From: Ahmad Masri <amasri@xxxxxxxxxxxxxx>
Accessing some of the memory of the device while the device is
resetting or suspending may cause unexpected error as the HW is still
not in a stable state. Prevent this access to guarantee successful
read/write memory operations.
Signed-off-by: Ahmad Masri <amasri@xxxxxxxxxxxxxx>
Signed-off-by: Maya Erez <merez@xxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/wil6210/debugfs.c | 26 +++++++++++---
drivers/net/wireless/ath/wil6210/main.c | 41 +++++++++++++++++------
drivers/net/wireless/ath/wil6210/pm.c | 27 +++++++++------
drivers/net/wireless/ath/wil6210/wil6210.h | 5 ++-
drivers/net/wireless/ath/wil6210/wil_crash_dump.c | 18 ++++------
5 files changed, 80 insertions(+), 37 deletions(-)
diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c
index e8f6d76..d1c3fe8 100644
--- a/drivers/net/wireless/ath/wil6210/debugfs.c
+++ b/drivers/net/wireless/ath/wil6210/debugfs.c
@@ -258,6 +258,11 @@ static void wil_print_mbox_ring(struct seq_file *s, const char *prefix,
wil_halp_vote(wil);
+ if (wil_mem_access_lock(wil)) {
+ wil_halp_unvote(wil);
+ return;
+ }
+
wil_memcpy_fromio_32(&r, off, sizeof(r));
wil_mbox_ring_le2cpus(&r);
/*
@@ -323,6 +328,7 @@ static void wil_print_mbox_ring(struct seq_file *s, const char *prefix,
}
out:
seq_puts(s, "}\n");
+ wil_mem_access_unlock(wil);
wil_halp_unvote(wil);
}
@@ -601,6 +607,12 @@ static int memread_show(struct seq_file *s, void *data)
if (ret < 0)
return ret;
+ ret = wil_mem_access_lock(wil);
+ if (ret) {
+ wil_pm_runtime_put(wil);
+ return ret;
+ }
+
a = wmi_buffer(wil, cpu_to_le32(mem_addr));
if (a)
@@ -608,6 +620,8 @@ static int memread_show(struct seq_file *s, void *data)
else
seq_printf(s, "[0x%08x] = INVALID\n", mem_addr);
+ wil_mem_access_unlock(wil);
+
wil_pm_runtime_put(wil);
return 0;
@@ -626,10 +640,6 @@ static ssize_t wil_read_file_ioblob(struct file *file, char __user *user_buf,
size_t unaligned_bytes, aligned_count, ret;
int rc;
- if (test_bit(wil_status_suspending, wil_blob->wil->status) ||
- test_bit(wil_status_suspended, wil_blob->wil->status))
- return 0;
-
if (pos < 0)
return -EINVAL;
@@ -656,11 +666,19 @@ static ssize_t wil_read_file_ioblob(struct file *file, char __user *user_buf,
return rc;
}
+ rc = wil_mem_access_lock(wil);
+ if (rc) {
+ kfree(buf);
+ wil_pm_runtime_put(wil);
+ return rc;
+ }
+
wil_memcpy_fromio_32(buf, (const void __iomem *)
wil_blob->blob.data + aligned_pos, aligned_count);
ret = copy_to_user(user_buf, buf + unaligned_bytes, count);
+ wil_mem_access_unlock(wil);
wil_pm_runtime_put(wil);
kfree(buf);
diff --git a/drivers/net/wireless/ath/wil6210/main.c b/drivers/net/wireless/ath/wil6210/main.c
index bd933a0..2563076 100644
--- a/drivers/net/wireless/ath/wil6210/main.c
+++ b/drivers/net/wireless/ath/wil6210/main.c
@@ -139,6 +139,28 @@ void wil_memcpy_toio_32(volatile void __iomem *dst, const void *src,
}
}
+/* Device memory access is prohibited while reset or suspend.
