tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include <linux/kernel.h>
2#include <linux/gfp.h>
3#include <linux/ide.h>
4#include <linux/jiffies.h>
5#include <linux/blkdev.h>
6
7DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
8
9static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
10{
11 ide_hwif_t *hwif = drive->hwif;
12 struct request_queue *q = drive->queue;
13 struct request *rq;
14 int rc;
15
16 timeout += jiffies;
17 spin_lock_irq(&hwif->lock);
18 if (drive->dev_flags & IDE_DFLAG_PARKED) {
19 int reset_timer = time_before(timeout, drive->sleep);
20 int start_queue = 0;
21
22 drive->sleep = timeout;
23 wake_up_all(&ide_park_wq);
24 if (reset_timer && del_timer(&hwif->timer))
25 start_queue = 1;
26 spin_unlock_irq(&hwif->lock);
27
28 if (start_queue)
29 blk_run_queue(q);
30 return;
31 }
32 spin_unlock_irq(&hwif->lock);
33
34 rq = blk_get_request(q, REQ_OP_DRV_IN, __GFP_RECLAIM);
35 scsi_req_init(rq);
36 scsi_req(rq)->cmd[0] = REQ_PARK_HEADS;
37 scsi_req(rq)->cmd_len = 1;
38 ide_req(rq)->type = ATA_PRIV_MISC;
39 rq->special = &timeout;
40 blk_execute_rq(q, NULL, rq, 1);
41 rc = scsi_req(rq)->result ? -EIO : 0;
42 blk_put_request(rq);
43 if (rc)
44 goto out;
45
46 /*
47 * Make sure that *some* command is sent to the drive after the
48 * timeout has expired, so power management will be reenabled.
49 */
50 rq = blk_get_request(q, REQ_OP_DRV_IN, GFP_NOWAIT);
51 scsi_req_init(rq);
52 if (IS_ERR(rq))
53 goto out;
54
55 scsi_req(rq)->cmd[0] = REQ_UNPARK_HEADS;
56 scsi_req(rq)->cmd_len = 1;
57 ide_req(rq)->type = ATA_PRIV_MISC;
58 elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
59
60out:
61 return;
62}
63
64ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
65{
66 struct ide_cmd cmd;
67 struct ide_taskfile *tf = &cmd.tf;
68
69 memset(&cmd, 0, sizeof(cmd));
70 if (scsi_req(rq)->cmd[0] == REQ_PARK_HEADS) {
71 drive->sleep = *(unsigned long *)rq->special;
72 drive->dev_flags |= IDE_DFLAG_SLEEPING;
73 tf->command = ATA_CMD_IDLEIMMEDIATE;
74 tf->feature = 0x44;
75 tf->lbal = 0x4c;
76 tf->lbam = 0x4e;
77 tf->lbah = 0x55;
78 cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
79 cmd.valid.in.tf = IDE_VALID_IN_TF | IDE_VALID_DEVICE;
80 } else /* cmd == REQ_UNPARK_HEADS */
81 tf->command = ATA_CMD_CHK_POWER;
82
83 cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
84 cmd.protocol = ATA_PROT_NODATA;
85
86 cmd.rq = rq;
87
88 return do_rw_taskfile(drive, &cmd);
89}
90
91ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
92 char *buf)
93{
94 ide_drive_t *drive = to_ide_device(dev);
95 ide_hwif_t *hwif = drive->hwif;
96 unsigned long now;
97 unsigned int msecs;
98
99 if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
100 return -EOPNOTSUPP;
101
102 spin_lock_irq(&hwif->lock);
103 now = jiffies;
104 if (drive->dev_flags & IDE_DFLAG_PARKED &&
105 time_after(drive->sleep, now))
106 msecs = jiffies_to_msecs(drive->sleep - now);
107 else
108 msecs = 0;
109 spin_unlock_irq(&hwif->lock);
110
111 return snprintf(buf, 20, "%u\n", msecs);
112}
113
114ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
115 const char *buf, size_t len)
116{
117#define MAX_PARK_TIMEOUT 30000
118 ide_drive_t *drive = to_ide_device(dev);
119 long int input;
120 int rc;
121
122 rc = kstrtol(buf, 10, &input);
123 if (rc)
124 return rc;
125 if (input < -2)
126 return -EINVAL;
127 if (input > MAX_PARK_TIMEOUT) {
128 input = MAX_PARK_TIMEOUT;
129 rc = -EOVERFLOW;
130 }
131
132 mutex_lock(&ide_setting_mtx);
133 if (input >= 0) {
134 if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
135 rc = -EOPNOTSUPP;
136 else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
137 issue_park_cmd(drive, msecs_to_jiffies(input));
138 } else {
139 if (drive->media == ide_disk)
140 switch (input) {
141 case -1:
142 drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
143 break;
144 case -2:
145 drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
146 break;
147 }
148 else
149 rc = -EOPNOTSUPP;
150 }
151 mutex_unlock(&ide_setting_mtx);
152
153 return rc ? rc : len;
154}