xref: /openbmc/linux/drivers/scsi/elx/libefc/efclib.c (revision 99a15348)
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 }
82