LCOV - code coverage report
Current view: top level - drivers/base/firmware_loader - main.c (source / functions) Hit Total Coverage
Test: coverage.info Lines: 23 419 5.5 %
Date: 2023-07-19 18:55:55 Functions: 4 44 9.1 %

          Line data    Source code
       1             : // SPDX-License-Identifier: GPL-2.0
       2             : /*
       3             :  * main.c - Multi purpose firmware loading support
       4             :  *
       5             :  * Copyright (c) 2003 Manuel Estrada Sainz
       6             :  *
       7             :  * Please see Documentation/driver-api/firmware/ for more information.
       8             :  *
       9             :  */
      10             : 
      11             : #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
      12             : 
      13             : #include <linux/capability.h>
      14             : #include <linux/device.h>
      15             : #include <linux/kernel_read_file.h>
      16             : #include <linux/module.h>
      17             : #include <linux/init.h>
      18             : #include <linux/initrd.h>
      19             : #include <linux/timer.h>
      20             : #include <linux/vmalloc.h>
      21             : #include <linux/interrupt.h>
      22             : #include <linux/bitops.h>
      23             : #include <linux/mutex.h>
      24             : #include <linux/workqueue.h>
      25             : #include <linux/highmem.h>
      26             : #include <linux/firmware.h>
      27             : #include <linux/slab.h>
      28             : #include <linux/sched.h>
      29             : #include <linux/file.h>
      30             : #include <linux/list.h>
      31             : #include <linux/fs.h>
      32             : #include <linux/async.h>
      33             : #include <linux/pm.h>
      34             : #include <linux/suspend.h>
      35             : #include <linux/syscore_ops.h>
      36             : #include <linux/reboot.h>
      37             : #include <linux/security.h>
      38             : #include <linux/zstd.h>
      39             : #include <linux/xz.h>
      40             : 
      41             : #include <generated/utsrelease.h>
      42             : 
      43             : #include "../base.h"
      44             : #include "firmware.h"
      45             : #include "fallback.h"
      46             : 
      47             : MODULE_AUTHOR("Manuel Estrada Sainz");
      48             : MODULE_DESCRIPTION("Multi purpose firmware loading support");
      49             : MODULE_LICENSE("GPL");
      50             : 
      51             : struct firmware_cache {
      52             :         /* firmware_buf instance will be added into the below list */
      53             :         spinlock_t lock;
      54             :         struct list_head head;
      55             :         int state;
      56             : 
      57             : #ifdef CONFIG_FW_CACHE
      58             :         /*
      59             :          * Names of firmware images which have been cached successfully
      60             :          * will be added into the below list so that device uncache
      61             :          * helper can trace which firmware images have been cached
      62             :          * before.
      63             :          */
      64             :         spinlock_t name_lock;
      65             :         struct list_head fw_names;
      66             : 
      67             :         struct delayed_work work;
      68             : 
      69             :         struct notifier_block   pm_notify;
      70             : #endif
      71             : };
      72             : 
      73             : struct fw_cache_entry {
      74             :         struct list_head list;
      75             :         const char *name;
      76             : };
      77             : 
      78             : struct fw_name_devm {
      79             :         unsigned long magic;
      80             :         const char *name;
      81             : };
      82             : 
      83             : static inline struct fw_priv *to_fw_priv(struct kref *ref)
      84             : {
      85           0 :         return container_of(ref, struct fw_priv, ref);
      86             : }
      87             : 
      88             : #define FW_LOADER_NO_CACHE      0
      89             : #define FW_LOADER_START_CACHE   1
      90             : 
      91             : /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
      92             :  * guarding for corner cases a global lock should be OK */
      93             : DEFINE_MUTEX(fw_lock);
      94             : 
      95             : struct firmware_cache fw_cache;
      96             : 
      97           0 : void fw_state_init(struct fw_priv *fw_priv)
      98             : {
      99           0 :         struct fw_state *fw_st = &fw_priv->fw_st;
     100             : 
     101           0 :         init_completion(&fw_st->completion);
     102           0 :         fw_st->status = FW_STATUS_UNKNOWN;
     103           0 : }
     104             : 
     105             : static inline int fw_state_wait(struct fw_priv *fw_priv)
     106             : {
     107           0 :         return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
     108             : }
     109             : 
     110             : static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
     111             : 
     112           0 : static struct fw_priv *__allocate_fw_priv(const char *fw_name,
     113             :                                           struct firmware_cache *fwc,
     114             :                                           void *dbuf,
     115             :                                           size_t size,
     116             :                                           size_t offset,
     117             :                                           u32 opt_flags)
     118             : {
     119             :         struct fw_priv *fw_priv;
     120             : 
     121             :         /* For a partial read, the buffer must be preallocated. */
     122           0 :         if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
     123             :                 return NULL;
     124             : 
     125             :         /* Only partial reads are allowed to use an offset. */
     126           0 :         if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
     127             :                 return NULL;
     128             : 
     129           0 :         fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
     130           0 :         if (!fw_priv)
     131             :                 return NULL;
     132             : 
     133           0 :         fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
     134           0 :         if (!fw_priv->fw_name) {
     135           0 :                 kfree(fw_priv);
     136           0 :                 return NULL;
     137             :         }
     138             : 
     139           0 :         kref_init(&fw_priv->ref);
     140           0 :         fw_priv->fwc = fwc;
     141           0 :         fw_priv->data = dbuf;
     142           0 :         fw_priv->allocated_size = size;
     143           0 :         fw_priv->offset = offset;
     144           0 :         fw_priv->opt_flags = opt_flags;
     145           0 :         fw_state_init(fw_priv);
     146             : #ifdef CONFIG_FW_LOADER_USER_HELPER
     147             :         INIT_LIST_HEAD(&fw_priv->pending_list);
     148             : #endif
     149             : 
     150             :         pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
     151             : 
     152           0 :         return fw_priv;
     153             : }
     154             : 
     155           0 : static struct fw_priv *__lookup_fw_priv(const char *fw_name)
     156             : {
     157             :         struct fw_priv *tmp;
     158           0 :         struct firmware_cache *fwc = &fw_cache;
     159             : 
     160           0 :         list_for_each_entry(tmp, &fwc->head, list)
     161           0 :                 if (!strcmp(tmp->fw_name, fw_name))
     162             :                         return tmp;
     163             :         return NULL;
     164             : }
     165             : 
     166             : /* Returns 1 for batching firmware requests with the same name */
     167           0 : int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
     168             :                          struct fw_priv **fw_priv, void *dbuf, size_t size,
     169             :                          size_t offset, u32 opt_flags)
     170             : {
     171             :         struct fw_priv *tmp;
     172             : 
     173           0 :         spin_lock(&fwc->lock);
     174             :         /*
     175             :          * Do not merge requests that are marked to be non-cached or
     176             :          * are performing partial reads.
