Merge tag 'driver-core-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg Kroah-Hartman:
 "Here are a number of firmware core fixes for 3.7, and some other minor
  fixes.  And some documentation updates thrown in for good measure.

  All have been in the linux-next tree for a while.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  Documentation:Chinese translation of Documentation/arm64/memory.txt
  Documentation:Chinese translation of Documentation/arm64/booting.txt
  Documentation:Chinese translation of Documentation/IRQ.txt
  firmware loader: document kernel direct loading
  sysfs: sysfs_pathname/sysfs_add_one: Use strlcat() instead of strcat()
  dynamic_debug: Remove unnecessary __used
  firmware loader: sync firmware cache by async_synchronize_full_domain
  firmware loader: let direct loading back on 'firmware_buf'
  firmware loader: fix one reqeust_firmware race
  firmware loader: cancel uncache work before caching firmware

1 files changed, 151 insertions, 115 deletions

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 81541452887b..8945f4e489ed 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -36,68 +36,6 @@ MODULE_AUTHOR("Manuel Estrada Sainz");
 MODULE_DESCRIPTION("Multi purpose firmware loading support");
 MODULE_LICENSE("GPL");
 
-static const char *fw_path[] = {
-        "/lib/firmware/updates/" UTS_RELEASE,
-        "/lib/firmware/updates",
-        "/lib/firmware/" UTS_RELEASE,
-        "/lib/firmware"
-};
-
-/* Don't inline this: 'struct kstat' is biggish */
-static noinline long fw_file_size(struct file *file)
-{
-        struct kstat st;
-        if (vfs_getattr(file->f_path.mnt, file->f_path.dentry, &st))
-                return -1;
-        if (!S_ISREG(st.mode))
-                return -1;
-        if (st.size != (long)st.size)
-                return -1;
-        return st.size;
-}
-
-static bool fw_read_file_contents(struct file *file, struct firmware *fw)
-{
-        long size;
-        char *buf;
-
-        size = fw_file_size(file);
-        if (size < 0)
-                return false;
-        buf = vmalloc(size);
-        if (!buf)
-                return false;
-        if (kernel_read(file, 0, buf, size) != size) {
-                vfree(buf);
-                return false;
-        }
-        fw->data = buf;
-        fw->size = size;
-        return true;
-}
-
-static bool fw_get_filesystem_firmware(struct firmware *fw, const char *name)
-{
-        int i;
-        bool success = false;
-        char *path = __getname();
-
-        for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
-                struct file *file;
-                snprintf(path, PATH_MAX, "%s/%s", fw_path[i], name);
-
-                file = filp_open(path, O_RDONLY, 0);
-                if (IS_ERR(file))
-                        continue;
-                success = fw_read_file_contents(file, fw);
-                fput(file);
-                if (success)
-                        break;
-        }
-        __putname(path);
-        return success;
-}
-
 /* Builtin firmware support */
 
 #ifdef CONFIG_FW_LOADER
@@ -150,6 +88,11 @@ enum {
         FW_STATUS_ABORT,
 };
 
+enum fw_buf_fmt {
+        VMALLOC_BUF,    /* used in direct loading */
+        PAGE_BUF,       /* used in loading via userspace */
+};
+
 static int loading_timeout = 60;        /* In seconds */
 
 static inline long firmware_loading_timeout(void)
@@ -173,8 +116,6 @@ struct firmware_cache {
         spinlock_t name_lock;
         struct list_head fw_names;
 
-        wait_queue_head_t wait_queue;
-        int cnt;
         struct delayed_work work;
 
         struct notifier_block   pm_notify;
@@ -187,6 +128,7 @@ struct firmware_buf {
         struct completion completion;
         struct firmware_cache *fwc;
         unsigned long status;
+        enum fw_buf_fmt fmt;
         void *data;
         size_t size;
         struct page **pages;
@@ -240,6 +182,7 @@ static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
         strcpy(buf->fw_id, fw_name);
         buf->fwc = fwc;
         init_completion(&buf->completion);
+        buf->fmt = VMALLOC_BUF;
 
         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 
@@ -307,10 +250,14 @@ static void __fw_free_buf(struct kref *ref)
         list_del(&buf->list);
         spin_unlock(&fwc->lock);
 
-        vunmap(buf->data);
-        for (i = 0; i < buf->nr_pages; i++)
-                __free_page(buf->pages[i]);
-        kfree(buf->pages);
+
+        if (buf->fmt == PAGE_BUF) {
+                vunmap(buf->data);
+                for (i = 0; i < buf->nr_pages; i++)
+                        __free_page(buf->pages[i]);
+                kfree(buf->pages);
+        } else
+                vfree(buf->data);
         kfree(buf);
 }
 
