linux-kernel - [PATCH v4 2/8] firmware_loader: Check fw_state_is_done in loading

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Message-Id: <20220419231658.664388-3-russell.h.weight@intel.com>
Date:   Tue, 19 Apr 2022 16:16:52 -0700
From:   Russ Weight <russell.h.weight@...el.com>
To:     mcgrof@...nel.org, rafael@...nel.org, linux-kernel@...r.kernel.org
Cc:     trix@...hat.com, lgoncalv@...hat.com, yilun.xu@...el.com,
        hao.wu@...el.com, matthew.gerlach@...ux.intel.com,
        basheer.ahmed.muddebihal@...el.com, tianfei.zhang@...el.com,
        Russ Weight <russell.h.weight@...el.com>
Subject: [PATCH v4 2/8] firmware_loader: Check fw_state_is_done in loading_store

Rename fw_sysfs_done() and fw_sysfs_loading() to fw_state_is_done() and
fw_state_is_loading() respectively, and place them along side companion
functions in drivers/base/firmware_loader/firmware.h.

Use the fw_state_is_done() function to exit early from
firmware_loading_store() if the state is already "done". This is being done
in preparation for supporting persistent sysfs nodes to allow userspace to
upload firmware to a device, potentially reusing the sysfs loading and data
files multiple times.

Reviewed-by: Luis Chamberlain <mcgrof@...nel.org>
Reviewed-by: Tianfei zhang <tianfei.zhang@...el.com>
Signed-off-by: Russ Weight <russell.h.weight@...el.com>
---
v1:
  - No change from RFC patch
v2:
  - It was discovered that the new function in v1, fw_state_is_done(), is
    equivalent to the existing fw_sysfs_done() function. Renamed
    fw_sysfs_done() and fw_sysfs_loading() to fw_state_is_done() and
    fw_state_is_loading() respectively, and placed them along side companion
    functions in drivers/base/firmware_loader/firmware.h.
  - Removed the "if !fw_sysfs_done(fw_priv))" condition in switch case 1 of
    firmware_loading_store(). It is rendered unnecessary by other changes
    to the function by this patch.
v3:
  - Added Reviewed-by tag
v4:
  - Added Reviewed-by tag
---
 drivers/base/firmware_loader/fallback.c | 28 +++++++------------------
 drivers/base/firmware_loader/firmware.h | 10 +++++++++
 2 files changed, 18 insertions(+), 20 deletions(-)

diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index 4afb0e9312c0..8063eb595719 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -58,16 +58,6 @@ static long firmware_loading_timeout(void)
 		__firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET;
 }
 
-static inline bool fw_sysfs_done(struct fw_priv *fw_priv)
-{
-	return __fw_state_check(fw_priv, FW_STATUS_DONE);
-}
-
-static inline bool fw_sysfs_loading(struct fw_priv *fw_priv)
-{
-	return __fw_state_check(fw_priv, FW_STATUS_LOADING);
-}
-
 static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv,  long timeout)
 {
 	return __fw_state_wait_common(fw_priv, timeout);
@@ -91,7 +81,7 @@ static void __fw_load_abort(struct fw_priv *fw_priv)
 	 * There is a small window in which user can write to 'loading'
 	 * between loading done/aborted and disappearance of 'loading'
 	 */
-	if (fw_state_is_aborted(fw_priv) || fw_sysfs_done(fw_priv))
+	if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv))
 		return;
 
 	fw_state_aborted(fw_priv);
@@ -220,7 +210,7 @@ static ssize_t firmware_loading_show(struct device *dev,
 
 	mutex_lock(&fw_lock);
 	if (fw_sysfs->fw_priv)
-		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
+		loading = fw_state_is_loading(fw_sysfs->fw_priv);
 	mutex_unlock(&fw_lock);
 
 	return sysfs_emit(buf, "%d\n", loading);
@@ -250,19 +240,17 @@ static ssize_t firmware_loading_store(struct device *dev,
 
 	mutex_lock(&fw_lock);
 	fw_priv = fw_sysfs->fw_priv;
-	if (fw_state_is_aborted(fw_priv))
+	if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv))
 		goto out;
 
 	switch (loading) {
 	case 1:
 		/* discarding any previous partial load */
-		if (!fw_sysfs_done(fw_priv)) {
-			fw_free_paged_buf(fw_priv);
-			fw_state_start(fw_priv);
-		}
+		fw_free_paged_buf(fw_priv);
+		fw_state_start(fw_priv);
 		break;
 	case 0:
-		if (fw_sysfs_loading(fw_priv)) {
+		if (fw_state_is_loading(fw_priv)) {
 			int rc;
 
 			/*
@@ -350,7 +338,7 @@ static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 
 	mutex_lock(&fw_lock);
 	fw_priv = fw_sysfs->fw_priv;
-	if (!fw_priv || fw_sysfs_done(fw_priv)) {
+	if (!fw_priv || fw_state_is_done(fw_priv)) {
 		ret_count = -ENODEV;
 		goto out;
 	}
@@ -410,7 +398,7 @@ static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 
 	mutex_lock(&fw_lock);
 	fw_priv = fw_sysfs->fw_priv;
-	if (!fw_priv || fw_sysfs_done(fw_priv)) {
+	if (!fw_priv || fw_state_is_done(fw_priv)) {
 		retval = -ENODEV;
 		goto out;
 	}
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
index 2889f446ad41..d5ff32a1ba2d 100644
--- a/drivers/base/firmware_loader/firmware.h
+++ b/drivers/base/firmware_loader/firmware.h
@@ -149,6 +149,16 @@ static inline void fw_state_done(struct fw_priv *fw_priv)
 	__fw_state_set(fw_priv, FW_STATUS_DONE);
 }
 
+static inline bool fw_state_is_done(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_DONE);
+}
+
+static inline bool fw_state_is_loading(struct fw_priv *fw_priv)
+{
+	return __fw_state_check(fw_priv, FW_STATUS_LOADING);
+}
+
 int assign_fw(struct firmware *fw, struct device *device);
 
 #ifdef CONFIG_FW_LOADER
-- 
2.25.1