+ * wil_mem_access_lock protects accessing device memory in these cases
+ */
+int wil_mem_access_lock(struct wil6210_priv *wil)
+{
+ if (!down_read_trylock(&wil->mem_lock))
+ return -EBUSY;
+
+ if (test_bit(wil_status_suspending, wil->status) ||
+ test_bit(wil_status_suspended, wil->status)) {
+ up_read(&wil->mem_lock);
+ return -EBUSY;
+ }
+
+ return 0;
+}
+
+void wil_mem_access_unlock(struct wil6210_priv *wil)
+{
+ up_read(&wil->mem_lock);
+}
+
static void wil_ring_fini_tx(struct wil6210_priv *wil, int id)
{
struct wil_ring *ring = &wil->ring_tx[id];
@@ -678,6 +700,7 @@ int wil_priv_init(struct wil6210_priv *wil)
spin_lock_init(&wil->wmi_ev_lock);
spin_lock_init(&wil->net_queue_lock);
init_waitqueue_head(&wil->wq);
+ init_rwsem(&wil->mem_lock);
wil->wmi_wq = create_singlethread_workqueue(WIL_NAME "_wmi");
if (!wil->wmi_wq)
@@ -1577,15 +1600,6 @@ int wil_reset(struct wil6210_priv *wil, bool load_fw)
}
set_bit(wil_status_resetting, wil->status);
- if (test_bit(wil_status_collecting_dumps, wil->status)) {
- /* Device collects crash dump, cancel the reset.
- * following crash dump collection, reset would take place.
- */
- wil_dbg_misc(wil, "reject reset while collecting crash dump\n");
- rc = -EBUSY;
- goto out;
- }
-
mutex_lock(&wil->vif_mutex);
wil_abort_scan_all_vifs(wil, false);
mutex_unlock(&wil->vif_mutex);
@@ -1760,7 +1774,9 @@ int __wil_up(struct wil6210_priv *wil)
WARN_ON(!mutex_is_locked(&wil->mutex));
+ down_write(&wil->mem_lock);
rc = wil_reset(wil, true);
+ up_write(&wil->mem_lock);
if (rc)
return rc;
@@ -1834,6 +1850,7 @@ int wil_up(struct wil6210_priv *wil)
int __wil_down(struct wil6210_priv *wil)
{
+ int rc;
WARN_ON(!mutex_is_locked(&wil->mutex));
set_bit(wil_status_resetting, wil->status);
@@ -1853,7 +1870,11 @@ int __wil_down(struct wil6210_priv *wil)
wil_abort_scan_all_vifs(wil, false);
mutex_unlock(&wil->vif_mutex);
- return wil_reset(wil, false);
+ down_write(&wil->mem_lock);
+ rc = wil_reset(wil, false);
+ up_write(&wil->mem_lock);
+
+ return rc;
}
int wil_down(struct wil6210_priv *wil)
diff --git a/drivers/net/wireless/ath/wil6210/pm.c b/drivers/net/wireless/ath/wil6210/pm.c
index 9c59bc5..2f74ff9 100644
--- a/drivers/net/wireless/ath/wil6210/pm.c
+++ b/drivers/net/wireless/ath/wil6210/pm.c
@@ -195,14 +195,18 @@ static int wil_suspend_keep_radio_on(struct wil6210_priv *wil)
wil_dbg_pm(wil, "suspend keep radio on\n");
/* Prevent handling of new tx and wmi commands */
- set_bit(wil_status_suspending, wil->status);
- if (test_bit(wil_status_collecting_dumps, wil->status)) {
- /* Device collects crash dump, cancel the suspend */
- wil_dbg_pm(wil, "reject suspend while collecting crash dump\n");
- clear_bit(wil_status_suspending, wil->status);
+ rc = down_write_trylock(&wil->mem_lock);
+ if (!rc) {
+ wil_err(wil,
+ "device is busy. down_write_trylock failed, returned (0x%x)\n",
+ rc);
wil->suspend_stats.rejected_by_host++;
return -EBUSY;
}
+
+ set_bit(wil_status_suspending, wil->status);
+ up_write(&wil->mem_lock);
+
wil_pm_stop_all_net_queues(wil);
if (!wil_is_tx_idle(wil)) {
@@ -310,15 +314,18 @@ static int wil_suspend_radio_off(struct wil6210_priv *wil)
wil_dbg_pm(wil, "suspend radio off\n");
- set_bit(wil_status_suspending, wil->status);
- if (test_bit(wil_status_collecting_dumps, wil->status)) {
- /* Device collects crash dump, cancel the suspend */
