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 struct io_rsrc_data {
  26         struct io_ring_ctx              *ctx;
  27
  28         u64                             **tags;
  29         unsigned int                    nr;
  30         u16                             rsrc_type;
  31         bool                            quiesce;
  32 };
  33
  34 struct io_rsrc_node {
  35         struct io_ring_ctx              *ctx;
  36         int                             refs;
  37         bool                            empty;
  38         u16                             type;
  39         struct list_head                node;
  40         struct io_rsrc_put              item;
  41 };
  42
  43 struct io_mapped_ubuf {
  44         u64             ubuf;
  45         unsigned int    len;
  46         unsigned int    nr_bvecs;
  47         unsigned int    folio_shift;
  48         refcount_t      refs;
  49         unsigned long   acct_pages;
  50         struct bio_vec  bvec[] __counted_by(nr_bvecs);
  51 };
  52
  53 struct io_imu_folio_data {
  54         /* Head folio can be partially included in the fixed buf */
  55         unsigned int    nr_pages_head;
  56         /* For non-head/tail folios, has to be fully included */
  57         unsigned int    nr_pages_mid;
  58         unsigned int    folio_shift;
  59 };
  60
  61 void io_rsrc_node_ref_zero(struct io_rsrc_node *node);
  62 void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *ref_node);
  63 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx);
  64 int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, void *rsrc);
  65
  66 int io_import_fixed(int ddir, struct iov_iter *iter,
  67                            struct io_mapped_ubuf *imu,
  68                            u64 buf_addr, size_t len);
  69
  70 int io_register_clone_buffers(struct io_ring_ctx *ctx, void __user *arg);
  71 void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
  72 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
  73 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
  74                             unsigned int nr_args, u64 __user *tags);
  75 void __io_sqe_files_unregister(struct io_ring_ctx *ctx);
  76 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
  77 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
  78                           unsigned nr_args, u64 __user *tags);
  79
  80 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
  81                              unsigned nr_args);
  82 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
  83                             unsigned size, unsigned type);
  84 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
  85                         unsigned int size, unsigned int type);
  86
  87 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
  88 {
  89         lockdep_assert_held(&ctx->uring_lock);
  90
  91         if (node && !--node->refs)
  92                 io_rsrc_node_ref_zero(node);
  93 }
  94
  95 static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx,
  96                                        struct io_rsrc_node *node)
  97 {
  98         node->refs++;
  99 }
 100
 101 static inline void __io_req_set_rsrc_node(struct io_kiocb *req,
 102                                           struct io_ring_ctx *ctx)
 103 {
 104         lockdep_assert_held(&ctx->uring_lock);
 105         req->rsrc_node = ctx->rsrc_node;
 106         io_charge_rsrc_node(ctx, ctx->rsrc_node);
 107 }
 108
 109 static inline void io_req_set_rsrc_node(struct io_kiocb *req,
 110                                         struct io_ring_ctx *ctx,
 111                                         unsigned int issue_flags)
 112 {
 113         if (!req->rsrc_node) {
 114                 io_ring_submit_lock(ctx, issue_flags);
 115                 __io_req_set_rsrc_node(req, ctx);
 116                 io_ring_submit_unlock(ctx, issue_flags);
 117         }
 118 }
 119
 120 static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
 121 {
 122         unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
 123         unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
 124
 125         return &data->tags[table_idx][off];
 126 }
 127
 128 static inline int io_rsrc_init(struct io_ring_ctx *ctx)
 129 {
 130         ctx->rsrc_node = io_rsrc_node_alloc(ctx);
 131         return ctx->rsrc_node ? 0 : -ENOMEM;
 132 }
 133
 134 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
 135 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 136
 137 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
 138
 139 static inline void __io_unaccount_mem(struct user_struct *user,
 140                                       unsigned long nr_pages)
 141 {
 142         atomic_long_sub(nr_pages, &user->locked_vm);
 143 }
 144
 145 #endif