diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/firmware/efi/capsule.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'drivers/firmware/efi/capsule.c')
| -rw-r--r-- | drivers/firmware/efi/capsule.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/firmware/efi/capsule.c b/drivers/firmware/efi/capsule.c new file mode 100644 index 000000000..dd6252638 --- /dev/null +++ b/drivers/firmware/efi/capsule.c @@ -0,0 +1,315 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * EFI capsule support. + * + * Copyright 2013 Intel Corporation; author Matt Fleming + */ + +#define pr_fmt(fmt) "efi: " fmt + +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/highmem.h> +#include <linux/efi.h> +#include <linux/vmalloc.h> +#include <asm/efi.h> +#include <asm/io.h> + +typedef struct { + u64 length; + u64 data; +} efi_capsule_block_desc_t; + +static bool capsule_pending; +static bool stop_capsules; +static int efi_reset_type = -1; + +/* + * capsule_mutex serialises access to both capsule_pending and + * efi_reset_type and stop_capsules. + */ +static DEFINE_MUTEX(capsule_mutex); + +/** + * efi_capsule_pending - has a capsule been passed to the firmware? + * @reset_type: store the type of EFI reset if capsule is pending + * + * To ensure that the registered capsule is processed correctly by the + * firmware we need to perform a specific type of reset. If a capsule is + * pending return the reset type in @reset_type. + * + * This function will race with callers of efi_capsule_update(), for + * example, calling this function while somebody else is in + * efi_capsule_update() but hasn't reached efi_capsue_update_locked() + * will miss the updates to capsule_pending and efi_reset_type after + * efi_capsule_update_locked() completes. + * + * A non-racy use is from platform reboot code because we use + * system_state to ensure no capsules can be sent to the firmware once + * we're at SYSTEM_RESTART. See efi_capsule_update_locked(). + */ +bool efi_capsule_pending(int *reset_type) +{ + if (!capsule_pending) + return false; + + if (reset_type) + *reset_type = efi_reset_type; + + return true; +} + +/* + * Whitelist of EFI capsule flags that we support. + * + * We do not handle EFI_CAPSULE_INITIATE_RESET because that would + * require us to prepare the kernel for reboot. Refuse to load any + * capsules with that flag and any other flags that we do not know how + * to handle. + */ +#define EFI_CAPSULE_SUPPORTED_FLAG_MASK \ + (EFI_CAPSULE_PERSIST_ACROSS_RESET | EFI_CAPSULE_POPULATE_SYSTEM_TABLE) + +/** + * efi_capsule_supported - does the firmware support the capsule? + * @guid: vendor guid of capsule + * @flags: capsule flags + * @size: size of capsule data + * @reset: the reset type required for this capsule + * + * Check whether a capsule with @flags is supported by the firmware + * and that @size doesn't exceed the maximum size for a capsule. + * + * No attempt is made to check @reset against the reset type required + * by any pending capsules because of the races involved. + */ +int efi_capsule_supported(efi_guid_t guid, u32 flags, size_t size, int *reset) +{ + efi_capsule_header_t capsule; + efi_capsule_header_t *cap_list[] = { &capsule }; + efi_status_t status; + u64 max_size; + + if (flags & ~EFI_CAPSULE_SUPPORTED_FLAG_MASK) + return -EINVAL; + + capsule.headersize = capsule.imagesize = sizeof(capsule); + memcpy(&capsule.guid, &guid, sizeof(efi_guid_t)); + capsule.flags = flags; + + status = efi.query_capsule_caps(cap_list, 1, &max_size, reset); + if (status != EFI_SUCCESS) + return efi_status_to_err(status); + + if (size > max_size) + return -ENOSPC; + + return 0; +} +EXPORT_SYMBOL_GPL(efi_capsule_supported); + +/* + * Every scatter gather list (block descriptor) page must end with a + * continuation pointer. The last continuation pointer of the last + * page must be zero to mark the end of the chain. + */ +#define SGLIST_PER_PAGE ((PAGE_SIZE / sizeof(efi_capsule_block_desc_t)) - 1) + +/* + * How many scatter gather list (block descriptor) pages do we need + * to map @count pages? + */ +static inline unsigned int sg_pages_num(unsigned int count) +{ + return DIV_ROUND_UP(count, SGLIST_PER_PAGE); +} + +/** + * efi_capsule_update_locked - pass a single capsule to the firmware + * @capsule: capsule to send to the firmware + * @sg_pages: array of scatter gather (block descriptor) pages + * @reset: the reset type required for @capsule + * + * Since this function must be called under capsule_mutex check + * whether efi_reset_type will conflict with @reset, and atomically + * set it and capsule_pending if a capsule was successfully sent to + * the firmware. + * + * We also check to see if the system is about to restart, and if so, + * abort. This avoids races between efi_capsule_update() and + * efi_capsule_pending(). + */ +static int +efi_capsule_update_locked(efi_capsule_header_t *capsule, + struct page **sg_pages, int reset) +{ + efi_physical_addr_t sglist_phys; + efi_status_t status; + + lockdep_assert_held(&capsule_mutex); + + /* + * If someone has already registered a capsule that requires a + * different reset type, we're out of luck and must abort. + */ + if (efi_reset_type >= 0 && efi_reset_type != reset) { + pr_err("Conflicting capsule reset type %d (%d).