     177             :          */
     178           0 :         if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
     179           0 :                 tmp = __lookup_fw_priv(fw_name);
     180           0 :                 if (tmp) {
     181           0 :                         kref_get(&tmp->ref);
     182           0 :                         spin_unlock(&fwc->lock);
     183           0 :                         *fw_priv = tmp;
     184             :                         pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
     185           0 :                         return 1;
     186             :                 }
     187             :         }
     188             : 
     189           0 :         tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
     190           0 :         if (tmp) {
     191           0 :                 INIT_LIST_HEAD(&tmp->list);
     192           0 :                 if (!(opt_flags & FW_OPT_NOCACHE))
     193           0 :                         list_add(&tmp->list, &fwc->head);
     194             :         }
     195           0 :         spin_unlock(&fwc->lock);
     196             : 
     197           0 :         *fw_priv = tmp;
     198             : 
     199           0 :         return tmp ? 0 : -ENOMEM;
     200             : }
     201             : 
     202           0 : static void __free_fw_priv(struct kref *ref)
     203             :         __releases(&fwc->lock)
     204             : {
     205           0 :         struct fw_priv *fw_priv = to_fw_priv(ref);
     206           0 :         struct firmware_cache *fwc = fw_priv->fwc;
     207             : 
     208             :         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
     209             :                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
     210             :                  (unsigned int)fw_priv->size);
     211             : 
     212           0 :         list_del(&fw_priv->list);
     213           0 :         spin_unlock(&fwc->lock);
     214             : 
     215             :         if (fw_is_paged_buf(fw_priv))
     216             :                 fw_free_paged_buf(fw_priv);
     217           0 :         else if (!fw_priv->allocated_size)
     218           0 :                 vfree(fw_priv->data);
     219             : 
     220           0 :         kfree_const(fw_priv->fw_name);
     221           0 :         kfree(fw_priv);
     222           0 : }
     223             : 
     224           0 : void free_fw_priv(struct fw_priv *fw_priv)
     225             : {
     226           0 :         struct firmware_cache *fwc = fw_priv->fwc;
     227           0 :         spin_lock(&fwc->lock);
     228           0 :         if (!kref_put(&fw_priv->ref, __free_fw_priv))
     229           0 :                 spin_unlock(&fwc->lock);
     230           0 : }
     231             : 
     232             : #ifdef CONFIG_FW_LOADER_PAGED_BUF
     233             : bool fw_is_paged_buf(struct fw_priv *fw_priv)
     234             : {
     235             :         return fw_priv->is_paged_buf;
     236             : }
     237             : 
     238             : void fw_free_paged_buf(struct fw_priv *fw_priv)
     239             : {
     240             :         int i;
     241             : 
     242             :         if (!fw_priv->pages)
     243             :                 return;
     244             : 
     245             :         vunmap(fw_priv->data);
     246             : 
     247             :         for (i = 0; i < fw_priv->nr_pages; i++)
     248             :                 __free_page(fw_priv->pages[i]);
     249             :         kvfree(fw_priv->pages);
     250             :         fw_priv->pages = NULL;
     251             :         fw_priv->page_array_size = 0;
     252             :         fw_priv->nr_pages = 0;
     253             :         fw_priv->data = NULL;
     254             :         fw_priv->size = 0;
     255             : }
     256             : 
     257             : int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
     258             : {
     259             :         /* If the array of pages is too small, grow it */
     260             :         if (fw_priv->page_array_size < pages_needed) {
     261             :                 int new_array_size = max(pages_needed,
     262             :                                          fw_priv->page_array_size * 2);
     263             :                 struct page **new_pages;
     264             : 
     265             :                 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
     266             :                                            GFP_KERNEL);
     267             :                 if (!new_pages)
     268             :                         return -ENOMEM;
     269             :                 memcpy(new_pages, fw_priv->pages,
     270             :                        fw_priv->page_array_size * sizeof(void *));
     271             :                 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
     272             :                        (new_array_size - fw_priv->page_array_size));
     273             :                 kvfree(fw_priv->pages);
     274             :                 fw_priv->pages = new_pages;
     275             :                 fw_priv->page_array_size = new_array_size;
     276             :         }
     277             : 
     278             :         while (fw_priv->nr_pages < pages_needed) {
     279             :                 fw_priv->pages[fw_priv->nr_pages] =
     280             :                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
     281             : 
     282             :                 if (!fw_priv->pages[fw_priv->nr_pages])
     283             :                         return -ENOMEM;
     284             :                 fw_priv->nr_pages++;
     285             :         }
     286             : 
     287             :         return 0;
     288             : }
     289             : 
     290             : int fw_map_paged_buf(struct fw_priv *fw_priv)
     291             : {
     292             :         /* one pages buffer should be mapped/unmapped only once */
     293             :         if (!fw_priv->pages)
     294             :                 return 0;
     295             : 
     296             :         vunmap(fw_priv->data);
     297             :         fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
     298             :                              PAGE_KERNEL_RO);
     299             :         if (!fw_priv->data)
     300             :                 return -ENOMEM;
     301             : 
     302             :         return 0;
     303             : }
     304             : #endif
     305             : 
     306             : /*
     307             :  * ZSTD-compressed firmware support
     308             :  */
     309             : #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
     310             : static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
     311             :                               size_t in_size, const void *in_buffer)
     312             : {
     313             :         size_t len, out_size, workspace_size;
     314             :         void *workspace, *out_buf;
     315             :         zstd_dctx *ctx;
     316             :         int err;
     317             : 
     318             :         if (fw_priv->allocated_size) {
     319             :                 out_size = fw_priv->allocated_size;
     320             :                 out_buf = fw_priv->data;
     321             :         } else {
     322             :                 zstd_frame_header params;
     323             : 
     324             :                 if (zstd_get_frame_header(&params, in_buffer, in_size) ||
     325             :                     params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
     326             :                         dev_dbg(dev, "%s: invalid zstd header\n", __func__);
     327             :                         return -EINVAL;
     328             :                 }
     329             :                 out_size = params.frameContentSize;
     330             :                 out_buf = vzalloc(out_size);
     331             :                 if (!out_buf)
     332             :                         return -ENOMEM;
     333             :         }
     334             : 
     335             :         workspace_size = zstd_dctx_workspace_bound();
     336             :         workspace = kvzalloc(workspace_size, GFP_KERNEL);
     337             :         if (!workspace) {
     338             :                 err = -ENOMEM;
     339             :                 goto error;
     340             :         }
     341             : 
     342             :         ctx = zstd_init_dctx(workspace, workspace_size);
     343             :         if (!ctx) {
     344             :                 dev_dbg(dev, "%s: failed to initialize context\n", __func__);
     345             :                 err = -EINVAL;
     346             :                 goto error;
     347             :         }
     348             : 
     349             :         len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
     350             :         if (zstd_is_error(len)) {
     351             :                 dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
     352             :                         zstd_get_error_code(len));
     353             :                 err = -EINVAL;
     354             :                 goto error;
     355             :         }
     356             : 
     357             :         if (!fw_priv->allocated_size)
     358             :                 fw_priv->data = out_buf;
     359             :         fw_priv->size = len;
     360             :         err = 0;
     361             : 
     362             :  error:
     363             :         kvfree(workspace);
     364             :         if (err && !fw_priv->allocated_size)
     365             :                 vfree(out_buf);
     366             :         return err;
     367             : }
     368             : #endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
     369             : 
     370             : /*
     371             :  * XZ-compressed firmware support
     372             :  */
     373             : #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
     374             : /* show an error and return the standard error code */
     375             : static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
     376             : {
     377             :         if (xz_ret != XZ_STREAM_END) {
     378             :                 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
     379             :                 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
     380             :         }
     381             :         return 0;
     382             : }
     383             : 
     384             : /* single-shot decompression onto the pre-allocated buffer */
     385             : static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
     386             :                                    size_t in_size, const void *in_buffer)
     387             : {
     388             :         struct xz_dec *xz_dec;
     389             :         struct xz_buf xz_buf;
     390             :         enum xz_ret xz_ret;
     391             : 
     392             :         xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
     393             :         if (!xz_dec)
     394             :                 return -ENOMEM;
     395             : 
     396             :         xz_buf.in_size = in_size;
     397             :         xz_buf.in = in_buffer;
     398             :         xz_buf.in_pos = 0;
     399             :         xz_buf.out_size = fw_priv->allocated_size;
     400             :         xz_buf.out = fw_priv->data;
     401             :         xz_buf.out_pos = 0;
     402             : 
     403             :         xz_ret = xz_dec_run(xz_dec, &xz_buf);
     404             :         xz_dec_end(xz_dec);
     405             : 
     406             :         fw_priv->size = xz_buf.out_pos;
     407             :         return fw_decompress_xz_error(dev, xz_ret);
     408             : }
     409             : 
     410             : /* decompression on paged buffer and map it */
     411             : static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
     412             :                                   size_t in_size, const void *in_buffer)
     413             : {
     414             :         struct xz_dec *xz_dec;
     415             :         struct xz_buf xz_buf;
     416             :         enum xz_ret xz_ret;
     417             :         struct page *page;
     418             :         int err = 0;
     419             : 
     420             :         xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
     421             :         if (!xz_dec)
     422             :                 return -ENOMEM;
     423             : 
     424             :         xz_buf.in_size = in_size;
     425             :         xz_buf.in = in_buffer;
     426             :         xz_buf.in_pos = 0;
     427             : 
     428             :         fw_priv->is_paged_buf = true;
     429             :         fw_priv->size = 0;
     430             :         do {
     431             :                 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
     432             :                         err = -ENOMEM;
     433             :                         goto out;
     434             :                 }
     435             : 
     436             :                 /* decompress onto the new allocated page */
     437             :                 page = fw_priv->pages[fw_priv->nr_pages - 1];
     438             :                 xz_buf.out = kmap_local_page(page);
     439             :                 xz_buf.out_pos = 0;
     440             :                 xz_buf.out_size = PAGE_SIZE;
     441             :                 xz_ret = xz_dec_run(xz_dec, &xz_buf);
     442             :                 kunmap_local(xz_buf.out);
     443             :                 fw_priv->size += xz_buf.out_pos;
     444             :                 /* partial decompression means either end or error */
     445             :                 if (xz_buf.out_pos != PAGE_SIZE)
     446             :                         break;
     447             :         } while (xz_ret == XZ_OK);
     448             : 
     449             :         err = fw_decompress_xz_error(dev, xz_ret);
     450             :         if (!err)
     451             :                 err = fw_map_paged_buf(fw_priv);
     452             : 
     453             :  out:
     454             :         xz_dec_end(xz_dec);
     455             :         return err;
     456             : }
     457             : 
     458             : static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
     459             :                             size_t in_size, const void *in_buffer)
     460             : {
     461             :         /* if the buffer is pre-allocated, we can perform in single-shot mode */
     462             :         if (fw_priv->data)
     463             :                 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
     464             :         else
     465             :                 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
     466             : }
     467             : #endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
     468             : 
     469             : /* direct firmware loading support */
     470             : static char fw_path_para[256];
     471             : static const char * const fw_path[] = {
     472             :         fw_path_para,
     473             :         "/lib/firmware/updates/" UTS_RELEASE,
     474             :         "/lib/firmware/updates",
     475             :         "/lib/firmware/" UTS_RELEASE,
     476             :         "/lib/firmware"
     477             : };
     478             : 
     479             : /*
     480             :  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
     481             :  * from kernel command line because firmware_class is generally built in
     482             :  * kernel instead of module.
