[PATCH iwl v4] ice: acquire NVM lock around each flash read
Robert Malz <[email protected]>
| Newsgroups | gmane.linux.kernel,gmane.linux.network |
|---|---|
| Message-ID | <[email protected]> |
FW caps the NVM read lock at a maximum of 3000ms regardless of the timeout
requested via ice_acquire_nvm(). ice_read_flat_nvm() splits a read into
multiple ice_aq_read_nvm() commands, one per 4KB sector, all issued under a
single lock taken by the caller. Reading a large region can exceed 3000ms,
so FW reclaims the lock mid-read and the remaining commands might fail.
Move the lock acquire/release into ice_read_flat_nvm() so it brackets each
individual ice_aq_read_nvm() command, ensuring the lock is never held
across more than one FW read.
ice_release_nvm() issues its own AQ command and overwrites
hw->adminq.sq_last_status, which some callers inspect after a failed read.
Add an optional read_aq_err output parameter to ice_read_flat_nvm() to
capture the failing read's AQ error before the release; callers that need
it (ice_discover_flash_size() and the ethtool/devlink log paths) use it
instead of sq_last_status, others pass NULL.
Callers that previously took the lock around ice_read_flat_nvm(),
ice_read_sr_word() or ice_read_flash_module() now call them without it.
The now-redundant per-block locking in ice_devlink_nvm_snapshot() is
dropped. ice_read_sr_word() is now a thin wrapper, so ice_read_sr_word_aq()
is folded into it.
Fixes: e94509906d6b ("ice: create function to read a section of the NVM and Shadow RAM")
Signed-off-by: Robert Malz <[email protected]>
---
v4:
- Fold ice_read_sr_word_aq() into ice_read_sr_word() now that the latter is
only a wrapper.
- Reduce the scope of read_aq_err in ice_devlink_nvm_snapshot() to the read
loop.
- Fix reverse christmas tree ordering of the added read_aq_err declarations.
v3:
- Log the failure via ice_debug() when ice_acquire_nvm() fails inside
ice_read_flat_nvm(), rather than silently aborting the read.
v2:
- Replace the save/restore of sq_last_status across ice_release_nvm(),
which could race with a concurrent AdminQ command, with a new optional
read_aq_err output parameter.
- Add missing "Return:" kdoc to ice_read_sr_word().
---
.../net/ethernet/intel/ice/devlink/devlink.c | 32 ++-----
drivers/net/ethernet/intel/ice/ice_ethtool.c | 16 +---
drivers/net/ethernet/intel/ice/ice_nvm.c | 90 ++++++++++---------
drivers/net/ethernet/intel/ice/ice_nvm.h | 2 +-
4 files changed, 58 insertions(+), 82 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/devlink/devlink.c b/drivers/net/ethernet/intel/ice/devlink/devlink.c
index 22b7d8e6bd9e..8c2b63eef82b 100644
--- a/drivers/net/ethernet/intel/ice/devlink/devlink.c
+++ b/drivers/net/ethernet/intel/ice/devlink/devlink.c
@@ -1890,27 +1890,18 @@ static int ice_devlink_nvm_snapshot(struct devlink *devlink,
*/
for (i = 0; i < num_blks; i++) {
u32 read_sz = min_t(u32, ICE_DEVLINK_READ_BLK_SIZE, left);
-
- status = ice_acquire_nvm(hw, ICE_RES_READ);
- if (status) {
- dev_dbg(dev, "ice_acquire_nvm failed, err %d aq_err %d\n",
- status, hw->adminq.sq_last_status);
- NL_SET_ERR_MSG_MOD(extack, "Failed to acquire NVM semaphore");
- vfree(nvm_data);
- return -EIO;
- }
+ enum libie_aq_err read_aq_err = LIBIE_AQ_RC_OK;
status = ice_read_flat_nvm(hw, i * ICE_DEVLINK_READ_BLK_SIZE,
- &read_sz, tmp, read_shadow_ram);
+ &read_sz, tmp, read_shadow_ram,
