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| 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/misc/sram-exec.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/misc/sram-exec.c')
| -rw-r--r-- | drivers/misc/sram-exec.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/misc/sram-exec.c b/drivers/misc/sram-exec.c new file mode 100644 index 000000000..b71dbbd73 --- /dev/null +++ b/drivers/misc/sram-exec.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SRAM protect-exec region helper functions + * + * Copyright (C) 2017 Texas Instruments Incorporated - https://www.ti.com/ + * Dave Gerlach + */ + +#include <linux/device.h> +#include <linux/genalloc.h> +#include <linux/mm.h> +#include <linux/sram.h> +#include <linux/set_memory.h> + +#include <asm/fncpy.h> + +#include "sram.h" + +static DEFINE_MUTEX(exec_pool_list_mutex); +static LIST_HEAD(exec_pool_list); + +int sram_check_protect_exec(struct sram_dev *sram, struct sram_reserve *block, + struct sram_partition *part) +{ + unsigned long base = (unsigned long)part->base; + unsigned long end = base + block->size; + + if (!PAGE_ALIGNED(base) || !PAGE_ALIGNED(end)) { + dev_err(sram->dev, + "SRAM pool marked with 'protect-exec' is not page aligned and will not be created.\n"); + return -ENOMEM; + } + + return 0; +} + +int sram_add_protect_exec(struct sram_partition *part) +{ + mutex_lock(&exec_pool_list_mutex); + list_add_tail(&part->list, &exec_pool_list); + mutex_unlock(&exec_pool_list_mutex); + + return 0; +} + +/** + * sram_exec_copy - copy data to a protected executable region of sram + * + * @pool: struct gen_pool retrieved that is part of this sram + * @dst: Destination address for the copy, that must be inside pool + * @src: Source address for the data to copy + * @size: Size of copy to perform, which starting from dst, must reside in pool + * + * Return: Address for copied data that can safely be called through function + * pointer, or NULL if problem. + * + * This helper function allows sram driver to act as central control location + * of 'protect-exec' pools which are normal sram pools but are always set + * read-only and executable except when copying data to them, at which point + * they are set to read-write non-executable, to make sure no memory is + * writeable and executable at the same time. This region must be page-aligned + * and is checked during probe, otherwise page attribute manipulation would + * not be possible. Care must be taken to only call the returned address as + * dst address is not guaranteed to be safely callable. + * + * NOTE: This function uses the fncpy macro to move code to the executable + * region. Some architectures have strict requirements for relocating + * executable code, so fncpy is a macro that must be defined by any arch + * making use of this functionality that guarantees a safe copy of exec + * data and returns a safe address that can be called as a C function + * pointer. + */ +void *sram_exec_copy(struct gen_pool *pool, void *dst, void *src, + size_t size) +{ + struct sram_partition *part = NULL, *p; + unsigned long base; + int pages; + void *dst_cpy; + int ret; + + mutex_lock(&exec_pool_list_mutex); + list_for_each_entry(p, &exec_pool_list, list) { + if (p->pool == pool) + part = p; + } + mutex_unlock(&exec_pool_list_mutex); + + if (!part) + return NULL; + + if (!gen_pool_has_addr(pool, (unsigned long)dst, size)) + return NULL; + + base = (unsigned long)part->base; + pages = PAGE_ALIGN(size) / PAGE_SIZE; + + mutex_lock(&part->lock); + + ret = set_memory_nx((unsigned long)base, pages); + if (ret) + goto error_out; + ret = set_memory_rw((unsigned long)base, pages); + if (ret) + goto error_out; + + dst_cpy = fncpy(dst, src, size); + + ret = set_memory_rox((unsigned long)base, pages); + if (ret) + goto error_out; + + mutex_unlock(&part->lock); + + return dst_cpy; + +error_out: + mutex_unlock(&part->lock); + return NULL; +} +EXPORT_SYMBOL_GPL(sram_exec_copy); |
