mirror-linux/drivers/accel/habanalabs/common/hldio.h

147 lines
4.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* hldio.h - NVMe Direct I/O (HLDIO) infrastructure for Habana Labs Driver
*
* This feature requires specific hardware setup and must not be built
* under COMPILE_TEST.
*/
#ifndef __HL_HLDIO_H__
#define __HL_HLDIO_H__
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/ktime.h> /* ktime functions */
#include <linux/delay.h> /* usleep_range */
#include <linux/kernel.h> /* might_sleep_if */
#include <linux/errno.h> /* error codes */
/* Forward declarations */
struct hl_device;
struct file;
/* Enable only if Kconfig selected */
#ifdef CONFIG_HL_HLDIO
/**
* struct hl_p2p_region - describes a single P2P memory region
* @p2ppages: array of page structs for the P2P memory
* @p2pmem: virtual address of the P2P memory region
* @device_pa: physical address on the device
* @bar_offset: offset within the BAR
* @size: size of the region in bytes
* @bar: BAR number containing this region
*/
struct hl_p2p_region {
struct page **p2ppages;
void *p2pmem;
u64 device_pa;
u64 bar_offset;
u64 size;
int bar;
};
/**
* struct hl_dio_stats - Direct I/O statistics
* @total_ops: total number of operations attempted
* @successful_ops: number of successful operations
* @failed_ops: number of failed operations
* @bytes_transferred: total bytes successfully transferred
* @last_len_read: length of the last read operation
*/
struct hl_dio_stats {
u64 total_ops;
u64 successful_ops;
u64 failed_ops;
u64 bytes_transferred;
size_t last_len_read;
};
/**
* struct hl_dio - describes habanalabs direct storage interaction interface
* @p2prs: array of p2p regions
* @inflight_ios: percpu counter for inflight ios
* @np2prs: number of elements in p2prs
* @io_enabled: 1 if io is enabled 0 otherwise
*/
struct hl_dio {
struct hl_p2p_region *p2prs;
s64 __percpu *inflight_ios;
u8 np2prs;
u8 io_enabled;
};
int hl_dio_ssd2hl(struct hl_device *hdev, struct hl_ctx *ctx, int fd,
u64 device_va, off_t off_bytes, size_t len_bytes,
size_t *len_read);
void hl_p2p_region_fini_all(struct hl_device *hdev);
int hl_p2p_region_init(struct hl_device *hdev, struct hl_p2p_region *p2pr);
int hl_dio_start(struct hl_device *hdev);
void hl_dio_stop(struct hl_device *hdev);
/* Init/teardown */
int hl_hldio_init(struct hl_device *hdev);
void hl_hldio_fini(struct hl_device *hdev);
/* File operations */
long hl_hldio_ioctl(struct file *filep, unsigned int cmd, unsigned long arg);
/* DebugFS hooks */
#ifdef CONFIG_DEBUG_FS
void hl_hldio_debugfs_init(struct hl_device *hdev);
void hl_hldio_debugfs_fini(struct hl_device *hdev);
#else
static inline void hl_hldio_debugfs_init(struct hl_device *hdev) { }
static inline void hl_hldio_debugfs_fini(struct hl_device *hdev) { }
#endif
#else /* !CONFIG_HL_HLDIO */
struct hl_p2p_region;
/* Stubs when HLDIO is disabled */
static inline int hl_dio_ssd2hl(struct hl_device *hdev, struct hl_ctx *ctx, int fd,
u64 device_va, off_t off_bytes, size_t len_bytes,
size_t *len_read)
{ return -EOPNOTSUPP; }
static inline void hl_p2p_region_fini_all(struct hl_device *hdev) {}
static inline int hl_p2p_region_init(struct hl_device *hdev, struct hl_p2p_region *p2pr)
{ return -EOPNOTSUPP; }
static inline int hl_dio_start(struct hl_device *hdev) { return -EOPNOTSUPP; }
static inline void hl_dio_stop(struct hl_device *hdev) {}
static inline int hl_hldio_init(struct hl_device *hdev) { return 0; }
static inline void hl_hldio_fini(struct hl_device *hdev) { }
static inline long hl_hldio_ioctl(struct file *f, unsigned int c,
unsigned long a)
{ return -ENOTTY; }
static inline void hl_hldio_debugfs_init(struct hl_device *hdev) { }
static inline void hl_hldio_debugfs_fini(struct hl_device *hdev) { }
#endif /* CONFIG_HL_HLDIO */
/* Simplified polling macro for HLDIO (no simulator support) */
#define hl_poll_timeout_condition(hdev, cond, sleep_us, timeout_us) \
({ \
ktime_t __timeout = ktime_add_us(ktime_get(), timeout_us); \
might_sleep_if(sleep_us); \
(void)(hdev); /* keep signature consistent, hdev unused */ \
for (;;) { \
mb(); /* ensure ordering of memory operations */ \
if (cond) \
break; \
if (timeout_us && ktime_compare(ktime_get(), __timeout) > 0) \
break; \
if (sleep_us) \
usleep_range((sleep_us >> 2) + 1, sleep_us); \
} \
(cond) ? 0 : -ETIMEDOUT; \
})
#ifdef CONFIG_HL_HLDIO
bool hl_device_supports_nvme(struct hl_device *hdev);
#else
static inline bool hl_device_supports_nvme(struct hl_device *hdev) { return false; }
#endif
#endif /* __HL_HLDIO_H__ */