     483             :  */
     484             : module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
     485             : MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
     486             : 
     487             : static int
     488           0 : fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
     489             :                            const char *suffix,
     490             :                            int (*decompress)(struct device *dev,
     491             :                                              struct fw_priv *fw_priv,
     492             :                                              size_t in_size,
     493             :                                              const void *in_buffer))
     494             : {
     495             :         size_t size;
     496           0 :         int i, len, maxlen = 0;
     497           0 :         int rc = -ENOENT;
     498           0 :         char *path, *nt = NULL;
     499           0 :         size_t msize = INT_MAX;
     500           0 :         void *buffer = NULL;
     501             : 
     502             :         /* Already populated data member means we're loading into a buffer */
     503           0 :         if (!decompress && fw_priv->data) {
     504           0 :                 buffer = fw_priv->data;
     505           0 :                 msize = fw_priv->allocated_size;
     506             :         }
     507             : 
     508           0 :         path = __getname();
     509           0 :         if (!path)
     510             :                 return -ENOMEM;
     511             : 
     512             :         wait_for_initramfs();
     513           0 :         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
     514           0 :                 size_t file_size = 0;
     515           0 :                 size_t *file_size_ptr = NULL;
     516             : 
     517             :                 /* skip the unset customized path */
     518           0 :                 if (!fw_path[i][0])
     519           0 :                         continue;
     520             : 
     521             :                 /* strip off \n from customized path */
     522           0 :                 maxlen = strlen(fw_path[i]);
     523           0 :                 if (i == 0) {
     524           0 :                         nt = strchr(fw_path[i], '\n');
     525           0 :                         if (nt)
     526           0 :                                 maxlen = nt - fw_path[i];
     527             :                 }
     528             : 
     529           0 :                 len = snprintf(path, PATH_MAX, "%.*s/%s%s",
     530             :                                maxlen, fw_path[i],
     531             :                                fw_priv->fw_name, suffix);
     532           0 :                 if (len >= PATH_MAX) {
     533             :                         rc = -ENAMETOOLONG;
     534           0 :                         break;
     535             :                 }
     536             : 
     537           0 :                 fw_priv->size = 0;
     538             : 
     539             :                 /*
     540             :                  * The total file size is only examined when doing a partial
     541             :                  * read; the "full read" case needs to fail if the whole
     542             :                  * firmware was not completely loaded.
     543             :                  */
     544           0 :                 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
     545           0 :                         file_size_ptr = &file_size;
     546             : 
     547             :                 /* load firmware files from the mount namespace of init */
     548           0 :                 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
     549             :                                                        &buffer, msize,
     550             :                                                        file_size_ptr,
     551             :                                                        READING_FIRMWARE);
     552           0 :                 if (rc < 0) {
     553           0 :                         if (rc != -ENOENT)
     554           0 :                                 dev_warn(device, "loading %s failed with error %d\n",
     555             :                                          path, rc);
     556             :                         else
     557             :                                 dev_dbg(device, "loading %s failed for no such file or directory.\n",
     558             :                                          path);
     559           0 :                         continue;
     560             :                 }
     561           0 :                 size = rc;
     562           0 :                 rc = 0;
     563             : 
     564             :                 dev_dbg(device, "Loading firmware from %s\n", path);
     565           0 :                 if (decompress) {
     566             :                         dev_dbg(device, "f/w decompressing %s\n",
     567             :                                 fw_priv->fw_name);
     568           0 :                         rc = decompress(device, fw_priv, size, buffer);
     569             :                         /* discard the superfluous original content */
     570           0 :                         vfree(buffer);
     571           0 :                         buffer = NULL;
     572           0 :                         if (rc) {
     573           0 :                                 fw_free_paged_buf(fw_priv);
     574           0 :                                 continue;
     575             :                         }
     576             :                 } else {
     577             :                         dev_dbg(device, "direct-loading %s\n",
     578             :                                 fw_priv->fw_name);
     579           0 :                         if (!fw_priv->data)
     580           0 :                                 fw_priv->data = buffer;
     581           0 :                         fw_priv->size = size;
     582             :                 }
     583             :                 fw_state_done(fw_priv);
     584             :                 break;
     585             :         }
     586           0 :         __putname(path);
     587             : 
     588           0 :         return rc;
     589             : }
     590             : 
     591             : /* firmware holds the ownership of pages */
     592             : static void firmware_free_data(const struct firmware *fw)
     593             : {
     594             :         /* Loaded directly? */
     595           0 :         if (!fw->priv) {
     596           0 :                 vfree(fw->data);
     597             :                 return;
     598             :         }
     599           0 :         free_fw_priv(fw->priv);
     600             : }
     601             : 
     602             : /* store the pages buffer info firmware from buf */
     603             : static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
     604             : {
     605           0 :         fw->priv = fw_priv;
     606           0 :         fw->size = fw_priv->size;
     607           0 :         fw->data = fw_priv->data;
     608             : 
     609             :         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
     610             :                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
     611             :                  (unsigned int)fw_priv->size);
     612             : }
     613             : 
     614             : #ifdef CONFIG_FW_CACHE
     615           0 : static void fw_name_devm_release(struct device *dev, void *res)
     616             : {
     617           0 :         struct fw_name_devm *fwn = res;
     618             : 
     619             :         if (fwn->magic == (unsigned long)&fw_cache)
     620             :                 pr_debug("%s: fw_name-%s devm-%p released\n",
     621             :                                 __func__, fwn->name, res);
     622           0 :         kfree_const(fwn->name);
     623           0 : }
     624             : 
     625           0 : static int fw_devm_match(struct device *dev, void *res,
     626             :                 void *match_data)
     627             : {
     628           0 :         struct fw_name_devm *fwn = res;
     629             : 
     630           0 :         return (fwn->magic == (unsigned long)&fw_cache) &&
     631           0 :                 !strcmp(fwn->name, match_data);
     632             : }
     633             : 
     634             : static struct fw_name_devm *fw_find_devm_name(struct device *dev,
     635             :                 const char *name)
     636             : {
     637             :         struct fw_name_devm *fwn;
     638             : 
     639           0 :         fwn = devres_find(dev, fw_name_devm_release,
     640             :                           fw_devm_match, (void *)name);
     641             :         return fwn;
     642             : }
     643             : 
     644             : static bool fw_cache_is_setup(struct device *dev, const char *name)
     645             : {
     646             :         struct fw_name_devm *fwn;
     647             : 
     648           0 :         fwn = fw_find_devm_name(dev, name);
     649           0 :         if (fwn)
     650             :                 return true;
     651             : 
     652             :         return false;
     653             : }
     654             : 
     655             : /* add firmware name into devres list */
     656           0 : static int fw_add_devm_name(struct device *dev, const char *name)
     657             : {
     658             :         struct fw_name_devm *fwn;
     659             : 
     660           0 :         if (fw_cache_is_setup(dev, name))
     661             :                 return 0;
     662             : 
     663           0 :         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
     664             :                            GFP_KERNEL);
     665           0 :         if (!fwn)
     666             :                 return -ENOMEM;
     667           0 :         fwn->name = kstrdup_const(name, GFP_KERNEL);
     668           0 :         if (!fwn->name) {
     669           0 :                 devres_free(fwn);
     670           0 :                 return -ENOMEM;
     671             :         }
     672             : 
     673           0 :         fwn->magic = (unsigned long)&fw_cache;
     674           0 :         devres_add(dev, fwn);
     675             : 
     676           0 :         return 0;
     677             : }
     678             : #else
     679             : static bool fw_cache_is_setup(struct device *dev, const char *name)
     680             : {
     681             :         return false;
     682             : }
     683             : 
     684             : static int fw_add_devm_name(struct device *dev, const char *name)
     685             : {
     686             :         return 0;
     687             : }
     688             : #endif
     689             : 
     690           0 : int assign_fw(struct firmware *fw, struct device *device)
     691             : {
     692           0 :         struct fw_priv *fw_priv = fw->priv;
     693             :         int ret;
     694             : 
     695           0 :         mutex_lock(&fw_lock);
     696           0 :         if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
     697           0 :                 mutex_unlock(&fw_lock);
     698           0 :                 return -ENOENT;
     699             :         }
     700             : 
     701             :         /*
     702             :          * add firmware name into devres list so that we can auto cache
     703             :          * and uncache firmware for device.