@@ -319,6 +266,69 @@ static void fw_free_buf(struct firmware_buf *buf)
         kref_put(&buf->ref, __fw_free_buf);
 }
 
+/* direct firmware loading support */
+static const char *fw_path[] = {
+        "/lib/firmware/updates/" UTS_RELEASE,
+        "/lib/firmware/updates",
+        "/lib/firmware/" UTS_RELEASE,
+        "/lib/firmware"
+};
+
+/* Don't inline this: 'struct kstat' is biggish */
+static noinline long fw_file_size(struct file *file)
+{
+        struct kstat st;
+        if (vfs_getattr(file->f_path.mnt, file->f_path.dentry, &st))
+                return -1;
+        if (!S_ISREG(st.mode))
+                return -1;
+        if (st.size != (long)st.size)
+                return -1;
+        return st.size;
+}
+
+static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
+{
+        long size;
+        char *buf;
+
+        size = fw_file_size(file);
+        if (size < 0)
+                return false;
+        buf = vmalloc(size);
+        if (!buf)
+                return false;
+        if (kernel_read(file, 0, buf, size) != size) {
+                vfree(buf);
+                return false;
+        }
+        fw_buf->data = buf;
+        fw_buf->size = size;
+        return true;
+}
+
+static bool fw_get_filesystem_firmware(struct firmware_buf *buf)
+{
+        int i;
+        bool success = false;
+        char *path = __getname();
+
+        for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
+                struct file *file;
+                snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
+
+                file = filp_open(path, O_RDONLY, 0);
+                if (IS_ERR(file))
+                        continue;
+                success = fw_read_file_contents(file, buf);
+                fput(file);
+                if (success)
+                        break;
+        }
+        __putname(path);
+        return success;
+}
+
 static struct firmware_priv *to_firmware_priv(struct device *dev)
 {
         return container_of(dev, struct firmware_priv, dev);
@@ -423,6 +433,21 @@ static void firmware_free_data(const struct firmware *fw)
 #ifndef PAGE_KERNEL_RO
 #define PAGE_KERNEL_RO PAGE_KERNEL
 #endif
+
+/* one pages buffer should be mapped/unmapped only once */
+static int fw_map_pages_buf(struct firmware_buf *buf)
+{
+        if (buf->fmt != PAGE_BUF)
+                return 0;
+
+        if (buf->data)
+                vunmap(buf->data);
+        buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
+        if (!buf->data)
+                return -ENOMEM;
+        return 0;
+}
+
 /**
  * firmware_loading_store - set value in the 'loading' control file
  * @dev: device pointer
@@ -467,6 +492,14 @@ static ssize_t firmware_loading_store(struct device *dev,
                 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);
+
+                        /*
+                         * Several loading requests may be pending on
+                         * one same firmware buf, so let all requests
+                         * see the mapped 'buf->data' once the loading
+                         * is completed.
+                         * */
+                        fw_map_pages_buf(fw_buf);
                         complete_all(&fw_buf->completion);
                         break;
                 }
@@ -670,15 +703,6 @@ exit:
         return fw_priv;
 }
 
-/* one pages buffer is mapped/unmapped only once */
-static int fw_map_pages_buf(struct firmware_buf *buf)
-{
-        buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
-        if (!buf->data)
-                return -ENOMEM;
-        return 0;
-}
-
 /* store the pages buffer info firmware from buf */
 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 {
@@ -778,11 +802,6 @@ _request_firmware_prepare(const struct firmware **firmware_p, const char *name,
                 return NULL;
         }
 
-        if (fw_get_filesystem_firmware(firmware, name)) {
-                dev_dbg(device, "firmware: direct-loading firmware %s\n", name);
-                return NULL;
-        }
-
         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
         if (!ret)
                 fw_priv = fw_create_instance(firmware, name, device,
@@ -832,6 +851,21 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
         struct device *f_dev = &fw_priv->dev;
         struct firmware_buf *buf = fw_priv->buf;
         struct firmware_cache *fwc = &fw_cache;
+        int direct_load = 0;
+
+        /* try direct loading from fs first */
+        if (fw_get_filesystem_firmware(buf)) {
+                dev_dbg(f_dev->parent, "firmware: direct-loading"
+                        " firmware %s\n", buf->fw_id);
+
+                set_bit(FW_STATUS_DONE, &buf->status);
+                complete_all(&buf->completion);
+                direct_load = 1;
+                goto handle_fw;
+        }
+
+        /* fall back on userspace loading */
+        buf->fmt = PAGE_BUF;
 
         dev_set_uevent_suppress(f_dev, true);
 
@@ -870,6 +904,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 
         del_timer_sync(&fw_priv->timeout);
 