+ &read_aq_err);
if (status) {
dev_dbg(dev, "ice_read_flat_nvm failed after reading %u bytes, err %d aq_err %d\n",
- read_sz, status, hw->adminq.sq_last_status);
+ read_sz, status, read_aq_err);
NL_SET_ERR_MSG_MOD(extack, "Failed to read NVM contents");
- ice_release_nvm(hw);
vfree(nvm_data);
return -EIO;
}
- ice_release_nvm(hw);
tmp += read_sz;
left -= read_sz;
@@ -1943,6 +1934,7 @@ static int ice_devlink_nvm_read(struct devlink *devlink,
struct netlink_ext_ack *extack,
u64 offset, u32 size, u8 *data)
{
+ enum libie_aq_err read_aq_err = LIBIE_AQ_RC_OK;
struct ice_pf *pf = devlink_priv(devlink);
struct device *dev = ice_pf_to_dev(pf);
struct ice_hw *hw = &pf->hw;
@@ -1966,24 +1958,14 @@ static int ice_devlink_nvm_read(struct devlink *devlink,
return -ERANGE;
}
- status = ice_acquire_nvm(hw, ICE_RES_READ);
- if (status) {
- dev_dbg(dev, "ice_acquire_nvm failed, err %d aq_err %d\n",
- status, hw->adminq.sq_last_status);
- NL_SET_ERR_MSG_MOD(extack, "Failed to acquire NVM semaphore");
- return -EIO;
- }
-
status = ice_read_flat_nvm(hw, (u32)offset, &size, data,
- read_shadow_ram);
+ read_shadow_ram, &read_aq_err);
if (status) {
dev_dbg(dev, "ice_read_flat_nvm failed after reading %u bytes, err %d aq_err %d\n",
- size, status, hw->adminq.sq_last_status);
+ size, status, read_aq_err);
NL_SET_ERR_MSG_MOD(extack, "Failed to read NVM contents");
- ice_release_nvm(hw);
return -EIO;
}
- ice_release_nvm(hw);
return 0;
}
diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index 49371b065845..d3cc6fef6a09 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -853,6 +853,7 @@ static int
ice_get_eeprom(struct net_device *netdev, struct ethtool_eeprom *eeprom,
u8 *bytes)
{
+ enum libie_aq_err read_aq_err = LIBIE_AQ_RC_OK;
struct ice_pf *pf = ice_netdev_to_pf(netdev);
struct ice_hw *hw = &pf->hw;
struct device *dev;
@@ -869,24 +870,15 @@ ice_get_eeprom(struct net_device *netdev, struct ethtool_eeprom *eeprom,
if (!buf)
return -ENOMEM;
- ret = ice_acquire_nvm(hw, ICE_RES_READ);
- if (ret) {
- dev_err(dev, "ice_acquire_nvm failed, err %d aq_err %s\n",
- ret, libie_aq_str(hw->adminq.sq_last_status));
- goto out;
- }
-
ret = ice_read_flat_nvm(hw, eeprom->offset, &eeprom->len, buf,
- false);
+ false, &read_aq_err);
if (ret) {
dev_err(dev, "ice_read_flat_nvm failed, err %d aq_err %s\n",
- ret, libie_aq_str(hw->adminq.sq_last_status));
- goto release;
+ ret, libie_aq_str(read_aq_err));
+ goto out;
}
memcpy(bytes, buf, eeprom->len);
-release:
- ice_release_nvm(hw);
out:
kfree(buf);
return ret;
diff --git a/drivers/net/ethernet/intel/ice/ice_nvm.c b/drivers/net/ethernet/intel/ice/ice_nvm.c
index 7e187a804dfa..21f3b615dbbf 100644
--- a/drivers/net/ethernet/intel/ice/ice_nvm.c
+++ b/drivers/net/ethernet/intel/ice/ice_nvm.c
@@ -53,17 +53,27 @@ int ice_aq_read_nvm(struct ice_hw *hw, u16 module_typeid, u32 offset,
* @length: (in) number of bytes to read; (out) number of bytes actually read
* @data: buffer to return data in (sized to fit the specified length)
* @read_shadow_ram: if true, read from shadow RAM instead of NVM
+ * @read_aq_err: if non-NULL, receives the AQ error status of the failing read
*
* Reads a portion of the NVM, as a flat memory space. This function correctly
* breaks read requests across Shadow RAM sectors and ensures that no single
* read request exceeds the maximum 4KB read for a single AdminQ command.
