firmware loader: introduce firmware_buf

This patch introduces struct firmware_buf to describe the buffer
which holds the firmware data, which will make the following
cache_firmware/uncache_firmware implemented easily.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 102 insertions, 78 deletions

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 04c75b56f4fc..5f2076e5d5b1 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -89,7 +89,7 @@ static inline long firmware_loading_timeout(void)
  * guarding for corner cases a global lock should be OK */
 static DEFINE_MUTEX(fw_lock);
 
-struct firmware_priv {
+struct firmware_buf {
         struct completion completion;
         struct firmware *fw;
         unsigned long status;
@@ -98,10 +98,14 @@ struct firmware_priv {
         struct page **pages;
         int nr_pages;
         int page_array_size;
+        char fw_id[];
+};
+
+struct firmware_priv {
         struct timer_list timeout;
-        struct device dev;
         bool nowait;
-        char fw_id[];
+        struct device dev;
+        struct firmware_buf *buf;
 };
 
 static struct firmware_priv *to_firmware_priv(struct device *dev)
@@ -111,8 +115,10 @@ static struct firmware_priv *to_firmware_priv(struct device *dev)
 
 static void fw_load_abort(struct firmware_priv *fw_priv)
 {
-        set_bit(FW_STATUS_ABORT, &fw_priv->status);
-        complete(&fw_priv->completion);
+        struct firmware_buf *buf = fw_priv->buf;
+
+        set_bit(FW_STATUS_ABORT, &buf->status);
+        complete(&buf->completion);
 }
 
 static ssize_t firmware_timeout_show(struct class *class,
@@ -152,15 +158,21 @@ static struct class_attribute firmware_class_attrs[] = {
         __ATTR_NULL
 };
 
-static void fw_dev_release(struct device *dev)
+static void fw_free_buf(struct firmware_buf *buf)
 {
-        struct firmware_priv *fw_priv = to_firmware_priv(dev);
         int i;
 
-        /* free untransfered pages buffer */
-        for (i = 0; i < fw_priv->nr_pages; i++)
-                __free_page(fw_priv->pages[i]);
-        kfree(fw_priv->pages);
+        if (!buf)
+                return;
+
+        for (i = 0; i < buf->nr_pages; i++)
+                __free_page(buf->pages[i]);
+        kfree(buf->pages);
+}
+
+static void fw_dev_release(struct device *dev)
+{
+        struct firmware_priv *fw_priv = to_firmware_priv(dev);
 
         kfree(fw_priv);
 
@@ -171,7 +183,7 @@ static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 
-        if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->fw_id))
+        if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
                 return -ENOMEM;
         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
                 return -ENOMEM;
@@ -192,7 +204,7 @@ static ssize_t firmware_loading_show(struct device *dev,
                                      struct device_attribute *attr, char *buf)
 {
         struct firmware_priv *fw_priv = to_firmware_priv(dev);
-        int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status);
+        int loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 
         return sprintf(buf, "%d\n", loading);
 }
@@ -231,32 +243,33 @@ static ssize_t firmware_loading_store(struct device *dev,
                                       const char *buf, size_t count)
 {
         struct firmware_priv *fw_priv = to_firmware_priv(dev);
+        struct firmware_buf *fw_buf = fw_priv->buf;
         int loading = simple_strtol(buf, NULL, 10);
         int i;
 
         mutex_lock(&fw_lock);
 
-        if (!fw_priv->fw)
+        if (!fw_buf)
                 goto out;
 
         switch (loading) {
         case 1:
                 /* discarding any previous partial load */
-                if (!test_bit(FW_STATUS_DONE, &fw_priv->status)) {
-                        for (i = 0; i < fw_priv->nr_pages; i++)
-                                __free_page(fw_priv->pages[i]);
-                        kfree(fw_priv->pages);
-                        fw_priv->pages = NULL;
-                        fw_priv->page_array_size = 0;
-                        fw_priv->nr_pages = 0;
-                        set_bit(FW_STATUS_LOADING, &fw_priv->status);
+                if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
+                        for (i = 0; i < fw_buf->nr_pages; i++)
+                                __free_page(fw_buf->pages[i]);
+                        kfree(fw_buf->pages);
+                        fw_buf->pages = NULL;
+                        fw_buf->page_array_size = 0;
+                        fw_buf->nr_pages = 0;
+                        set_bit(FW_STATUS_LOADING, &fw_buf->status);
                 }
                 break;
         case 0:
-                if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) {
-                        set_bit(FW_STATUS_DONE, &fw_priv->status);
-                        clear_bit(FW_STATUS_LOADING, &fw_priv->status);
-                        complete(&fw_priv->completion);
+                if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
+                        set_bit(FW_STATUS_DONE, &fw_buf->status);
+                        clear_bit(FW_STATUS_LOADING, &fw_buf->status);
+                        complete(&fw_buf->completion);
                         break;
                 }
                 /* fallthrough */
@@ -280,21 +293,21 @@ static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 {
         struct device *dev = kobj_to_dev(kobj);
         struct firmware_priv *fw_priv = to_firmware_priv(dev);
-        struct firmware *fw;
+        struct firmware_buf *buf;
         ssize_t ret_count;
 