+handle_fw:
         mutex_lock(&fw_lock);
         if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
                 retval = -ENOENT;
@@ -884,9 +919,6 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
         if (!retval && f_dev->parent)
                 fw_add_devm_name(f_dev->parent, buf->fw_id);
 
-        if (!retval)
-                retval = fw_map_pages_buf(buf);
-
         /*
          * After caching firmware image is started, let it piggyback
          * on request firmware.
@@ -902,6 +934,9 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
         fw_priv->buf = NULL;
         mutex_unlock(&fw_lock);
 
+        if (direct_load)
+                goto err_put_dev;
+
         device_remove_file(f_dev, &dev_attr_loading);
 err_del_bin_attr:
         device_remove_bin_file(f_dev, &firmware_attr_data);
@@ -1129,6 +1164,8 @@ int uncache_firmware(const char *fw_name)
 }
 
 #ifdef CONFIG_PM_SLEEP
+static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
+
 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
 {
         struct fw_cache_entry *fce;
@@ -1142,17 +1179,27 @@ exit:
         return fce;
 }
 
-static int fw_cache_piggyback_on_request(const char *name)
+static int __fw_entry_found(const char *name)
 {
         struct firmware_cache *fwc = &fw_cache;
         struct fw_cache_entry *fce;
-        int ret = 0;
 
-        spin_lock(&fwc->name_lock);
         list_for_each_entry(fce, &fwc->fw_names, list) {
                 if (!strcmp(fce->name, name))
-                        goto found;
+                        return 1;
         }
+        return 0;
+}
+
+static int fw_cache_piggyback_on_request(const char *name)
+{
+        struct firmware_cache *fwc = &fw_cache;
+        struct fw_cache_entry *fce;
+        int ret = 0;
+
+        spin_lock(&fwc->name_lock);
+        if (__fw_entry_found(name))
+                goto found;
 
         fce = alloc_fw_cache_entry(name);
         if (fce) {
@@ -1185,12 +1232,6 @@ static void __async_dev_cache_fw_image(void *fw_entry,
 
                 free_fw_cache_entry(fce);
         }
-
-        spin_lock(&fwc->name_lock);
-        fwc->cnt--;
-        spin_unlock(&fwc->name_lock);
-
-        wake_up(&fwc->wait_queue);
 }
 
 /* called with dev->devres_lock held */
@@ -1229,11 +1270,19 @@ static void dev_cache_fw_image(struct device *dev, void *data)
                 list_del(&fce->list);
 
                 spin_lock(&fwc->name_lock);
-                fwc->cnt++;
-                list_add(&fce->list, &fwc->fw_names);
+                /* only one cache entry for one firmware */
+                if (!__fw_entry_found(fce->name)) {
+                        list_add(&fce->list, &fwc->fw_names);
+                } else {
+                        free_fw_cache_entry(fce);
+                        fce = NULL;
+                }
                 spin_unlock(&fwc->name_lock);
 
-                async_schedule(__async_dev_cache_fw_image, (void *)fce);
+                if (fce)
+                        async_schedule_domain(__async_dev_cache_fw_image,
+                                              (void *)fce,
+                                              &fw_cache_domain);
         }
 }
 
@@ -1275,6 +1324,9 @@ static void device_cache_fw_images(void)
 
         pr_debug("%s\n", __func__);
 
+        /* cancel uncache work */
+        cancel_delayed_work_sync(&fwc->work);
+
         /*
          * use small loading timeout for caching devices' firmware
          * because all these firmware images have been loaded
@@ -1292,21 +1344,7 @@ static void device_cache_fw_images(void)
         mutex_unlock(&fw_lock);
 
         /* wait for completion of caching firmware for all devices */
-        spin_lock(&fwc->name_lock);
-        for (;;) {
-                prepare_to_wait(&fwc->wait_queue, &wait,
-                                TASK_UNINTERRUPTIBLE);
-                if (!fwc->cnt)
-                        break;
-
-                spin_unlock(&fwc->name_lock);
-
-                schedule();
-
-                spin_lock(&fwc->name_lock);
-        }
-        spin_unlock(&fwc->name_lock);
-        finish_wait(&fwc->wait_queue, &wait);
+        async_synchronize_full_domain(&fw_cache_domain);
 
         loading_timeout = old_timeout;
 }
@@ -1394,9 +1432,7 @@ static void __init fw_cache_init(void)
 #ifdef CONFIG_PM_SLEEP
         spin_lock_init(&fw_cache.name_lock);
         INIT_LIST_HEAD(&fw_cache.fw_names);
-        fw_cache.cnt = 0;
 
-        init_waitqueue_head(&fw_cache.wait_queue);
         INIT_DELAYED_WORK(&fw_cache.work,
                           device_uncache_fw_images_work);