     704             :          *
     705             :          * device may has been deleted already, but the problem
     706             :          * should be fixed in devres or driver core.
     707             :          */
     708             :         /* don't cache firmware handled without uevent */
     709           0 :         if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
     710             :             !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
     711           0 :                 ret = fw_add_devm_name(device, fw_priv->fw_name);
     712           0 :                 if (ret) {
     713           0 :                         mutex_unlock(&fw_lock);
     714           0 :                         return ret;
     715             :                 }
     716             :         }
     717             : 
     718             :         /*
     719             :          * After caching firmware image is started, let it piggyback
     720             :          * on request firmware.
     721             :          */
     722           0 :         if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
     723           0 :             fw_priv->fwc->state == FW_LOADER_START_CACHE)
     724           0 :                 fw_cache_piggyback_on_request(fw_priv);
     725             : 
     726             :         /* pass the pages buffer to driver at the last minute */
     727           0 :         fw_set_page_data(fw_priv, fw);
     728           0 :         mutex_unlock(&fw_lock);
     729           0 :         return 0;
     730             : }
     731             : 
     732             : /* prepare firmware and firmware_buf structs;
     733             :  * return 0 if a firmware is already assigned, 1 if need to load one,
     734             :  * or a negative error code
     735             :  */
     736             : static int
     737           0 : _request_firmware_prepare(struct firmware **firmware_p, const char *name,
     738             :                           struct device *device, void *dbuf, size_t size,
     739             :                           size_t offset, u32 opt_flags)
     740             : {
     741             :         struct firmware *firmware;
     742             :         struct fw_priv *fw_priv;
     743             :         int ret;
     744             : 
     745           0 :         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
     746           0 :         if (!firmware) {
     747           0 :                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
     748             :                         __func__);
     749           0 :                 return -ENOMEM;
     750             :         }
     751             : 
     752           0 :         if (firmware_request_builtin_buf(firmware, name, dbuf, size)) {
     753             :                 dev_dbg(device, "using built-in %s\n", name);
     754             :                 return 0; /* assigned */
     755             :         }
     756             : 
     757           0 :         ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
     758             :                                    offset, opt_flags);
     759             : 
     760             :         /*
     761             :          * bind with 'priv' now to avoid warning in failure path
     762             :          * of requesting firmware.
     763             :          */
     764           0 :         firmware->priv = fw_priv;
     765             : 
     766           0 :         if (ret > 0) {
     767           0 :                 ret = fw_state_wait(fw_priv);
     768           0 :                 if (!ret) {
     769           0 :                         fw_set_page_data(fw_priv, firmware);
     770           0 :                         return 0; /* assigned */
     771             :                 }
     772             :         }
     773             : 
     774           0 :         if (ret < 0)
     775             :                 return ret;
     776           0 :         return 1; /* need to load */
     777             : }
     778             : 
     779             : /*
     780             :  * Batched requests need only one wake, we need to do this step last due to the
     781             :  * fallback mechanism. The buf is protected with kref_get(), and it won't be
     782             :  * released until the last user calls release_firmware().
     783             :  *
     784             :  * Failed batched requests are possible as well, in such cases we just share
     785             :  * the struct fw_priv and won't release it until all requests are woken
     786             :  * and have gone through this same path.
     787             :  */
     788           0 : static void fw_abort_batch_reqs(struct firmware *fw)
     789             : {
     790             :         struct fw_priv *fw_priv;
     791             : 
     792             :         /* Loaded directly? */
     793           0 :         if (!fw || !fw->priv)
     794             :                 return;
     795             : 
     796           0 :         fw_priv = fw->priv;
     797           0 :         mutex_lock(&fw_lock);
     798           0 :         if (!fw_state_is_aborted(fw_priv))
     799             :                 fw_state_aborted(fw_priv);
     800           0 :         mutex_unlock(&fw_lock);
     801             : }
     802             : 
     803             : #if defined(CONFIG_FW_LOADER_DEBUG)
     804             : #include <crypto/hash.h>
     805             : #include <crypto/sha2.h>
     806             : 
     807             : static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
     808             : {
     809             :         struct shash_desc *shash;
     810             :         struct crypto_shash *alg;
     811             :         u8 *sha256buf;
     812             :         char *outbuf;
     813             : 
     814             :         alg = crypto_alloc_shash("sha256", 0, 0);
     815             :         if (IS_ERR(alg))
     816             :                 return;
     817             : 
     818             :         sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
     819             :         outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL);
     820             :         shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL);
     821             :         if (!sha256buf || !outbuf || !shash)
     822             :                 goto out_free;
     823             : 
     824             :         shash->tfm = alg;
     825             : 
     826             :         if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0)
     827             :                 goto out_shash;
     828             : 
     829             :         for (int i = 0; i < SHA256_DIGEST_SIZE; i++)
     830             :                 sprintf(&outbuf[i * 2], "%02x", sha256buf[i]);
     831             :         outbuf[SHA256_BLOCK_SIZE] = 0;
     832             :         dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf);
     833             : 
     834             : out_shash:
     835             :         crypto_free_shash(alg);
     836             : out_free:
     837             :         kfree(shash);
     838             :         kfree(outbuf);
     839             :         kfree(sha256buf);
     840             : }
     841             : #else
     842             : static void fw_log_firmware_info(const struct firmware *fw, const char *name,
     843             :                                  struct device *device)
     844             : {}
     845             : #endif
     846             : 
     847             : /* called from request_firmware() and request_firmware_work_func() */
     848             : static int
     849           0 : _request_firmware(const struct firmware **firmware_p, const char *name,
     850             :                   struct device *device, void *buf, size_t size,
     851             :                   size_t offset, u32 opt_flags)
     852             : {
     853           0 :         struct firmware *fw = NULL;
     854           0 :         struct cred *kern_cred = NULL;
     855             :         const struct cred *old_cred;
     856           0 :         bool nondirect = false;
     857             :         int ret;
     858             : 
     859           0 :         if (!firmware_p)
     860             :                 return -EINVAL;
     861             : 
     862           0 :         if (!name || name[0] == '\0') {
     863             :                 ret = -EINVAL;
     864             :                 goto out;
     865             :         }
     866             : 
     867           0 :         ret = _request_firmware_prepare(&fw, name, device, buf, size,
     868             :                                         offset, opt_flags);
     869           0 :         if (ret <= 0) /* error or already assigned */
     870             :                 goto out;
     871             : 
     872             :         /*
     873             :          * We are about to try to access the firmware file. Because we may have been
     874             :          * called by a driver when serving an unrelated request from userland, we use
     875             :          * the kernel credentials to read the file.