\n", + reset, efi_reset_type); + return -EINVAL; + } + + /* + * If the system is getting ready to restart it may have + * called efi_capsule_pending() to make decisions (such as + * whether to force an EFI reboot), and we're racing against + * that call. Abort in that case. + */ + if (unlikely(stop_capsules)) { + pr_warn("Capsule update raced with reboot, aborting.\n"); + return -EINVAL; + } + + sglist_phys = page_to_phys(sg_pages[0]); + + status = efi.update_capsule(&capsule, 1, sglist_phys); + if (status == EFI_SUCCESS) { + capsule_pending = true; + efi_reset_type = reset; + } + + return efi_status_to_err(status); +} + +/** + * efi_capsule_update - send a capsule to the firmware + * @capsule: capsule to send to firmware + * @pages: an array of capsule data pages + * + * Build a scatter gather list with EFI capsule block descriptors to + * map the capsule described by @capsule with its data in @pages and + * send it to the firmware via the UpdateCapsule() runtime service. + * + * @capsule must be a virtual mapping of the complete capsule update in the + * kernel address space, as the capsule can be consumed immediately. + * A capsule_header_t that describes the entire contents of the capsule + * must be at the start of the first data page. + * + * Even though this function will validate that the firmware supports + * the capsule guid, users will likely want to check that + * efi_capsule_supported() returns true before calling this function + * because it makes it easier to print helpful error messages. + * + * If the capsule is successfully submitted to the firmware, any + * subsequent calls to efi_capsule_pending() will return true. @pages + * must not be released or modified if this function returns + * successfully. + * + * Callers must be prepared for this function to fail, which can + * happen if we raced with system reboot or if there is already a + * pending capsule that has a reset type that conflicts with the one + * required by @capsule. Do NOT use efi_capsule_pending() to detect + * this conflict since that would be racy. Instead, submit the capsule + * to efi_capsule_update() and check the return value. + * + * Return 0 on success, a converted EFI status code on failure. + */ +int efi_capsule_update(efi_capsule_header_t *capsule, phys_addr_t *pages) +{ + u32 imagesize = capsule->imagesize; + efi_guid_t guid = capsule->guid; + unsigned int count, sg_count; + u32 flags = capsule->flags; + struct page **sg_pages; + int rv, reset_type; + int i, j; + + rv = efi_capsule_supported(guid, flags, imagesize, &reset_type); + if (rv) + return rv; + + count = DIV_ROUND_UP(imagesize, PAGE_SIZE); + sg_count = sg_pages_num(count); + + sg_pages = kzalloc_objs(*sg_pages, sg_count); + if (!sg_pages) + return -ENOMEM; + + for (i = 0; i < sg_count; i++) { + sg_pages[i] = alloc_page(GFP_KERNEL); + if (!sg_pages[i]) { + rv = -ENOMEM; + goto out; + } + } + + for (i = 0; i < sg_count; i++) { + efi_capsule_block_desc_t *sglist; + + sglist = kmap_atomic(sg_pages[i]); + + for (j = 0; j < SGLIST_PER_PAGE && count > 0; j++) { + u64 sz = min_t(u64, imagesize, + PAGE_SIZE - (u64)*pages % PAGE_SIZE); + + sglist[j].length = sz; + sglist[j].data = *pages++; + + imagesize -= sz; + count--; + } + + /* Continuation pointer */ + sglist[j].length = 0; + + if (i + 1 == sg_count) + sglist[j].data = 0; + else + sglist[j].data = page_to_phys(sg_pages[i + 1]); + +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) + /* + * At runtime, the firmware has no way to find out where the + * sglist elements are mapped, if they are mapped in the first + * place. Therefore, on architectures that can only perform + * cache maintenance by virtual address, the firmware is unable + * to perform this maintenance, and so it is up to the OS to do + * it instead. + */ + efi_capsule_flush_cache_range(sglist, PAGE_SIZE); +#endif + kunmap_atomic(sglist); + } + + mutex_lock(&capsule_mutex); + rv = efi_capsule_update_locked(capsule, sg_pages, reset_type); + mutex_unlock(&capsule_mutex); + +out: + for (i = 0; rv && i < sg_count; i++) { + if (sg_pages[i]) + __free_page(sg_pages[i]); + } + + kfree(sg_pages); + return rv; +} +EXPORT_SYMBOL_GPL(efi_capsule_update); + +static int capsule_reboot_notify(struct notifier_block *nb, unsigned long event, void *cmd) +{ + mutex_lock(&capsule_mutex); + stop_capsules = true; + mutex_unlock(&capsule_mutex); + + return NOTIFY_DONE; +} + +static struct notifier_block capsule_reboot_nb = { + .notifier_call = capsule_reboot_notify, +}; + +static int __init capsule_reboot_register(void) +{ + return register_reboot_notifier(&capsule_reboot_nb); +} +core_initcall(capsule_reboot_register); |
