1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * hldio.h - NVMe Direct I/O (HLDIO) infrastructure for Habana Labs Driver 4 * 5 * This feature requires specific hardware setup and must not be built 6 * under COMPILE_TEST. 7 */ 8 9 #ifndef __HL_HLDIO_H__ 10 #define __HL_HLDIO_H__ 11 12 #include <linux/types.h> 13 #include <linux/fs.h> 14 #include <linux/seq_file.h> 15 #include <linux/ktime.h> /* ktime functions */ 16 #include <linux/delay.h> /* usleep_range */ 17 #include <linux/kernel.h> /* might_sleep_if */ 18 #include <linux/errno.h> /* error codes */ 19 20 /* Forward declarations */ 21 struct hl_device; 22 struct file; 23 24 /* Enable only if Kconfig selected */ 25 #ifdef CONFIG_HL_HLDIO 26 /** 27 * struct hl_p2p_region - describes a single P2P memory region 28 * @p2ppages: array of page structs for the P2P memory 29 * @p2pmem: virtual address of the P2P memory region 30 * @device_pa: physical address on the device 31 * @bar_offset: offset within the BAR 32 * @size: size of the region in bytes 33 * @bar: BAR number containing this region 34 */ 35 struct hl_p2p_region { 36 struct page **p2ppages; 37 void *p2pmem; 38 u64 device_pa; 39 u64 bar_offset; 40 u64 size; 41 int bar; 42 }; 43 44 /** 45 * struct hl_dio_stats - Direct I/O statistics 46 * @total_ops: total number of operations attempted 47 * @successful_ops: number of successful operations 48 * @failed_ops: number of failed operations 49 * @bytes_transferred: total bytes successfully transferred 50 * @last_len_read: length of the last read operation 51 */ 52 struct hl_dio_stats { 53 u64 total_ops; 54 u64 successful_ops; 55 u64 failed_ops; 56 u64 bytes_transferred; 57 size_t last_len_read; 58 }; 59 60 /** 61 * struct hl_dio - describes habanalabs direct storage interaction interface 62 * @p2prs: array of p2p regions 63 * @inflight_ios: percpu counter for inflight ios 64 * @np2prs: number of elements in p2prs 65 * @io_enabled: 1 if io is enabled 0 otherwise 66 */ 67 struct hl_dio { 68 struct hl_p2p_region *p2prs; 69 s64 __percpu *inflight_ios; 70 u8 np2prs; 71 u8 io_enabled; 72 }; 73 74 int hl_dio_ssd2hl(struct hl_device *hdev, struct hl_ctx *ctx, int fd, 75 u64 device_va, off_t off_bytes, size_t len_bytes, 76 size_t *len_read); 77 void hl_p2p_region_fini_all(struct hl_device *hdev); 78 int hl_p2p_region_init(struct hl_device *hdev, struct hl_p2p_region *p2pr); 79 int hl_dio_start(struct hl_device *hdev); 80 void hl_dio_stop(struct hl_device *hdev); 81 82 /* Init/teardown */ 83 int hl_hldio_init(struct hl_device *hdev); 84 void hl_hldio_fini(struct hl_device *hdev); 85 86 /* File operations */ 87 long hl_hldio_ioctl(struct file *filep, unsigned int cmd, unsigned long arg); 88 89 /* DebugFS hooks */ 90 #ifdef CONFIG_DEBUG_FS 91 void hl_hldio_debugfs_init(struct hl_device *hdev); 92 void hl_hldio_debugfs_fini(struct hl_device *hdev); 93 #else 94 static inline void hl_hldio_debugfs_init(struct hl_device *hdev) { } 95 static inline void hl_hldio_debugfs_fini(struct hl_device *hdev) { } 96 #endif 97 98 #else /* !CONFIG_HL_HLDIO */ 99 100 struct hl_p2p_region; 101 /* Stubs when HLDIO is disabled */ 102 static inline int hl_dio_ssd2hl(struct hl_device *hdev, struct hl_ctx *ctx, int fd, 103 u64 device_va, off_t off_bytes, size_t len_bytes, 104 size_t *len_read) 105 { return -EOPNOTSUPP; } 106 static inline void hl_p2p_region_fini_all(struct hl_device *hdev) {} 107 static inline int hl_p2p_region_init(struct hl_device *hdev, struct hl_p2p_region *p2pr) 108 { return -EOPNOTSUPP; } 109 static inline int hl_dio_start(struct hl_device *hdev) { return -EOPNOTSUPP; } 110 static inline void hl_dio_stop(struct hl_device *hdev) {} 111 112 static inline int hl_hldio_init(struct hl_device *hdev) { return 0; } 113 static inline void hl_hldio_fini(struct hl_device *hdev) { } 114 static inline long hl_hldio_ioctl(struct file *f, unsigned int c, 115 unsigned long a) 116 { return -ENOTTY; } 117 static inline void hl_hldio_debugfs_init(struct hl_device *hdev) { } 118 static inline void hl_hldio_debugfs_fini(struct hl_device *hdev) { } 119 120 #endif /* CONFIG_HL_HLDIO */ 121 122 /* Simplified polling macro for HLDIO (no simulator support) */ 123 #define hl_poll_timeout_condition(hdev, cond, sleep_us, timeout_us) \ 124 ({ \ 125 ktime_t __timeout = ktime_add_us(ktime_get(), timeout_us); \ 126 might_sleep_if(sleep_us); \ 127 (void)(hdev); /* keep signature consistent, hdev unused */ \ 128 for (;;) { \ 129 mb(); /* ensure ordering of memory operations */ \ 130 if (cond) \ 131 break; \ 132 if (timeout_us && ktime_compare(ktime_get(), __timeout) > 0) \ 133 break; \ 134 if (sleep_us) \ 135 usleep_range((sleep_us >> 2) + 1, sleep_us); \ 136 } \ 137 (cond) ? 0 : -ETIMEDOUT; \ 138 }) 139 140 #ifdef CONFIG_HL_HLDIO 141 bool hl_device_supports_nvme(struct hl_device *hdev); 142 #else 143 static inline bool hl_device_supports_nvme(struct hl_device *hdev) { return false; } 144 #endif 145 146 #endif /* __HL_HLDIO_H__ */ 147