1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (c) 2006, Intel Corporation.
4 *
5 * Copyright (C) 2006-2008 Intel Corporation
6 * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
7 */
8
9#ifndef _IOVA_H_
10#define _IOVA_H_
11
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/rbtree.h>
15#include <linux/atomic.h>
16#include <linux/dma-mapping.h>
17
18/* iova structure */
19struct iova {
20    struct rb_node node;
21    unsigned long pfn_hi; /* Highest allocated pfn */
22    unsigned long pfn_lo; /* Lowest allocated pfn */
23};
24
25struct iova_magazine;
26struct iova_cpu_rcache;
27
28#define IOVA_RANGE_CACHE_MAX_SIZE 6 /* log of max cached IOVA range size (in pages) */
29#define MAX_GLOBAL_MAGS 32          /* magazines per bin */
30
31struct iova_rcache {
32    spinlock_t lock;
33    unsigned long depot_size;
34    struct iova_magazine *depot[MAX_GLOBAL_MAGS];
35    struct iova_cpu_rcache __percpu *cpu_rcaches;
36};
37
38struct iova_domain;
39
40/* Call-Back from IOVA code into IOMMU drivers */
41typedef void (*iova_flush_cb)(struct iova_domain *domain);
42
43/* Destructor for per-entry data */
44typedef void (*iova_entry_dtor)(unsigned long data);
45
46/* Number of entries per Flush Queue */
47#define IOVA_FQ_SIZE 256
48
49/* Timeout (in ms) after which entries are flushed from the Flush-Queue */
50#define IOVA_FQ_TIMEOUT 10
51
52/* Flush Queue entry for defered flushing */
53struct iova_fq_entry {
54    unsigned long iova_pfn;
55    unsigned long pages;
56    unsigned long data;
57    u64 counter; /* Flush counter when this entrie was added */
58};
59
60/* Per-CPU Flush Queue structure */
61struct iova_fq {
62    struct iova_fq_entry entries[IOVA_FQ_SIZE];
63    unsigned head, tail;
64    spinlock_t lock;
65};
66
67/* holds all the iova translations for a domain */
68struct iova_domain {
69    spinlock_t iova_rbtree_lock;   /* Lock to protect update of rbtree */
70    struct rb_root rbroot;         /* iova domain rbtree root */
71    struct rb_node *cached_node;   /* Save last alloced node */
72    struct rb_node *cached32_node; /* Save last 32-bit alloced node */
73    unsigned long granule;         /* pfn granularity for this domain */
74    unsigned long start_pfn;       /* Lower limit for this domain */
75    unsigned long dma_32bit_pfn;
76    unsigned long max32_alloc_size; /* Size of last failed allocation */
77    struct iova_fq __percpu *fq;    /* Flush Queue */
78
79    atomic64_t fq_flush_start_cnt; /* Number of TLB flushes that
80                     have been started */
81
82    atomic64_t fq_flush_finish_cnt; /* Number of TLB flushes that
83                     have been finished */
84
85    struct iova anchor;                                    /* rbtree lookup anchor */
86    struct iova_rcache rcaches[IOVA_RANGE_CACHE_MAX_SIZE]; /* IOVA range caches */
87
88    iova_flush_cb flush_cb; /* Call-Back function to flush IOMMU
89                 TLBs */
90
91    iova_entry_dtor entry_dtor; /* IOMMU driver specific destructor for
92                    iova entry */
93
94    struct timer_list fq_timer; /* Timer to regularily empty the
95                    flush-queues */
96    atomic_t fq_timer_on;       /* 1 when timer is active, 0
97                      when not */
98    bool best_fit;
99};
100
101static inline unsigned long iova_size(struct iova *iova)
102{
103    return iova->pfn_hi - iova->pfn_lo + 1;
104}
105
106static inline unsigned long iova_shift(struct iova_domain *iovad)
107{
108    return __ffs(iovad->granule);
109}
110
111static inline unsigned long iova_mask(struct iova_domain *iovad)
112{
113    return iovad->granule - 1;
114}
115
116static inline size_t iova_offset(struct iova_domain *iovad, dma_addr_t iova)
117{
118    return iova & iova_mask(iovad);
119}
120
121static inline size_t iova_align(struct iova_domain *iovad, size_t size)
122{
123    return ALIGN(size, iovad->granule);
124}
125
126static inline dma_addr_t iova_dma_addr(struct iova_domain *iovad, struct iova *iova)
127{
