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_node {
  17         unsigned char                   type;
  18         int                             refs;
  19
  20         u64 tag;
  21         union {
  22                 unsigned long file_ptr;
  23                 struct io_mapped_ubuf *buf;
  24         };
  25 };
  26
  27 struct io_mapped_ubuf {
  28         u64             ubuf;
  29         unsigned int    len;
  30         unsigned int    nr_bvecs;
  31         unsigned int    folio_shift;
  32         refcount_t      refs;
  33         unsigned long   acct_pages;
  34         struct bio_vec  bvec[] __counted_by(nr_bvecs);
  35 };
  36
  37 struct io_imu_folio_data {
  38         /* Head folio can be partially included in the fixed buf */
  39         unsigned int    nr_pages_head;
  40         /* For non-head/tail folios, has to be fully included */
  41         unsigned int    nr_pages_mid;
  42         unsigned int    folio_shift;
  43 };
  44
  45 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type);
  46 void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node);
  47 void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data);
  48 int io_rsrc_data_alloc(struct io_rsrc_data *data, unsigned nr);
  49
  50 int io_import_fixed(int ddir, struct iov_iter *iter,
  51                            struct io_mapped_ubuf *imu,
  52                            u64 buf_addr, size_t len);
  53
  54 int io_register_clone_buffers(struct io_ring_ctx *ctx, void __user *arg);
  55 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
  56 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
  57                             unsigned int nr_args, u64 __user *tags);
  58 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
  59 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
  60                           unsigned nr_args, u64 __user *tags);
  61
  62 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
  63                              unsigned nr_args);
  64 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
  65                             unsigned size, unsigned type);
  66 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
  67                         unsigned int size, unsigned int type);
  68
  69 static inline struct io_rsrc_node *io_rsrc_node_lookup(struct io_rsrc_data *data,
  70                                                        int index)
  71 {
  72         if (index < data->nr)
  73                 return data->nodes[array_index_nospec(index, data->nr)];
  74         return NULL;
  75 }
  76
  77 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
  78 {
  79         if (node && !--node->refs)
  80                 io_free_rsrc_node(ctx, node);
  81 }
  82
  83 static inline bool io_reset_rsrc_node(struct io_ring_ctx *ctx,
  84                                       struct io_rsrc_data *data, int index)
  85 {
  86         struct io_rsrc_node *node = data->nodes[index];
  87
  88         if (!node)
  89                 return false;
  90         io_put_rsrc_node(ctx, node);
  91         data->nodes[index] = NULL;
  92         return true;
  93 }
  94
  95 static inline void io_req_put_rsrc_nodes(struct io_kiocb *req)
  96 {
  97         if (req->file_node) {
  98                 io_put_rsrc_node(req->ctx, req->file_node);
  99                 req->file_node = NULL;
 100         }
 101         if (req->flags & REQ_F_BUF_NODE) {
 102                 io_put_rsrc_node(req->ctx, req->buf_node);
 103                 req->buf_node = NULL;
 104         }
 105 }
 106
 107 static inline void io_req_assign_rsrc_node(struct io_rsrc_node **dst_node,
 108                                            struct io_rsrc_node *node)
 109 {
 110         node->refs++;
 111         *dst_node = node;
 112 }
 113
 114 static inline void io_req_assign_buf_node(struct io_kiocb *req,
 115                                           struct io_rsrc_node *node)
 116 {
 117         io_req_assign_rsrc_node(&req->buf_node, node);
 118         req->flags |= REQ_F_BUF_NODE;
 119 }
 120
 121 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
 122 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 123
 124 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
 125
 126 static inline void __io_unaccount_mem(struct user_struct *user,
 127                                       unsigned long nr_pages)
 128 {
 129         atomic_long_sub(nr_pages, &user->locked_vm);
 130 }
 131
 132 #endif