*
+ * FW caps the read lock at a maximum of 3000ms, so a read spanning multiple
+ * 4KB sectors cannot be done under a single lock without FW reclaiming it
+ * mid-read. The NVM lock is therefore acquired and released around each AQ
+ * read, so this function must be called without the lock held.
+ *
+ * Since ice_release_nvm() issues an AQ command that overwrites
+ * hw->adminq.sq_last_status, callers that need the failing read's AQ error
+ * must use @read_aq_err rather than inspecting sq_last_status afterwards.
+ *
* Returns a status code on failure. Note that the data pointer may be
* partially updated if some reads succeed before a failure.
*/
int
ice_read_flat_nvm(struct ice_hw *hw, u32 offset, u32 *length, u8 *data,
- bool read_shadow_ram)
+ bool read_shadow_ram, enum libie_aq_err *read_aq_err)
{
u32 inlen = *length;
u32 bytes_read = 0;
@@ -92,12 +102,30 @@ ice_read_flat_nvm(struct ice_hw *hw, u32 offset, u32 *length, u8 *data,
last_cmd = !(bytes_read + read_size < inlen);
+ status = ice_acquire_nvm(hw, ICE_RES_READ);
+ if (status) {
+ ice_debug(hw, ICE_DBG_NVM, "Failed to acquire NVM lock, err %d aq_err %s\n",
+ status, libie_aq_str(hw->adminq.sq_last_status));
+ break;
+ }
+
status = ice_aq_read_nvm(hw, ICE_AQC_NVM_START_POINT,
offset, read_size,
data + bytes_read, last_cmd,
read_shadow_ram, NULL);
- if (status)
+ if (status) {
+ /* Capture the read's AQ error before ice_release_nvm()
+ * issues its own AQ command and overwrites
+ * sq_last_status.
+ */
+ if (read_aq_err)
+ *read_aq_err = hw->adminq.sq_last_status;
+
+ ice_release_nvm(hw);
break;
+ }
+
+ ice_release_nvm(hw);
bytes_read += read_size;
offset += read_size;
@@ -177,14 +205,19 @@ int ice_aq_erase_nvm(struct ice_hw *hw, u16 module_typeid, struct ice_sq_cd *cd)
}
/**
- * ice_read_sr_word_aq - Reads Shadow RAM via AQ
+ * ice_read_sr_word - Reads Shadow RAM word
* @hw: pointer to the HW structure
* @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF)
* @data: word read from the Shadow RAM
*
* Reads one 16 bit word from the Shadow RAM using ice_read_flat_nvm.
+ *
+ * The NVM lock is acquired and released internally by ice_read_flat_nvm()
+ * around the FW read, so this function must be called without the lock held.
+ *
+ * Return: zero on success, or a negative error code on failure.
*/
-static int ice_read_sr_word_aq(struct ice_hw *hw, u16 offset, u16 *data)
+int ice_read_sr_word(struct ice_hw *hw, u16 offset, u16 *data)
{
u32 bytes = sizeof(u16);
__le16 data_local;
@@ -194,7 +227,7 @@ static int ice_read_sr_word_aq(struct ice_hw *hw, u16 offset, u16 *data)
* Shadow RAM sector restrictions necessary when reading from the NVM.