         mutex_lock(&fw_lock);
-        fw = fw_priv->fw;
-        if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
+        buf = fw_priv->buf;
+        if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
                 ret_count = -ENODEV;
                 goto out;
         }
-        if (offset > fw_priv->size) {
+        if (offset > buf->size) {
                 ret_count = 0;
                 goto out;
         }
-        if (count > fw_priv->size - offset)
-                count = fw_priv->size - offset;
+        if (count > buf->size - offset)
+                count = buf->size - offset;
 
         ret_count = count;
 
@@ -304,11 +317,11 @@ static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
                 int page_ofs = offset & (PAGE_SIZE-1);
                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 
-                page_data = kmap(fw_priv->pages[page_nr]);
+                page_data = kmap(buf->pages[page_nr]);
 
                 memcpy(buffer, page_data + page_ofs, page_cnt);
 
-                kunmap(fw_priv->pages[page_nr]);
+                kunmap(buf->pages[page_nr]);
                 buffer += page_cnt;
                 offset += page_cnt;
                 count -= page_cnt;
@@ -320,12 +333,13 @@ out:
 
 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 {
+        struct firmware_buf *buf = fw_priv->buf;
         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 
         /* If the array of pages is too small, grow it... */
-        if (fw_priv->page_array_size < pages_needed) {
+        if (buf->page_array_size < pages_needed) {
                 int new_array_size = max(pages_needed,
-                                         fw_priv->page_array_size * 2);
+                                         buf->page_array_size * 2);
                 struct page **new_pages;
 
                 new_pages = kmalloc(new_array_size * sizeof(void *),
@@ -334,24 +348,24 @@ static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
                         fw_load_abort(fw_priv);
                         return -ENOMEM;
                 }
-                memcpy(new_pages, fw_priv->pages,
-                       fw_priv->page_array_size * sizeof(void *));
-                memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
-                       (new_array_size - fw_priv->page_array_size));
-                kfree(fw_priv->pages);
-                fw_priv->pages = new_pages;
-                fw_priv->page_array_size = new_array_size;
+                memcpy(new_pages, buf->pages,
+                       buf->page_array_size * sizeof(void *));
+                memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
+                       (new_array_size - buf->page_array_size));
+                kfree(buf->pages);
+                buf->pages = new_pages;
+                buf->page_array_size = new_array_size;
         }
 
-        while (fw_priv->nr_pages < pages_needed) {
-                fw_priv->pages[fw_priv->nr_pages] =
+        while (buf->nr_pages < pages_needed) {
+                buf->pages[buf->nr_pages] =
                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 
-                if (!fw_priv->pages[fw_priv->nr_pages]) {
+                if (!buf->pages[buf->nr_pages]) {
                         fw_load_abort(fw_priv);
                         return -ENOMEM;
                 }
-                fw_priv->nr_pages++;
+                buf->nr_pages++;
         }
         return 0;
 }
@@ -374,15 +388,15 @@ static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 {
         struct device *dev = kobj_to_dev(kobj);
         struct firmware_priv *fw_priv = to_firmware_priv(dev);
-        struct firmware *fw;
+        struct firmware_buf *buf;
         ssize_t retval;
 
         if (!capable(CAP_SYS_RAWIO))
                 return -EPERM;
 
         mutex_lock(&fw_lock);
-        fw = fw_priv->fw;
-        if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
+        buf = fw_priv->buf;
+        if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
                 retval = -ENODEV;
                 goto out;
         }
@@ -399,17 +413,17 @@ static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
                 int page_ofs = offset & (PAGE_SIZE - 1);
                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 
-                page_data = kmap(fw_priv->pages[page_nr]);
+                page_data = kmap(buf->pages[page_nr]);
 
                 memcpy(page_data + page_ofs, buffer, page_cnt);
 
