible>\n", hopid * PATH_LEN);
return ret;
}
for (i = 0; i < ARRAY_SIZE(data); i++) {
seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
hopid * PATH_LEN + i, i, hopid, data[i]);
}
return 0;
}
static int path_show(struct seq_file *s, void *not_used)
{
struct tb_port *port = s->private;
struct tb_switch *sw = port->sw;
struct tb *tb = sw->tb;
int start, i, ret = 0;
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out_rpm_put;
}
seq_puts(s, "# offset relative_offset in_hop_id value\n");
/* NHI and lane adapters have entry for path 0 */
if (tb_port_is_null(port) || tb_port_is_nhi(port)) {
ret = path_show_one(port, s, 0);
if (ret)
goto out_unlock;
}
start = tb_port_is_nhi(port) ? 1 : TB_PATH_MIN_HOPID;
for (i = start; i <= port->config.max_in_hop_id; i++) {
ret = path_show_one(port, s, i);
if (ret)
break;
}
out_unlock:
mutex_unlock(&tb->lock);
out_rpm_put:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
return ret;
}
DEBUGFS_ATTR_RO(path);
static int counter_set_regs_show(struct tb_port *port, struct seq_file *s,
int counter)
{
u32 data[COUNTER_SET_LEN];
int ret, i;
ret = tb_port_read(port, data, TB_CFG_COUNTERS,
counter * COUNTER_SET_LEN, ARRAY_SIZE(data));
if (ret) {
seq_printf(s, "0x%04x <not accessible>\n",
counter * COUNTER_SET_LEN);
return ret;
}
for (i = 0; i < ARRAY_SIZE(data); i++) {
seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
counter * COUNTER_SET_LEN + i, i, counter, data[i]);
}
return 0;
}
static int counters_show(struct seq_file *s, void *not_used)
{
struct tb_port *port = s->private;
struct tb_switch *sw = port->sw;
struct tb *tb = sw->tb;
int i, ret = 0;
pm_runtime_get_sync(&sw->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out;
}
seq_puts(s, "# offset relative_offset counter_id value\n");
for (i = 0; i < port->config.max_counters; i++) {
ret = counter_set_regs_show(port, s, i);
if (ret)
break;
}
mutex_unlock(&tb->lock);
out:
pm_runtime_mark_last_busy(&sw->dev);
pm_runtime_put_autosuspend(&sw->dev);
return ret;
}
DEBUGFS_ATTR_RW(counters);
/**
* tb_switch_debugfs_init() - Add debugfs entries for router
* @sw: Pointer to the router
*
* Adds debugfs directories and files for given router.
*/
void tb_switch_debugfs_init(struct tb_switch *sw)
{
struct dentry *debugfs_dir;
struct tb_port *port;
debugfs_dir = debugfs_create_dir(dev_name(&sw->dev), tb_debugfs_root);
sw->debugfs_dir = debugfs_dir;
debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir, sw,
&switch_regs_fops);
tb_switch_for_each_port(sw, port) {
struct dentry *debugfs_dir;
char dir_name[10];
if (port->disabled)
continue;
if (port->config.type == TB_TYPE_INACTIVE)
continue;
snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
debugfs_dir = debugfs_create_dir(dir_name, sw->debugfs_dir);
debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir,
port, &port_regs_fops);
debugfs_create_file("path", 0400, debugfs_dir, port,
&path_fops);
if (port->config.counters_support)
debugfs_create_file("counters", 0600, debugfs_dir, port,
&counters_fops);
}
}
/**
* tb_switch_debugfs_remove() - Remove all router debugfs entries
* @sw: Pointer to the router
*
* Removes all previously added debugfs entries under this router.
*/
void tb_switch_debugfs_remove(struct tb_switch *sw)
{
debugfs_remove_recursive(sw->debugfs_dir);
}
void tb_debugfs_init(void)
{
tb_debugfs_root = debugfs_create_dir("thunderbolt", NULL);
}
void tb_debugfs_exit(void)
{
debugfs_remove_recursive(tb_debugfs_root);
}