     876             :          */
     877           0 :         kern_cred = prepare_kernel_cred(&init_task);
     878           0 :         if (!kern_cred) {
     879             :                 ret = -ENOMEM;
     880             :                 goto out;
     881             :         }
     882           0 :         old_cred = override_creds(kern_cred);
     883             : 
     884           0 :         ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
     885             : 
     886             :         /* Only full reads can support decompression, platform, and sysfs. */
     887           0 :         if (!(opt_flags & FW_OPT_PARTIAL))
     888           0 :                 nondirect = true;
     889             : 
     890             : #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
     891             :         if (ret == -ENOENT && nondirect)
     892             :                 ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
     893             :                                                  fw_decompress_zstd);
     894             : #endif
     895             : #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
     896             :         if (ret == -ENOENT && nondirect)
     897             :                 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
     898             :                                                  fw_decompress_xz);
     899             : #endif
     900           0 :         if (ret == -ENOENT && nondirect)
     901           0 :                 ret = firmware_fallback_platform(fw->priv);
     902             : 
     903           0 :         if (ret) {
     904           0 :                 if (!(opt_flags & FW_OPT_NO_WARN))
     905           0 :                         dev_warn(device,
     906             :                                  "Direct firmware load for %s failed with error %d\n",
     907             :                                  name, ret);
     908             :                 if (nondirect)
     909             :                         ret = firmware_fallback_sysfs(fw, name, device,
     910             :                                                       opt_flags, ret);
     911             :         } else
     912           0 :                 ret = assign_fw(fw, device);
     913             : 
     914           0 :         revert_creds(old_cred);
     915             :         put_cred(kern_cred);
     916             : 
     917             : out:
     918           0 :         if (ret < 0) {
     919           0 :                 fw_abort_batch_reqs(fw);
     920           0 :                 release_firmware(fw);
     921           0 :                 fw = NULL;
     922             :         } else {
     923             :                 fw_log_firmware_info(fw, name, device);
     924             :         }
     925             : 
     926           0 :         *firmware_p = fw;
     927           0 :         return ret;
     928             : }
     929             : 
     930             : /**
     931             :  * request_firmware() - send firmware request and wait for it
     932             :  * @firmware_p: pointer to firmware image
     933             :  * @name: name of firmware file
     934             :  * @device: device for which firmware is being loaded
     935             :  *
     936             :  *      @firmware_p will be used to return a firmware image by the name
     937             :  *      of @name for device @device.
     938             :  *
     939             :  *      Should be called from user context where sleeping is allowed.
     940             :  *
     941             :  *      @name will be used as $FIRMWARE in the uevent environment and
     942             :  *      should be distinctive enough not to be confused with any other
     943             :  *      firmware image for this or any other device.
     944             :  *
     945             :  *      Caller must hold the reference count of @device.
     946             :  *
     947             :  *      The function can be called safely inside device's suspend and
     948             :  *      resume callback.
     949             :  **/
     950             : int
     951           0 : request_firmware(const struct firmware **firmware_p, const char *name,
     952             :                  struct device *device)
     953             : {
     954             :         int ret;
     955             : 
     956             :         /* Need to pin this module until return */
     957           0 :         __module_get(THIS_MODULE);
     958           0 :         ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
     959             :                                 FW_OPT_UEVENT);
     960           0 :         module_put(THIS_MODULE);
     961           0 :         return ret;
     962             : }
     963             : EXPORT_SYMBOL(request_firmware);
     964             : 
     965             : /**
     966             :  * firmware_request_nowarn() - request for an optional fw module
     967             :  * @firmware: pointer to firmware image
     968             :  * @name: name of firmware file
     969             :  * @device: device for which firmware is being loaded
     970             :  *
     971             :  * This function is similar in behaviour to request_firmware(), except it
     972             :  * doesn't produce warning messages when the file is not found. The sysfs
     973             :  * fallback mechanism is enabled if direct filesystem lookup fails. However,
     974             :  * failures to find the firmware file with it are still suppressed. It is
     975             :  * therefore up to the driver to check for the return value of this call and to
     976             :  * decide when to inform the users of errors.
     977             :  **/
     978           0 : int firmware_request_nowarn(const struct firmware **firmware, const char *name,
     979             :                             struct device *device)
     980             : {
     981             :         int ret;
     982             : 
     983             :         /* Need to pin this module until return */
     984           0 :         __module_get(THIS_MODULE);
     985           0 :         ret = _request_firmware(firmware, name, device, NULL, 0, 0,
     986             :                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
     987           0 :         module_put(THIS_MODULE);
     988           0 :         return ret;
     989             : }
     990             : EXPORT_SYMBOL_GPL(firmware_request_nowarn);
     991             : 
     992             : /**
     993             :  * request_firmware_direct() - load firmware directly without usermode helper
     994             :  * @firmware_p: pointer to firmware image
     995             :  * @name: name of firmware file
     996             :  * @device: device for which firmware is being loaded
     997             :  *
     998             :  * This function works pretty much like request_firmware(), but this doesn't
     999             :  * fall back to usermode helper even if the firmware couldn't be loaded
    1000             :  * directly from fs.  Hence it's useful for loading optional firmwares, which
    1001             :  * aren't always present, without extra long timeouts of udev.
    1002             :  **/
    1003           0 : int request_firmware_direct(const struct firmware **firmware_p,
    1004             :                             const char *name, struct device *device)
    1005             : {
    1006             :         int ret;
    1007             : 
    1008           0 :         __module_get(THIS_MODULE);
    1009           0 :         ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
    1010             :                                 FW_OPT_UEVENT | FW_OPT_NO_WARN |
    1011             :                                 FW_OPT_NOFALLBACK_SYSFS);
    1012           0 :         module_put(THIS_MODULE);
    1013           0 :         return ret;
    1014             : }
    1015             : EXPORT_SYMBOL_GPL(request_firmware_direct);
    1016             : 
    1017             : /**
    1018             :  * firmware_request_platform() - request firmware with platform-fw fallback
    1019             :  * @firmware: pointer to firmware image
    1020             :  * @name: name of firmware file
    1021             :  * @device: device for which firmware is being loaded
    1022             :  *
    1023             :  * This function is similar in behaviour to request_firmware, except that if
    1024             :  * direct filesystem lookup fails, it will fallback to looking for a copy of the
    1025             :  * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
    1026             :  **/
    1027           0 : int firmware_request_platform(const struct firmware **firmware,
    1028             :                               const char *name, struct device *device)
    1029             : {
    1030             :         int ret;
    1031             : 
    1032             :         /* Need to pin this module until return */
    1033           0 :         __module_get(THIS_MODULE);
    1034           0 :         ret = _request_firmware(firmware, name, device, NULL, 0, 0,
    1035             :                                 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
    1036           0 :         module_put(THIS_MODULE);
    1037           0 :         return ret;
    1038             : }
    1039             : EXPORT_SYMBOL_GPL(firmware_request_platform);
    1040             : 
    1041             : /**
    1042             :  * firmware_request_cache() - cache firmware for suspend so resume can use it
    1043             :  * @name: name of firmware file
    1044             :  * @device: device for which firmware should be cached for
    1045             :  *
    1046             :  * There are some devices with an optimization that enables the device to not
    1047             :  * require loading firmware on system reboot. This optimization may still
    1048             :  * require the firmware present on resume from suspend. This routine can be
    1049             :  * used to ensure the firmware is present on resume from suspend in these
    1050             :  * situations. This helper is not compatible with drivers which use
    1051             :  * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
    1052             :  **/
    1053           0 : int firmware_request_cache(struct device *device, const char *name)
    1054             : {
    1055             :         int ret;
    1056             : 
    1057           0 :         mutex_lock(&fw_lock);
    1058           0 :         ret = fw_add_devm_name(device, name);
    1059           0 :         mutex_unlock(&fw_lock);
    1060             : 
    1061           0 :         return ret;
    1062             : }
    1063             : EXPORT_SYMBOL_GPL(firmware_request_cache);
    1064             : 
    1065             : /**
    1066             :  * request_firmware_into_buf() - load firmware into a previously allocated buffer
    1067             :  * @firmware_p: pointer to firmware image
    1068             :  * @name: name of firmware file
    1069             :  * @device: device for which firmware is being loaded and DMA region allocated
    1070             :  * @buf: address of buffer to load firmware into
    1071             :  * @size: size of buffer
    1072             :  *
    1073             :  * This function works pretty much like request_firmware(), but it doesn't
    1074             :  * allocate a buffer to hold the firmware data. Instead, the firmware
    1075             :  * is loaded directly into the buffer pointed to by @buf and the @firmware_p
    1076             :  * data member is pointed at @buf.
