/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_SWIOTLB_H
#define __LINUX_SWIOTLB_H
#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/limits.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
struct device;
struct page;
struct scatterlist;
#define SWIOTLB_VERBOSE (1 << 0) /* verbose initialization */
#define SWIOTLB_FORCE (1 << 1) /* force bounce buffering */
#define SWIOTLB_ANY (1 << 2) /* allow any memory for the buffer */
/*
* Maximum allowable number of contiguous slabs to map,
* must be a power of 2. What is the appropriate value ?
* The complexity of {map,unmap}_single is linearly dependent on this value.
*/
#define IO_TLB_SEGSIZE 128
/*
* log of the size of each IO TLB slab. The number of slabs is command line
* controllable.
*/
#define IO_TLB_SHIFT 11
#define IO_TLB_SIZE (1 << IO_TLB_SHIFT)
/* default to 64MB */
#define IO_TLB_DEFAULT_SIZE (64UL<<20)
unsigned long swiotlb_size_or_default(void);
void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
int (*remap)(void *tlb, unsigned long nslabs));
int swiotlb_init_late(size_t size, gfp_t gfp_mask,
int (*remap)(void *tlb, unsigned long nslabs));
extern void __init swiotlb_update_mem_attributes(void);
#ifdef CONFIG_SWIOTLB
/**
* struct io_tlb_pool - IO TLB memory pool descriptor
* @start: The start address of the swiotlb memory pool. Used to do a quick
* range check to see if the memory was in fact allocated by this
* API.
* @end: The end address of the swiotlb memory pool. Used to do a quick
* range check to see if the memory was in fact allocated by this
* API.
* @vaddr: The vaddr of the swiotlb memory pool. The swiotlb memory pool
* may be remapped in the memory encrypted case and store virtual
* address for bounce buffer operation.
* @nslabs: The number of IO TLB slots between @start and @end. For the
* default swiotlb, this can be adjusted with a boot parameter,
* see setup_io_tlb_npages().
* @late_alloc: %true if allocated using the page allocator.
* @nareas: Number of areas in the pool.
* @area_nslabs: Number of slots in each area.
* @areas: Array of memory area descriptors.
* @slots: Array of slot descriptors.
* @node: Member of the IO TLB memory pool list.
* @rcu: RCU head for swiotlb_dyn_free().
* @transient: %true if transient memory pool.
*/
struct io_tlb_pool {
phys_addr_t start;
phys_addr_t end;
void *vaddr;
unsigned long nslabs;
bool late_alloc;
unsigned int nareas;
unsigned int area_nslabs;
struct io_tlb_area *areas;
struct io_tlb_slot *slots;
#ifdef CONFIG_SWIOTLB_DYNAMIC
struct list_head node;
struct rcu_head rcu;
bool transient;
#endif
};
/**
* struct io_tlb_mem - Software IO TLB allocator
* @defpool: Default (initial) IO TLB memory pool descriptor.
* @pool: IO TLB memory pool descriptor (if not dynamic).
* @nslabs: Total number of IO TLB slabs in all pools.
* @debugfs: The dentry to debugfs.
* @force_bounce: %true if swiotlb bouncing is forced
* @for_alloc: %true if the pool is used for memory allocation
* @can_grow: %true if more pools can be allocated dynamically.
* @phys_limit: Maximum allowed physical address.
* @lock: Lock to synchronize changes to the list.
* @pools: List of IO TLB memory pool descriptors (if dynamic).
* @dyn_alloc: Dynamic IO TLB pool allocation work.
* @total_used: The total number of slots in the pool that are currently used
* across all areas. Used only for calculating used_hiwater in
* debugfs.
* @used_hiwater: The high water mark for total_used. Used only for reporting
* in debugfs.
* @transient_nslabs: The total number of slots in all transient pools that
* are currently used across all areas.
*/
struct io_tlb_mem {
struct io_tlb_pool defpool;
unsigned long nslabs;
struct dentry *debugfs;
bool force_bounce;
bool for_alloc;
#ifdef CONFIG_SWIOTLB_DYNAMIC
bool can_grow;
u64 phys_limit;
spinlock_t lock;
struct list_head pools;
struct work_struct dyn_alloc;
#endif
#ifdef CONFIG_DEBUG_FS
atomic_long_t total_used;
atomic_long_t used_hiwater;
atomic_long_t transient_nslabs;
#endif
};
struct io_tlb_pool *__swiotlb_find_pool(struct device *dev, phys_addr_t paddr);
/**
* swiotlb_find_pool() - find swiotlb pool to which a physical address belongs
* @dev: Device which has mapped the buffer.
* @paddr: Physical address within the DMA buffer.
*
* Find the swiotlb pool that @paddr points into.
*
* Return:
* * pool address if @paddr points into a bounce buffer
* * NULL if @paddr does not point into a bounce buffer. As such, this function
* can be used to determine if @paddr denotes a swiotlb bounce buffer.