*/
status = ice_read_flat_nvm(hw, offset * sizeof(u16), &bytes,
- (__force u8 *)&data_local, true);
+ (__force u8 *)&data_local, true, NULL);
if (status)
return status;
@@ -330,13 +363,8 @@ ice_read_flash_module(struct ice_hw *hw, enum ice_bank_select bank, u16 module,
return -EINVAL;
}
- status = ice_acquire_nvm(hw, ICE_RES_READ);
- if (status)
- return status;
-
- status = ice_read_flat_nvm(hw, start + offset, &length, data, false);
-
- ice_release_nvm(hw);
+ status = ice_read_flat_nvm(hw, start + offset, &length, data, false,
+ NULL);
return status;
}
@@ -418,27 +446,6 @@ ice_read_netlist_module(struct ice_hw *hw, enum ice_bank_select bank, u32 offset
return status;
}
-/**
- * ice_read_sr_word - Reads Shadow RAM word and acquire NVM if necessary
- * @hw: pointer to the HW structure
- * @offset: offset of the Shadow RAM word to read (0x000000 - 0x001FFF)
- * @data: word read from the Shadow RAM
- *
- * Reads one 16 bit word from the Shadow RAM using the ice_read_sr_word_aq.
- */
-int ice_read_sr_word(struct ice_hw *hw, u16 offset, u16 *data)
-{
- int status;
-
- status = ice_acquire_nvm(hw, ICE_RES_READ);
- if (!status) {
- status = ice_read_sr_word_aq(hw, offset, data);
- ice_release_nvm(hw);
- }
-
- return status;
-}
-
/**
* ice_get_pfa_module_tlv - Reads sub module TLV from NVM PFA
* @hw: pointer to hardware structure
@@ -856,20 +863,18 @@ int ice_get_inactive_netlist_ver(struct ice_hw *hw, struct ice_netlist_info *net
static int ice_discover_flash_size(struct ice_hw *hw)
{
u32 min_size = 0, max_size = ICE_AQC_NVM_MAX_OFFSET + 1;
- int status;
-
- status = ice_acquire_nvm(hw, ICE_RES_READ);
- if (status)
- return status;
+ int status = 0;
while ((max_size - min_size) > 1) {
+ enum libie_aq_err read_aq_err = LIBIE_AQ_RC_OK;
u32 offset = (max_size + min_size) / 2;
u32 len = 1;
u8 data;
- status = ice_read_flat_nvm(hw, offset, &len, &data, false);
+ status = ice_read_flat_nvm(hw, offset, &len, &data, false,
+ &read_aq_err);
if (status == -EIO &&
- hw->adminq.sq_last_status == LIBIE_AQ_RC_EINVAL) {
+ read_aq_err == LIBIE_AQ_RC_EINVAL) {
ice_debug(hw, ICE_DBG_NVM, "%s: New upper bound of %u bytes\n",
__func__, offset);
status = 0;
@@ -880,7 +885,7 @@ static int ice_discover_flash_size(struct ice_hw *hw)
min_size = offset;
} else {
/* an unexpected error occurred */
- goto err_read_flat_nvm;
+ return status;
}
}
@@ -888,9 +893,6 @@ static int ice_discover_flash_size(struct ice_hw *hw)
hw->flash.flash_size = max_size;
-err_read_flat_nvm:
- ice_release_nvm(hw);
-
return status;
}
diff --git a/drivers/net/ethernet/intel/ice/ice_nvm.h b/drivers/net/ethernet/intel/ice/ice_nvm.h
index 63cdc6bdac58..e1d1a11f5ca4 100644
--- a/drivers/net/ethernet/intel/ice/ice_nvm.h
+++ b/drivers/net/ethernet/intel/ice/ice_nvm.h
@@ -19,7 +19,7 @@ int ice_aq_read_nvm(struct ice_hw *hw, u16 module_typeid, u32 offset,
bool read_shadow_ram, struct ice_sq_cd *cd);
int
ice_read_flat_nvm(struct ice_hw *hw, u32 offset, u32 *length, u8 *data,
- bool read_shadow_ram);
+ bool read_shadow_ram, enum libie_aq_err *read_aq_err);
int
ice_get_pfa_module_tlv(struct ice_hw *hw, u16 *module_tlv, u16 *module_tlv_len,
u16 module_type);
--
2.34.1