    1077             :  *
    1078             :  * This function doesn't cache firmware either.
    1079             :  */
    1080             : int
    1081           0 : request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
    1082             :                           struct device *device, void *buf, size_t size)
    1083             : {
    1084             :         int ret;
    1085             : 
    1086           0 :         if (fw_cache_is_setup(device, name))
    1087             :                 return -EOPNOTSUPP;
    1088             : 
    1089           0 :         __module_get(THIS_MODULE);
    1090           0 :         ret = _request_firmware(firmware_p, name, device, buf, size, 0,
    1091             :                                 FW_OPT_UEVENT | FW_OPT_NOCACHE);
    1092           0 :         module_put(THIS_MODULE);
    1093           0 :         return ret;
    1094             : }
    1095             : EXPORT_SYMBOL(request_firmware_into_buf);
    1096             : 
    1097             : /**
    1098             :  * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
    1099             :  * @firmware_p: pointer to firmware image
    1100             :  * @name: name of firmware file
    1101             :  * @device: device for which firmware is being loaded and DMA region allocated
    1102             :  * @buf: address of buffer to load firmware into
    1103             :  * @size: size of buffer
    1104             :  * @offset: offset into file to read
    1105             :  *
    1106             :  * This function works pretty much like request_firmware_into_buf except
    1107             :  * it allows a partial read of the file.
    1108             :  */
    1109             : int
    1110           0 : request_partial_firmware_into_buf(const struct firmware **firmware_p,
    1111             :                                   const char *name, struct device *device,
    1112             :                                   void *buf, size_t size, size_t offset)
    1113             : {
    1114             :         int ret;
    1115             : 
    1116           0 :         if (fw_cache_is_setup(device, name))
    1117             :                 return -EOPNOTSUPP;
    1118             : 
    1119           0 :         __module_get(THIS_MODULE);
    1120           0 :         ret = _request_firmware(firmware_p, name, device, buf, size, offset,
    1121             :                                 FW_OPT_UEVENT | FW_OPT_NOCACHE |
    1122             :                                 FW_OPT_PARTIAL);
    1123           0 :         module_put(THIS_MODULE);
    1124           0 :         return ret;
    1125             : }
    1126             : EXPORT_SYMBOL(request_partial_firmware_into_buf);
    1127             : 
    1128             : /**
    1129             :  * release_firmware() - release the resource associated with a firmware image
    1130             :  * @fw: firmware resource to release
    1131             :  **/
    1132           0 : void release_firmware(const struct firmware *fw)
    1133             : {
    1134           0 :         if (fw) {
    1135           0 :                 if (!firmware_is_builtin(fw))
    1136           0 :                         firmware_free_data(fw);
    1137           0 :                 kfree(fw);
    1138             :         }
    1139           0 : }
    1140             : EXPORT_SYMBOL(release_firmware);
    1141             : 
    1142             : /* Async support */
    1143             : struct firmware_work {
    1144             :         struct work_struct work;
    1145             :         struct module *module;
    1146             :         const char *name;
    1147             :         struct device *device;
    1148             :         void *context;
    1149             :         void (*cont)(const struct firmware *fw, void *context);
    1150             :         u32 opt_flags;
    1151             : };
    1152             : 
    1153           0 : static void request_firmware_work_func(struct work_struct *work)
    1154             : {
    1155             :         struct firmware_work *fw_work;
    1156             :         const struct firmware *fw;
    1157             : 
    1158           0 :         fw_work = container_of(work, struct firmware_work, work);
    1159             : 
    1160           0 :         _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
    1161             :                           fw_work->opt_flags);
    1162           0 :         fw_work->cont(fw, fw_work->context);
    1163           0 :         put_device(fw_work->device); /* taken in request_firmware_nowait() */
    1164             : 
    1165           0 :         module_put(fw_work->module);
    1166           0 :         kfree_const(fw_work->name);
    1167           0 :         kfree(fw_work);
    1168           0 : }
    1169             : 
    1170             : /**
    1171             :  * request_firmware_nowait() - asynchronous version of request_firmware
    1172             :  * @module: module requesting the firmware
    1173             :  * @uevent: sends uevent to copy the firmware image if this flag
    1174             :  *      is non-zero else the firmware copy must be done manually.
    1175             :  * @name: name of firmware file
    1176             :  * @device: device for which firmware is being loaded
    1177             :  * @gfp: allocation flags
    1178             :  * @context: will be passed over to @cont, and
    1179             :  *      @fw may be %NULL if firmware request fails.
    1180             :  * @cont: function will be called asynchronously when the firmware
    1181             :  *      request is over.
    1182             :  *
    1183             :  *      Caller must hold the reference count of @device.
    1184             :  *
    1185             :  *      Asynchronous variant of request_firmware() for user contexts:
    1186             :  *              - sleep for as small periods as possible since it may
    1187             :  *                increase kernel boot time of built-in device drivers
    1188             :  *                requesting firmware in their ->probe() methods, if
    1189             :  *                @gfp is GFP_KERNEL.
    1190             :  *
    1191             :  *              - can't sleep at all if @gfp is GFP_ATOMIC.
    1192             :  **/
    1193             : int
    1194           0 : request_firmware_nowait(
    1195             :         struct module *module, bool uevent,
    1196             :         const char *name, struct device *device, gfp_t gfp, void *context,
    1197             :         void (*cont)(const struct firmware *fw, void *context))
    1198             : {
    1199             :         struct firmware_work *fw_work;
    1200             : 
    1201           0 :         fw_work = kzalloc(sizeof(struct firmware_work), gfp);
    1202           0 :         if (!fw_work)
    1203             :                 return -ENOMEM;
    1204             : 
    1205           0 :         fw_work->module = module;
    1206           0 :         fw_work->name = kstrdup_const(name, gfp);
    1207           0 :         if (!fw_work->name) {
    1208           0 :                 kfree(fw_work);
    1209           0 :                 return -ENOMEM;
    1210             :         }
    1211           0 :         fw_work->device = device;
    1212           0 :         fw_work->context = context;
    1213           0 :         fw_work->cont = cont;
    1214           0 :         fw_work->opt_flags = FW_OPT_NOWAIT |
    1215             :                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
    1216             : 
    1217           0 :         if (!uevent && fw_cache_is_setup(device, name)) {
    1218           0 :                 kfree_const(fw_work->name);
    1219           0 :                 kfree(fw_work);
    1220           0 :                 return -EOPNOTSUPP;
    1221             :         }
    1222             : 
    1223           0 :         if (!try_module_get(module)) {
    1224             :                 kfree_const(fw_work->name);
    1225             :                 kfree(fw_work);
    1226             :                 return -EFAULT;
    1227             :         }
    1228             : 
    1229           0 :         get_device(fw_work->device);
    1230           0 :         INIT_WORK(&fw_work->work, request_firmware_work_func);
    1231           0 :         schedule_work(&fw_work->work);
    1232           0 :         return 0;
    1233             : }
    1234             : EXPORT_SYMBOL(request_firmware_nowait);
    1235             : 
    1236             : #ifdef CONFIG_FW_CACHE
    1237             : static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
    1238             : 
    1239             : /**
    1240             :  * cache_firmware() - cache one firmware image in kernel memory space
    1241             :  * @fw_name: the firmware image name
    1242             :  *
    1243             :  * Cache firmware in kernel memory so that drivers can use it when
    1244             :  * system isn't ready for them to request firmware image from userspace.