*/
static inline struct io_tlb_pool *swiotlb_find_pool(struct device *dev,
phys_addr_t paddr)
{
struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
if (!mem)
return NULL;
#ifdef CONFIG_SWIOTLB_DYNAMIC
/*
* All SWIOTLB buffer addresses must have been returned by
* swiotlb_tbl_map_single() and passed to a device driver.
* If a SWIOTLB address is checked on another CPU, then it was
* presumably loaded by the device driver from an unspecified private
* data structure. Make sure that this load is ordered before reading
* dev->dma_uses_io_tlb here and mem->pools in __swiotlb_find_pool().
*
* This barrier pairs with smp_mb() in swiotlb_find_slots().
*/
smp_rmb();
if (READ_ONCE(dev->dma_uses_io_tlb))
return __swiotlb_find_pool(dev, paddr);
#else
if (paddr >= mem->defpool.start && paddr < mem->defpool.end)
return &mem->defpool;
#endif
return NULL;
}
static inline bool is_swiotlb_force_bounce(struct device *dev)
{
struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
return mem && mem->force_bounce;
}
void swiotlb_init(bool addressing_limited, unsigned int flags);
void __init swiotlb_exit(void);
void swiotlb_dev_init(struct device *dev);
size_t swiotlb_max_mapping_size(struct device *dev);
bool is_swiotlb_allocated(void);
bool is_swiotlb_active(struct device *dev);
void __init swiotlb_adjust_size(unsigned long size);
phys_addr_t default_swiotlb_base(void);
phys_addr_t default_swiotlb_limit(void);
#else
static inline void swiotlb_init(bool addressing_limited, unsigned int flags)
{
}
static inline void swiotlb_dev_init(struct device *dev)
{
}
static inline struct io_tlb_pool *swiotlb_find_pool(struct device *dev,
phys_addr_t paddr)
{
return NULL;
}
static inline bool is_swiotlb_force_bounce(struct device *dev)
{
return false;
}
static inline void swiotlb_exit(void)
{
}
static inline size_t swiotlb_max_mapping_size(struct device *dev)
{
return SIZE_MAX;
}
static inline bool is_swiotlb_allocated(void)
{
return false;
}
static inline bool is_swiotlb_active(struct device *dev)
{
return false;
}
static inline void swiotlb_adjust_size(unsigned long size)
{
}
static inline phys_addr_t default_swiotlb_base(void)
{
return 0;
}
static inline phys_addr_t default_swiotlb_limit(void)
{
return 0;
}
#endif /* CONFIG_SWIOTLB */
phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys,
size_t mapping_size, unsigned int alloc_aligned_mask,
enum dma_data_direction dir, unsigned long attrs);
dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
size_t size, enum dma_data_direction dir, unsigned long attrs);
void __swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
size_t mapping_size, enum dma_data_direction dir,
unsigned long attrs, struct io_tlb_pool *pool);
static inline void swiotlb_tbl_unmap_single(struct device *dev,
phys_addr_t addr, size_t size, enum dma_data_direction dir,
unsigned long attrs)
{
struct io_tlb_pool *pool = swiotlb_find_pool(dev, addr);
if (unlikely(pool))
__swiotlb_tbl_unmap_single(dev, addr, size, dir, attrs, pool);
}
void __swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
size_t size, enum dma_data_direction dir,
struct io_tlb_pool *pool);
static inline void swiotlb_sync_single_for_device(struct device *dev,
phys_addr_t addr, size_t size, enum dma_data_direction dir)
{
struct io_tlb_pool *pool = swiotlb_find_pool(dev, addr);
if (unlikely(pool))
__swiotlb_sync_single_for_device(dev, addr, size, dir, pool);
}
void __swiotlb_sync_single_for_cpu(struct device *dev, phys_addr_t tlb_addr,
size_t size, enum dma_data_direction dir,
struct io_tlb_pool *pool);
static inline void swiotlb_sync_single_for_cpu(struct device *dev,
phys_addr_t addr, size_t size, enum dma_data_direction dir)
{
struct io_tlb_pool *pool = swiotlb_find_pool(dev, addr);
if (unlikely(pool))
__swiotlb_sync_single_for_cpu(dev, addr, size, dir, pool);
}
extern void swiotlb_print_info(void);
#ifdef CONFIG_DMA_RESTRICTED_POOL
struct page *swiotlb_alloc(struct device *dev, size_t size);
bool swiotlb_free(struct device *dev, struct page *page, size_t size);
static inline bool is_swiotlb_for_alloc(struct device *dev)
{
return dev->dma_io_tlb_mem->for_alloc;
}
#else
static inline struct page *swiotlb_alloc(struct device *dev, size_t size)
{
return NULL;
}
static inline bool swiotlb_free(struct device *dev, struct page *page,
size_t size)
{
return false;
}
static inline bool is_swiotlb_for_alloc(struct device *dev)
{
return false;
}
#endif /* CONFIG_DMA_RESTRICTED_POOL */
#endif /* __LINUX_SWIOTLB_H */
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