- wil_dbg_pm(wil, "reject suspend while collecting crash dump\n");
- clear_bit(wil_status_suspending, wil->status);
+ rc = down_write_trylock(&wil->mem_lock);
+ if (!rc) {
+ wil_err(wil,
+ "device is busy. down_write_trylock failed, returned (0x%x)\n",
+ rc);
wil->suspend_stats.rejected_by_host++;
return -EBUSY;
}
+ set_bit(wil_status_suspending, wil->status);
+ up_write(&wil->mem_lock);
+
/* if netif up, hardware is alive, shut it down */
mutex_lock(&wil->vif_mutex);
active_ifaces = wil_has_active_ifaces(wil, true, false);
diff --git a/drivers/net/wireless/ath/wil6210/wil6210.h b/drivers/net/wireless/ath/wil6210/wil6210.h
index de97c4e..c7ab6c6 100644
--- a/drivers/net/wireless/ath/wil6210/wil6210.h
+++ b/drivers/net/wireless/ath/wil6210/wil6210.h
@@ -646,7 +646,6 @@ enum { /* for wil6210_priv.status */
wil_status_suspending, /* suspend in progress */
wil_status_suspended, /* suspend completed, device is suspended */
wil_status_resuming, /* resume in progress */
- wil_status_collecting_dumps, /* crashdump collection in progress */
wil_status_last /* keep last */
};
@@ -979,6 +978,8 @@ struct wil6210_priv {
struct wil_txrx_ops txrx_ops;
struct mutex mutex; /* for wil6210_priv access in wil_{up|down} */
+ /* for synchronizing device memory access while reset or suspend */
+ struct rw_semaphore mem_lock;
/* statistics */
atomic_t isr_count_rx, isr_count_tx;
/* debugfs */
@@ -1176,6 +1177,8 @@ void wil_memcpy_fromio_32(void *dst, const volatile void __iomem *src,
size_t count);
void wil_memcpy_toio_32(volatile void __iomem *dst, const void *src,
size_t count);
+int wil_mem_access_lock(struct wil6210_priv *wil);
+void wil_mem_access_unlock(struct wil6210_priv *wil);
struct wil6210_vif *
wil_vif_alloc(struct wil6210_priv *wil, const char *name,
diff --git a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
index dc33a0b..772cb00 100644
--- a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
+++ b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
@@ -1,6 +1,6 @@
/*
* Copyright (c) 2015,2017 Qualcomm Atheros, Inc.
- * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2019, The Linux Foundation. All rights reserved.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
@@ -57,7 +57,7 @@ static int wil_fw_get_crash_dump_bounds(struct wil6210_priv *wil,
int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
{
- int i;
+ int i, rc;
const struct fw_map *map;
void *data;
u32 host_min, dump_size, offset, len;
@@ -73,14 +73,9 @@ int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
return -EINVAL;
}
- set_bit(wil_status_collecting_dumps, wil->status);
- if (test_bit(wil_status_suspending, wil->status) ||
- test_bit(wil_status_suspended, wil->status) ||
- test_bit(wil_status_resetting, wil->status)) {
- wil_err(wil, "cannot collect fw dump during suspend/reset\n");
- clear_bit(wil_status_collecting_dumps, wil->status);
- return -EINVAL;
- }
+ rc = wil_mem_access_lock(wil);
+ if (rc)
+ return rc;
/* copy to crash dump area */
for (i = 0; i < ARRAY_SIZE(fw_mapping); i++) {
@@ -100,8 +95,7 @@ int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
wil_memcpy_fromio_32((void * __force)(dest + offset),
(const void __iomem * __force)data, len);
}
-
- clear_bit(wil_status_collecting_dumps, wil->status);
+ wil_mem_access_unlock(wil);
return 0;
}
--
1.9.1
