Files
ack-tegra/drivers/iommu/io-pgtable.c
Jean-Philippe Brucker efe0081240 BACKPORT: FROMLIST: iommu/io-pgtable: Add configure() operation
Allow IOMMU drivers to create the io-pgtable configuration without
allocating any tables. This will be used by the SMMUv3-KVM driver to
initialize a config and pass it to KVM.

Link: https://lore.kernel.org/all/20241212180423.1578358-4-smostafa@google.com/

Bug: 357781595
Bug: 384432312

Change-Id: I6e6aed0f7e2c57d07bd15519569a886d07330e60
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Mostafa Saleh <smostafa@google.com>
2024-12-20 03:25:14 -08:00

117 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Generic page table allocator for IOMMUs.
*
* Copyright (C) 2014 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/bug.h>
#include <linux/io-pgtable.h>
#include <linux/kernel.h>
#include <linux/types.h>
static const struct io_pgtable_init_fns *
io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE
[ARM_32_LPAE_S1] = &io_pgtable_arm_32_lpae_s1_init_fns,
[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
[ARM_MALI_LPAE] = &io_pgtable_arm_mali_lpae_init_fns,
#endif
#ifdef CONFIG_IOMMU_IO_PGTABLE_DART
[APPLE_DART] = &io_pgtable_apple_dart_init_fns,
[APPLE_DART2] = &io_pgtable_apple_dart_init_fns,
#endif
#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
#endif
#ifdef CONFIG_AMD_IOMMU
[AMD_IOMMU_V1] = &io_pgtable_amd_iommu_v1_init_fns,
[AMD_IOMMU_V2] = &io_pgtable_amd_iommu_v2_init_fns,
#endif
};
static int check_custom_allocator(enum io_pgtable_fmt fmt,
struct io_pgtable_cfg *cfg)
{
/* No custom allocator, no need to check the format. */
if (!cfg->alloc && !cfg->free)
return 0;
/* When passing a custom allocator, both the alloc and free
* functions should be provided.
*/
if (!cfg->alloc || !cfg->free)
return -EINVAL;
/* Make sure the format supports custom allocators. */
if (io_pgtable_init_table[fmt]->caps & IO_PGTABLE_CAP_CUSTOM_ALLOCATOR)
return 0;
return -EINVAL;
}
struct io_pgtable_ops *alloc_io_pgtable_ops(enum io_pgtable_fmt fmt,
struct io_pgtable_cfg *cfg,
void *cookie)
{
struct io_pgtable *iop;
const struct io_pgtable_init_fns *fns;
if (fmt >= IO_PGTABLE_NUM_FMTS)
return NULL;
if (check_custom_allocator(fmt, cfg))
return NULL;
fns = io_pgtable_init_table[fmt];
if (!fns)
return NULL;
iop = fns->alloc(cfg, cookie);
if (!iop)
return NULL;
iop->fmt = fmt;
iop->cookie = cookie;
iop->cfg = *cfg;
return &iop->ops;
}
EXPORT_SYMBOL_GPL(alloc_io_pgtable_ops);
/*
* It is the IOMMU driver's responsibility to ensure that the page table
* is no longer accessible to the walker by this point.
*/
void free_io_pgtable_ops(struct io_pgtable_ops *ops)
{
struct io_pgtable *iop;
if (!ops)
return;
iop = io_pgtable_ops_to_pgtable(ops);
io_pgtable_tlb_flush_all(iop);
io_pgtable_init_table[iop->fmt]->free(iop);
}
EXPORT_SYMBOL_GPL(free_io_pgtable_ops);
int io_pgtable_configure(struct io_pgtable_cfg *cfg)
{
const struct io_pgtable_init_fns *fns;
if (cfg->fmt >= IO_PGTABLE_NUM_FMTS)
return -EINVAL;
fns = io_pgtable_init_table[cfg->fmt];
if (!fns || !fns->configure)
return -EOPNOTSUPP;
return fns->configure(cfg);
}
EXPORT_SYMBOL_GPL(io_pgtable_configure);