128    return (dma_addr_t)iova->pfn_lo << iova_shift(iovad);
129}
130
131static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
132{
133    return iova >> iova_shift(iovad);
134}
135
136#if IS_ENABLED(CONFIG_IOMMU_IOVA)
137int iova_cache_get(void);
138void iova_cache_put(void);
139
140struct iova *alloc_iova_mem(void);
141void free_iova_mem(struct iova *iova);
142void free_iova(struct iova_domain *iovad, unsigned long pfn);
143void __free_iova(struct iova_domain *iovad, struct iova *iova);
144struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size, unsigned long limit_pfn, bool size_aligned);
145void free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size);
146void queue_iova(struct iova_domain *iovad, unsigned long pfn, unsigned long pages, unsigned long data);
147unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size, unsigned long limit_pfn,
148                              bool flush_rcache);
149struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo, unsigned long pfn_hi);
150void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
151void init_iova_domain(struct iova_domain *iovad, unsigned long granule, unsigned long start_pfn);
152bool has_iova_flush_queue(struct iova_domain *iovad);
153int init_iova_flush_queue(struct iova_domain *iovad, iova_flush_cb flush_cb, iova_entry_dtor entry_dtor);
154struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
155void put_iova_domain(struct iova_domain *iovad);
156struct iova *split_and_remove_iova(struct iova_domain *iovad, struct iova *iova, unsigned long pfn_lo,
157                                   unsigned long pfn_hi);
158void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad);
159#else
160static inline int iova_cache_get(void)
161{
162    return -ENOTSUPP;
163}
164
165static inline void iova_cache_put(void)
166{
167}
168
169static inline struct iova *alloc_iova_mem(void)
170{
171    return NULL;
172}
173
174static inline void free_iova_mem(struct iova *iova)
175{
176}
177
178static inline void free_iova(struct iova_domain *iovad, unsigned long pfn)
179{
180}
181
182static inline void __free_iova(struct iova_domain *iovad, struct iova *iova)
183{
184}
185
186static inline struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size, unsigned long limit_pfn,
187                                      bool size_aligned)
188{
189    return NULL;
190}
191
192static inline void free_iova_fast(struct iova_domain *iovad, unsigned long pfn, unsigned long size)
193{
194}
195
196static inline void queue_iova(struct iova_domain *iovad, unsigned long pfn, unsigned long pages, unsigned long data)
197{
198}
199
200static inline unsigned long alloc_iova_fast(struct iova_domain *iovad, unsigned long size, unsigned long limit_pfn,
201                                            bool flush_rcache)
202{
203    return 0;
204}
205
206static inline struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo, unsigned long pfn_hi)
207{
208    return NULL;
209}
210
211static inline void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
212{
213}
214
215static inline void init_iova_domain(struct iova_domain *iovad, unsigned long granule, unsigned long start_pfn)
216{
217}
218
219static inline bool has_iova_flush_queue(struct iova_domain *iovad)
220{
221    return false;
222}
223
224static inline int init_iova_flush_queue(struct iova_domain *iovad, iova_flush_cb flush_cb, iova_entry_dtor entry_dtor)
225{
226    return -ENODEV;
227}
228
229static inline struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
230{
231    return NULL;
232}
233
234static inline void put_iova_domain(struct iova_domain *iovad)
235{
236}
237
238static inline struct iova *split_and_remove_iova(struct iova_domain *iovad, struct iova *iova, unsigned long pfn_lo,
239                                                 unsigned long pfn_hi)
240{
241    return NULL;
242}
243
244static inline void free_cpu_cached_iovas(unsigned int cpu, struct iova_domain *iovad)
245{
246}
247#endif
248
249#endif
250