io_uring/rsrc.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 #ifndef IOU_RSRC_H
   3 #define IOU_RSRC_H
   4
   5 #define IO_NODE_ALLOC_CACHE_MAX 32
   6
   7 #define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3)
   8 #define IO_RSRC_TAG_TABLE_MAX   (1U << IO_RSRC_TAG_TABLE_SHIFT)
   9 #define IO_RSRC_TAG_TABLE_MASK  (IO_RSRC_TAG_TABLE_MAX - 1)
  10
  11 enum {
  12         IORING_RSRC_FILE                = 0,
  13         IORING_RSRC_BUFFER              = 1,
  14 };
  15
  16 struct io_rsrc_put {
  17         u64 tag;
  18         union {
  19                 void *rsrc;
  20                 struct file *file;
  21                 struct io_mapped_ubuf *buf;
  22         };
  23 };
  24
  25 typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
  26
  27 struct io_rsrc_data {
  28         struct io_ring_ctx              *ctx;
  29
  30         u64                             **tags;
  31         unsigned int                    nr;
  32         u16                             rsrc_type;
  33         bool                            quiesce;
  34 };
  35
  36 struct io_rsrc_node {
  37         struct io_ring_ctx              *ctx;
  38         int                             refs;
  39         bool                            empty;
  40         u16                             type;
  41         struct list_head                node;
  42         struct io_rsrc_put              item;
  43 };
  44
  45 struct io_mapped_ubuf {
  46         u64             ubuf;
  47         u64             ubuf_end;
  48         unsigned int    nr_bvecs;
  49         unsigned long   acct_pages;
  50         struct bio_vec  bvec[] __counted_by(nr_bvecs);
  51 };
  52
  53 void io_rsrc_node_ref_zero(struct io_rsrc_node *node);
  54 void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *ref_node);
  55 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx);
  56 int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, void *rsrc);
  57
  58 int io_import_fixed(int ddir, struct iov_iter *iter,
  59                            struct io_mapped_ubuf *imu,
  60                            u64 buf_addr, size_t len);
  61
  62 void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
  63 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
  64 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
  65                             unsigned int nr_args, u64 __user *tags);
  66 void __io_sqe_files_unregister(struct io_ring_ctx *ctx);
  67 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
  68 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
  69                           unsigned nr_args, u64 __user *tags);
  70
  71 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
  72                              unsigned nr_args);
  73 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
  74                             unsigned size, unsigned type);
  75 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
  76                         unsigned int size, unsigned int type);
  77
  78 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
  79 {
  80         lockdep_assert_held(&ctx->uring_lock);
  81
  82         if (node && !--node->refs)
  83                 io_rsrc_node_ref_zero(node);
  84 }
  85
  86 static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx,
  87                                        struct io_rsrc_node *node)
  88 {
  89         node->refs++;
  90 }
  91
  92 static inline void __io_req_set_rsrc_node(struct io_kiocb *req,
  93                                           struct io_ring_ctx *ctx)
  94 {
  95         lockdep_assert_held(&ctx->uring_lock);
  96         req->rsrc_node = ctx->rsrc_node;
  97         io_charge_rsrc_node(ctx, ctx->rsrc_node);
  98 }
  99
 100 static inline void io_req_set_rsrc_node(struct io_kiocb *req,
 101                                         struct io_ring_ctx *ctx,
 102                                         unsigned int issue_flags)
 103 {
 104         if (!req->rsrc_node) {
 105                 io_ring_submit_lock(ctx, issue_flags);
 106                 __io_req_set_rsrc_node(req, ctx);
 107                 io_ring_submit_unlock(ctx, issue_flags);
 108         }
 109 }
 110
 111 static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
 112 {
 113         unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
 114         unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
 115
 116         return &data->tags[table_idx][off];
 117 }
 118
 119 static inline int io_rsrc_init(struct io_ring_ctx *ctx)
 120 {
 121         ctx->rsrc_node = io_rsrc_node_alloc(ctx);
 122         return ctx->rsrc_node ? 0 : -ENOMEM;
 123 }
 124
 125 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
 126 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 127
 128 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
 129
 130 static inline void __io_unaccount_mem(struct user_struct *user,
 131                                       unsigned long nr_pages)
 132 {
 133         atomic_long_sub(nr_pages, &user->locked_vm);
 134 }
 135
 136 #endif