LXR linux/drivers/usb/host/ohci-mem.c

   1// SPDX-License-Identifier: GPL-1.0+
   2/*
   3 * OHCI HCD (Host Controller Driver) for USB.
   4 *
   5 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
   6 * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
   7 *
   8 * This file is licenced under the GPL.
   9 */
  10
  11/*-------------------------------------------------------------------------*/
  12
  13/*
  14 * OHCI deals with three types of memory:
  15 *      - data used only by the HCD ... kmalloc is fine
  16 *      - async and periodic schedules, shared by HC and HCD ... these
  17 *        need to use dma_pool or dma_alloc_coherent
  18 *      - driver buffers, read/written by HC ... the hcd glue or the
  19 *        device driver provides us with dma addresses
  20 *
  21 * There's also "register" data, which is memory mapped.
  22 * No memory seen by this driver (or any HCD) may be paged out.
  23 */
  24
  25/*-------------------------------------------------------------------------*/
  26
  27static void ohci_hcd_init (struct ohci_hcd *ohci)
  28{
  29        ohci->next_statechange = jiffies;
  30        spin_lock_init (&ohci->lock);
  31        INIT_LIST_HEAD (&ohci->pending);
  32        INIT_LIST_HEAD(&ohci->eds_in_use);
  33}
  34
  35/*-------------------------------------------------------------------------*/
  36
  37static int ohci_mem_init (struct ohci_hcd *ohci)
  38{
  39        ohci->td_cache = dma_pool_create ("ohci_td",
  40                ohci_to_hcd(ohci)->self.controller,
  41                sizeof (struct td),
  42                32 /* byte alignment */,
  43                0 /* no page-crossing issues */);
  44        if (!ohci->td_cache)
  45                return -ENOMEM;
  46        ohci->ed_cache = dma_pool_create ("ohci_ed",
  47                ohci_to_hcd(ohci)->self.controller,
  48                sizeof (struct ed),
  49                16 /* byte alignment */,
  50                0 /* no page-crossing issues */);
  51        if (!ohci->ed_cache) {
  52                dma_pool_destroy (ohci->td_cache);
  53                return -ENOMEM;
  54        }
  55        return 0;
  56}
  57
  58static void ohci_mem_cleanup (struct ohci_hcd *ohci)
  59{
  60        if (ohci->td_cache) {
  61                dma_pool_destroy (ohci->td_cache);
  62                ohci->td_cache = NULL;
  63        }
  64        if (ohci->ed_cache) {
  65                dma_pool_destroy (ohci->ed_cache);
  66                ohci->ed_cache = NULL;
  67        }
  68}
  69
  70/*-------------------------------------------------------------------------*/
  71
  72/* ohci "done list" processing needs this mapping */
  73static inline struct td *
  74dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
  75{
  76        struct td *td;
  77
  78        td_dma &= TD_MASK;
  79        td = hc->td_hash [TD_HASH_FUNC(td_dma)];
  80        while (td && td->td_dma != td_dma)
  81                td = td->td_hash;
  82        return td;
  83}
  84
  85/* TDs ... */
  86static struct td *
  87td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
  88{
  89        dma_addr_t      dma;
  90        struct td       *td;
  91
  92        td = dma_pool_zalloc (hc->td_cache, mem_flags, &dma);
  93        if (td) {
  94                /* in case hc fetches it, make it look dead */
  95                td->hwNextTD = cpu_to_hc32 (hc, dma);
  96                td->td_dma = dma;
  97                /* hashed in td_fill */
  98        }
  99        return td;
 100}
 101
 102static void
 103td_free (struct ohci_hcd *hc, struct td *td)
 104{
 105        struct td       **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
 106
 107        while (*prev && *prev != td)
 108                prev = &(*prev)->td_hash;
 109        if (*prev)
 110                *prev = td->td_hash;
 111        else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
 112                ohci_dbg (hc, "no hash for td %p\n", td);
 113        dma_pool_free (hc->td_cache, td, td->td_dma);
 114}
 115
 116/*-------------------------------------------------------------------------*/
 117
 118/* EDs ... */
 119static struct ed *
 120ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
 121{
 122        dma_addr_t      dma;
 123        struct ed       *ed;
 124
 125        ed = dma_pool_zalloc (hc->ed_cache, mem_flags, &dma);
 126        if (ed) {
 127                INIT_LIST_HEAD (&ed->td_list);
 128                ed->dma = dma;
 129        }
 130        return ed;
 131}
 132
 133static void
 134ed_free (struct ohci_hcd *hc, struct ed *ed)
 135{
 136        dma_pool_free (hc->ed_cache, ed, ed->dma);
 137}
 138
 139