-                kunmap(fw_priv->pages[page_nr]);
+                kunmap(buf->pages[page_nr]);
                 buffer += page_cnt;
                 offset += page_cnt;
                 count -= page_cnt;
         }
 
-        fw_priv->size = max_t(size_t, offset, fw_priv->size);
+        buf->size = max_t(size_t, offset, buf->size);
 out:
         mutex_unlock(&fw_lock);
         return retval;
@@ -434,20 +448,31 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
                    struct device *device, bool uevent, bool nowait)
 {
         struct firmware_priv *fw_priv;
+        struct firmware_buf *buf;
         struct device *f_dev;
 
-        fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
+        fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
         if (!fw_priv) {
                 dev_err(device, "%s: kmalloc failed\n", __func__);
-                return ERR_PTR(-ENOMEM);
+                fw_priv = ERR_PTR(-ENOMEM);
+                goto exit;
+        }
+
+        buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1, GFP_KERNEL);
+        if (!buf) {
+                dev_err(device, "%s: kmalloc failed\n", __func__);
+                kfree(fw_priv);
+                fw_priv = ERR_PTR(-ENOMEM);
+                goto exit;
         }
 
-        fw_priv->fw = firmware;
+        buf->fw = firmware;
+        fw_priv->buf = buf;
         fw_priv->nowait = nowait;
-        strcpy(fw_priv->fw_id, fw_name);
-        init_completion(&fw_priv->completion);
         setup_timer(&fw_priv->timeout,
                     firmware_class_timeout, (u_long) fw_priv);
+        strcpy(buf->fw_id, fw_name);
+        init_completion(&buf->completion);
 
         f_dev = &fw_priv->dev;
 
@@ -455,7 +480,7 @@ fw_create_instance(struct firmware *firmware, const char *fw_name,
         dev_set_name(f_dev, "%s", fw_name);
         f_dev->parent = device;
         f_dev->class = &firmware_class;
-
+exit:
         return fw_priv;
 }
 
@@ -496,24 +521,18 @@ static void _request_firmware_cleanup(const struct firmware **firmware_p)
 }
 
 /* transfer the ownership of pages to firmware */
-static int fw_set_page_data(struct firmware_priv *fw_priv)
+static int fw_set_page_data(struct firmware_buf *buf)
 {
-        struct firmware *fw = fw_priv->fw;
+        struct firmware *fw = buf->fw;
 
-        fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages,
-                                0, PAGE_KERNEL_RO);
-        if (!fw_priv->data)
+        buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
+        if (!buf->data)
                 return -ENOMEM;
 
-        fw->data = fw_priv->data;
-        fw->pages = fw_priv->pages;
-        fw->size = fw_priv->size;
-
-        WARN_ON(PFN_UP(fw->size) != fw_priv->nr_pages);
-
-        fw_priv->nr_pages = 0;
-        fw_priv->pages = NULL;
-        fw_priv->data = NULL;
+        fw->data = buf->data;
+        fw->pages = buf->pages;
+        fw->size = buf->size;
+        WARN_ON(PFN_UP(fw->size) != buf->nr_pages);
 
         return 0;
 }
@@ -523,6 +542,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 {
         int retval = 0;
         struct device *f_dev = &fw_priv->dev;
+        struct firmware_buf *buf = fw_priv->buf;
 
         dev_set_uevent_suppress(f_dev, true);
 
@@ -549,7 +569,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 
         if (uevent) {
                 dev_set_uevent_suppress(f_dev, false);
-                dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_id);
+                dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
                 if (timeout != MAX_SCHEDULE_TIMEOUT)
                         mod_timer(&fw_priv->timeout,
                                   round_jiffies_up(jiffies + timeout));
@@ -557,18 +577,22 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
         }
 
-        wait_for_completion(&fw_priv->completion);
+        wait_for_completion(&buf->completion);
 
         del_timer_sync(&fw_priv->timeout);
 
         mutex_lock(&fw_lock);
-        if (!fw_priv->size || test_bit(FW_STATUS_ABORT, &fw_priv->status))
+        if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
                 retval = -ENOENT;
 
         /* transfer pages ownership at the last minute */
         if (!retval)
-                retval = fw_set_page_data(fw_priv);
-        fw_priv->fw = NULL;
+                retval = fw_set_page_data(buf);
+        if (retval)
+                fw_free_buf(buf); /* free untransfered pages buffer */
+
+        kfree(buf);
+        fw_priv->buf = NULL;
         mutex_unlock(&fw_lock);
 
         device_remove_file(f_dev, &dev_attr_loading);