drivers/scsi/elx/libefc/efclib.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2021 Broadcom. All Rights Reserved. The term
   4  * “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.
   5  */
   6
   7 /*
   8  * LIBEFC LOCKING
   9  *
  10  * The critical sections protected by the efc's spinlock are quite broad and
  11  * may be improved upon in the future. The libefc code and its locking doesn't
  12  * influence the I/O path, so excessive locking doesn't impact I/O performance.
  13  *
  14  * The strategy is to lock whenever processing a request from user driver. This
  15  * means that the entry points into the libefc library are protected by efc
  16  * lock. So all the state machine transitions are protected.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/kernel.h>
  21 #include "efc.h"
  22
  23 int efcport_init(struct efc *efc)
  24 {
  25         u32 rc = 0;
  26
  27         spin_lock_init(&efc->lock);
  28         INIT_LIST_HEAD(&efc->vport_list);
  29         efc->hold_frames = false;
  30         spin_lock_init(&efc->pend_frames_lock);
  31         INIT_LIST_HEAD(&efc->pend_frames);
  32
  33         /* Create Node pool */
  34         efc->node_pool = mempool_create_kmalloc_pool(EFC_MAX_REMOTE_NODES,
  35                                                      sizeof(struct efc_node));
  36         if (!efc->node_pool) {
  37                 efc_log_err(efc, "Can't allocate node pool\n");
  38                 return -ENOMEM;
  39         }
  40
  41         efc->node_dma_pool = dma_pool_create("node_dma_pool", &efc->pci->dev,
  42                                              NODE_SPARAMS_SIZE, 0, 0);
  43         if (!efc->node_dma_pool) {
  44                 efc_log_err(efc, "Can't allocate node dma pool\n");
  45                 mempool_destroy(efc->node_pool);
  46                 return -ENOMEM;
  47         }
  48
  49         efc->els_io_pool = mempool_create_kmalloc_pool(EFC_ELS_IO_POOL_SZ,
  50                                                 sizeof(struct efc_els_io_req));
  51         if (!efc->els_io_pool) {
  52                 efc_log_err(efc, "Can't allocate els io pool\n");
  53                 return -ENOMEM;
  54         }
  55
  56         return rc;
  57 }
  58
  59 static void
  60 efc_purge_pending(struct efc *efc)
  61 {
  62         struct efc_hw_sequence *frame, *next;
  63         unsigned long flags = 0;
  64
  65         spin_lock_irqsave(&efc->pend_frames_lock, flags);
  66
  67         list_for_each_entry_safe(frame, next, &efc->pend_frames, list_entry) {
  68                 list_del(&frame->list_entry);
  69                 efc->tt.hw_seq_free(efc, frame);
  70         }
  71
  72         spin_unlock_irqrestore(&efc->pend_frames_lock, flags);
  73 }
  74
  75 void efcport_destroy(struct efc *efc)
  76 {
  77         efc_purge_pending(efc);
  78         mempool_destroy(efc->els_io_pool);
  79         mempool_destroy(efc->node_pool);
  80         dma_pool_destroy(efc->node_dma_pool);
  81 }