    1245             :  * Once it returns successfully, driver can use request_firmware or its
    1246             :  * nowait version to get the cached firmware without any interacting
    1247             :  * with userspace
    1248             :  *
    1249             :  * Return 0 if the firmware image has been cached successfully
    1250             :  * Return !0 otherwise
    1251             :  *
    1252             :  */
    1253           0 : static int cache_firmware(const char *fw_name)
    1254             : {
    1255             :         int ret;
    1256             :         const struct firmware *fw;
    1257             : 
    1258           0 :         pr_debug("%s: %s\n", __func__, fw_name);
    1259             : 
    1260           0 :         ret = request_firmware(&fw, fw_name, NULL);
    1261           0 :         if (!ret)
    1262           0 :                 kfree(fw);
    1263             : 
    1264             :         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
    1265             : 
    1266           0 :         return ret;
    1267             : }
    1268             : 
    1269             : static struct fw_priv *lookup_fw_priv(const char *fw_name)
    1270             : {
    1271             :         struct fw_priv *tmp;
    1272           0 :         struct firmware_cache *fwc = &fw_cache;
    1273             : 
    1274           0 :         spin_lock(&fwc->lock);
    1275           0 :         tmp = __lookup_fw_priv(fw_name);
    1276           0 :         spin_unlock(&fwc->lock);
    1277             : 
    1278             :         return tmp;
    1279             : }
    1280             : 
    1281             : /**
    1282             :  * uncache_firmware() - remove one cached firmware image
    1283             :  * @fw_name: the firmware image name
    1284             :  *
    1285             :  * Uncache one firmware image which has been cached successfully
    1286             :  * before.
    1287             :  *
    1288             :  * Return 0 if the firmware cache has been removed successfully
    1289             :  * Return !0 otherwise
    1290             :  *
    1291             :  */
    1292           0 : static int uncache_firmware(const char *fw_name)
    1293             : {
    1294             :         struct fw_priv *fw_priv;
    1295             :         struct firmware fw;
    1296             : 
    1297             :         pr_debug("%s: %s\n", __func__, fw_name);
    1298             : 
    1299           0 :         if (firmware_request_builtin(&fw, fw_name))
    1300             :                 return 0;
    1301             : 
    1302           0 :         fw_priv = lookup_fw_priv(fw_name);
    1303           0 :         if (fw_priv) {
    1304           0 :                 free_fw_priv(fw_priv);
    1305           0 :                 return 0;
    1306             :         }
    1307             : 
    1308             :         return -EINVAL;
    1309             : }
    1310             : 
    1311           0 : static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
    1312             : {
    1313             :         struct fw_cache_entry *fce;
    1314             : 
    1315           0 :         fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
    1316           0 :         if (!fce)
    1317             :                 goto exit;
    1318             : 
    1319           0 :         fce->name = kstrdup_const(name, GFP_ATOMIC);
    1320           0 :         if (!fce->name) {
    1321           0 :                 kfree(fce);
    1322           0 :                 fce = NULL;
    1323           0 :                 goto exit;
    1324             :         }
    1325             : exit:
    1326           0 :         return fce;
    1327             : }
    1328             : 
    1329           0 : static int __fw_entry_found(const char *name)
    1330             : {
    1331           0 :         struct firmware_cache *fwc = &fw_cache;
    1332             :         struct fw_cache_entry *fce;
    1333             : 
    1334           0 :         list_for_each_entry(fce, &fwc->fw_names, list) {
    1335           0 :                 if (!strcmp(fce->name, name))
    1336             :                         return 1;
    1337             :         }
    1338             :         return 0;
    1339             : }
    1340             : 
    1341           0 : static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
    1342             : {
    1343           0 :         const char *name = fw_priv->fw_name;
    1344           0 :         struct firmware_cache *fwc = fw_priv->fwc;
    1345             :         struct fw_cache_entry *fce;
    1346             : 
    1347           0 :         spin_lock(&fwc->name_lock);
    1348           0 :         if (__fw_entry_found(name))
    1349             :                 goto found;
    1350             : 
    1351           0 :         fce = alloc_fw_cache_entry(name);
    1352           0 :         if (fce) {
    1353           0 :                 list_add(&fce->list, &fwc->fw_names);
    1354           0 :                 kref_get(&fw_priv->ref);
    1355             :                 pr_debug("%s: fw: %s\n", __func__, name);
    1356             :         }
    1357             : found:
    1358           0 :         spin_unlock(&fwc->name_lock);
    1359           0 : }
    1360             : 
    1361             : static void free_fw_cache_entry(struct fw_cache_entry *fce)
    1362             : {
    1363           0 :         kfree_const(fce->name);
    1364           0 :         kfree(fce);
    1365             : }
    1366             : 
    1367           0 : static void __async_dev_cache_fw_image(void *fw_entry,
    1368             :                                        async_cookie_t cookie)
    1369             : {
    1370           0 :         struct fw_cache_entry *fce = fw_entry;
    1371           0 :         struct firmware_cache *fwc = &fw_cache;
    1372             :         int ret;
    1373             : 
    1374           0 :         ret = cache_firmware(fce->name);
    1375           0 :         if (ret) {
    1376           0 :                 spin_lock(&fwc->name_lock);
    1377           0 :                 list_del(&fce->list);
    1378           0 :                 spin_unlock(&fwc->name_lock);
    1379             : 
    1380             :                 free_fw_cache_entry(fce);
    1381             :         }
    1382           0 : }
    1383             : 
    1384             : /* called with dev->devres_lock held */
    1385           0 : static void dev_create_fw_entry(struct device *dev, void *res,
    1386             :                                 void *data)
    1387             : {
    1388           0 :         struct fw_name_devm *fwn = res;
    1389           0 :         const char *fw_name = fwn->name;
    1390           0 :         struct list_head *head = data;
    1391             :         struct fw_cache_entry *fce;
    1392             : 
    1393           0 :         fce = alloc_fw_cache_entry(fw_name);
    1394           0 :         if (fce)
    1395           0 :                 list_add(&fce->list, head);
    1396           0 : }
    1397             : 
    1398           0 : static int devm_name_match(struct device *dev, void *res,
    1399             :                            void *match_data)
    1400             : {
    1401           0 :         struct fw_name_devm *fwn = res;
    1402           0 :         return (fwn->magic == (unsigned long)match_data);
    1403             : }
    1404             : 
    1405           0 : static void dev_cache_fw_image(struct device *dev, void *data)
    1406             : {
    1407           0 :         LIST_HEAD(todo);
    1408             :         struct fw_cache_entry *fce;
    1409             :         struct fw_cache_entry *fce_next;
    1410           0 :         struct firmware_cache *fwc = &fw_cache;
    1411             : 
    1412           0 :         devres_for_each_res(dev, fw_name_devm_release,
    1413             :                             devm_name_match, &fw_cache,
    1414             :                             dev_create_fw_entry, &todo);
    1415             : 
    1416           0 :         list_for_each_entry_safe(fce, fce_next, &todo, list) {
    1417           0 :                 list_del(&fce->list);
    1418             : 
    1419           0 :                 spin_lock(&fwc->name_lock);
    1420             :                 /* only one cache entry for one firmware */
    1421           0 :                 if (!__fw_entry_found(fce->name)) {
    1422           0 :                         list_add(&fce->list, &fwc->fw_names);
    1423             :                 } else {
    1424           0 :                         free_fw_cache_entry(fce);
    1425           0 :                         fce = NULL;
    1426             :                 }
    1427           0 :                 spin_unlock(&fwc->name_lock);
    1428             : 
    1429           0 :                 if (fce)
    1430             :                         async_schedule_domain(__async_dev_cache_fw_image,
    1431             :                                               (void *)fce,
    1432             :                                               &fw_cache_domain);
    1433             :         }
    1434           0 : }
    1435             : 
    1436           0 : static void __device_uncache_fw_images(void)
    1437             : {
    1438           0 :         struct firmware_cache *fwc = &fw_cache;
    1439             :         struct fw_cache_entry *fce;
    1440             : 
    1441           0 :         spin_lock(&fwc->name_lock);
    1442           0 :         while (!list_empty(&fwc->fw_names)) {
    1443           0 :                 fce = list_entry(fwc->fw_names.next,
    1444             :                                 struct fw_cache_entry, list);
    1445           0 :                 list_del(&fce->list);
    1446           0 :                 spin_unlock(&fwc->name_lock);
    1447             : 
    1448           0 :                 uncache_firmware(fce->name);
    1449           0 :                 free_fw_cache_entry(fce);
    1450             : 
    1451           0 :                 spin_lock(&fwc->name_lock);
    1452             :         }
    1453           0 :         spin_unlock(&fwc->name_lock);
    1454           0 : }
    1455             : 
    1456             : /**
    1457             :  * device_cache_fw_images() - cache devices' firmware
    1458             :  *
    1459             :  * If one device called request_firmware or its nowait version
    1460             :  * successfully before, the firmware names are recored into the
    1461             :  * device's devres link list, so device_cache_fw_images can call
    1462             :  * cache_firmware() to cache these firmwares for the device,
    1463             :  * then the device driver can load its firmwares easily at
    1464             :  * time when system is not ready to complete loading firmware.
    1465             :  */
    1466           0 : static void device_cache_fw_images(void)
    1467             : {
    1468           0 :         struct firmware_cache *fwc = &fw_cache;
    1469           0 :         DEFINE_WAIT(wait);
    1470             : 
    1471             :         pr_debug("%s\n", __func__);
    1472             : 
    1473             :         /* cancel uncache work */
    1474           0 :         cancel_delayed_work_sync(&fwc->work);
    1475             : 
    1476             :         fw_fallback_set_cache_timeout();
    1477             : 
    1478           0 :         mutex_lock(&fw_lock);
    1479           0 :         fwc->state = FW_LOADER_START_CACHE;
    1480           0 :         dpm_for_each_dev(NULL, dev_cache_fw_image);
    1481           0 :         mutex_unlock(&fw_lock);
    1482             : 
    1483             :         /* wait for completion of caching firmware for all devices */
    1484           0 :         async_synchronize_full_domain(&fw_cache_domain);
    1485             : 
    1486             :         fw_fallback_set_default_timeout();
    1487           0 : }
    1488             : 
    1489             : /**
    1490             :  * device_uncache_fw_images() - uncache devices' firmware
    1491             :  *
    1492             :  * uncache all firmwares which have been cached successfully
    1493             :  * by device_uncache_fw_images earlier
    1494             :  */
    1495             : static void device_uncache_fw_images(void)
    1496             : {
    1497             :         pr_debug("%s\n", __func__);
    1498           0 :         __device_uncache_fw_images();
    1499             : }
    1500             : 
    1501           0 : static void device_uncache_fw_images_work(struct work_struct *work)
    1502             : {
    1503             :         device_uncache_fw_images();
    1504           0 : }
    1505             : 
    1506             : /**
    1507             :  * device_uncache_fw_images_delay() - uncache devices firmwares
    1508             :  * @delay: number of milliseconds to delay uncache device firmwares
    1509             :  *
    1510             :  * uncache all devices's firmwares which has been cached successfully
    1511             :  * by device_cache_fw_images after @delay milliseconds.
    1512             :  */
    1513           0 : static void device_uncache_fw_images_delay(unsigned long delay)
    1514             : {
    1515           0 :         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
    1516             :                            msecs_to_jiffies(delay));
    1517           0 : }
    1518             : 
    1519           0 : static int fw_pm_notify(struct notifier_block *notify_block,
    1520             :                         unsigned long mode, void *unused)
    1521             : {
    1522             :         switch (mode) {
    1523             :         case PM_HIBERNATION_PREPARE:
    1524             :         case PM_SUSPEND_PREPARE:
    1525             :         case PM_RESTORE_PREPARE:
    1526             :                 /*
    1527             :                  * kill pending fallback requests with a custom fallback
    1528             :                  * to avoid stalling suspend.
    1529             :                  */
    1530           0 :                 kill_pending_fw_fallback_reqs(true);
    1531           0 :                 device_cache_fw_images();
    1532           0 :                 break;
    1533             : 
    1534             :         case PM_POST_SUSPEND:
    1535             :         case PM_POST_HIBERNATION:
    1536             :         case PM_POST_RESTORE:
    1537             :                 /*
    1538             :                  * In case that system sleep failed and syscore_suspend is
    1539             :                  * not called.
    1540             :                  */
    1541           0 :                 mutex_lock(&fw_lock);
    1542           0 :                 fw_cache.state = FW_LOADER_NO_CACHE;
    1543           0 :                 mutex_unlock(&fw_lock);
    1544             : 
    1545           0 :                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
    1546           0 :                 break;
    1547             :         }
    1548             : 
    1549           0 :         return 0;
    1550             : }
    1551             : 
    1552             : /* stop caching firmware once syscore_suspend is reached */
    1553           0 : static int fw_suspend(void)
    1554             : {
    1555           0 :         fw_cache.state = FW_LOADER_NO_CACHE;
    1556           0 :         return 0;
    1557             : }
    1558             : 
    1559             : static struct syscore_ops fw_syscore_ops = {
    1560             :         .suspend = fw_suspend,
    1561             : };
    1562             : 
    1563           1 : static int __init register_fw_pm_ops(void)
    1564             : {
    1565             :         int ret;
    1566             : 
    1567           1 :         spin_lock_init(&fw_cache.name_lock);
    1568           1 :         INIT_LIST_HEAD(&fw_cache.fw_names);
    1569             : 
    1570           2 :         INIT_DELAYED_WORK(&fw_cache.work,
    1571             :                           device_uncache_fw_images_work);
    1572             : 
    1573           1 :         fw_cache.pm_notify.notifier_call = fw_pm_notify;
    1574           1 :         ret = register_pm_notifier(&fw_cache.pm_notify);
    1575           1 :         if (ret)
    1576             :                 return ret;
    1577             : 
    1578           1 :         register_syscore_ops(&fw_syscore_ops);
    1579             : 
    1580           1 :         return ret;
    1581             : }
    1582             : 
    1583             : static inline void unregister_fw_pm_ops(void)
    1584             : {
    1585           0 :         unregister_syscore_ops(&fw_syscore_ops);
    1586           0 :         unregister_pm_notifier(&fw_cache.pm_notify);
    1587             : }
    1588             : #else
    1589             : static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
    1590             : {
    1591             : }
    1592             : static inline int register_fw_pm_ops(void)
    1593             : {
    1594             :         return 0;
    1595             : }
    1596             : static inline void unregister_fw_pm_ops(void)
    1597             : {
    1598             : }
    1599             : #endif
    1600             : 
    1601           1 : static void __init fw_cache_init(void)
    1602             : {
    1603           1 :         spin_lock_init(&fw_cache.lock);
    1604           1 :         INIT_LIST_HEAD(&fw_cache.head);
    1605           1 :         fw_cache.state = FW_LOADER_NO_CACHE;
    1606           1 : }
    1607             : 
    1608           1 : static int fw_shutdown_notify(struct notifier_block *unused1,
    1609             :                               unsigned long unused2, void *unused3)
    1610             : {
    1611             :         /*
    1612             :          * Kill all pending fallback requests to avoid both stalling shutdown,
    1613             :          * and avoid a deadlock with the usermode_lock.
    1614             :          */
    1615           1 :         kill_pending_fw_fallback_reqs(false);
    1616             : 
    1617           1 :         return NOTIFY_DONE;
    1618             : }
    1619             : 
    1620             : static struct notifier_block fw_shutdown_nb = {
    1621             :         .notifier_call = fw_shutdown_notify,
    1622             : };
    1623             : 
    1624           1 : static int __init firmware_class_init(void)
    1625             : {
    1626             :         int ret;
    1627             : 
    1628             :         /* No need to unfold these on exit */
    1629           1 :         fw_cache_init();
    1630             : 
    1631           1 :         ret = register_fw_pm_ops();
    1632           1 :         if (ret)
    1633             :                 return ret;
    1634             : 
    1635           1 :         ret = register_reboot_notifier(&fw_shutdown_nb);
    1636           1 :         if (ret)
    1637             :                 goto out;
    1638             : 
    1639             :         return register_sysfs_loader();
    1640             : 
    1641             : out:
    1642             :         unregister_fw_pm_ops();
    1643           0 :         return ret;
    1644             : }
    1645             : 
    1646           0 : static void __exit firmware_class_exit(void)
    1647             : {
    1648             :         unregister_fw_pm_ops();
    1649           0 :         unregister_reboot_notifier(&fw_shutdown_nb);
    1650             :         unregister_sysfs_loader();
    1651           0 : }
    1652             : 
    1653             : fs_initcall(firmware_class_init);
    1654             : module_exit(firmware_class_exit);

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