/**
* match_dev_by_uuid - callback for finding a partition using its uuid
* @dev: device passed in by the caller
* @data: opaque pointer to a 36 byte char array with a UUID
*
* Returns 1 if the device matches, and 0 otherwise.
*/
static int match_dev_by_uuid(struct device *dev, void *data)
{
u8 *uuid = data;
struct hd_struct *part = dev_to_part(dev);
if (!part->info)
goto no_match;
if (memcmp(uuid, part->info->uuid, sizeof(part->info->uuid)))
goto no_match;
return 1;
no_match:
return 0;
}
/**
* match_dev_by_uuid - callback for finding a partition using its uuid
* @dev: device passed in by the caller
* @data: opaque pointer to the desired struct uuidcmp to match
*
* Returns 1 if the device matches, and 0 otherwise.
*/
static int match_dev_by_uuid(struct device *dev, const void *data)
{
const struct uuidcmp *cmp = data;
struct hd_struct *part = dev_to_part(dev);
if (!part->info)
goto no_match;
if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
goto no_match;
return 1;
no_match:
return 0;
}
static int sony_ric_bdev_mount(const char *dev_name, struct path *path,
struct inode *inode, unsigned long flags)
{
struct device *dev;
struct hd_struct *part;
int ret = 0;
dev = class_find_device(&block_class, NULL, &inode->i_rdev,
&match_device_by_devt);
if (!dev)
return ret;
part = dev_to_part(dev);
if (!part->info) {
pr_debug("RIC: No partition info for %s\n", dev_name);
goto done;
}
ret = sony_ric_bdev_mount_perm(part->info->volname, path, flags);
done:
put_device(dev);
return ret;
}
static int blk_trace_synthesize_old_trace(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
struct blk_io_trace *t = (struct blk_io_trace *)iter->ent;
const int offset = offsetof(struct blk_io_trace, sector);
struct blk_io_trace old = {
.magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION,
.time = iter->ts,
};
if (!trace_seq_putmem(s, &old, offset))
return 0;
return trace_seq_putmem(s, &t->sector,
sizeof(old) - offset + t->pdu_len);
}
static enum print_line_t
blk_trace_event_print_binary(struct trace_iterator *iter, int flags)
{
return blk_trace_synthesize_old_trace(iter) ?
TRACE_TYPE_HANDLED : TRACE_TYPE_PARTIAL_LINE;
}
static enum print_line_t blk_tracer_print_line(struct trace_iterator *iter)
{
if (!(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC))
return TRACE_TYPE_UNHANDLED;
return print_one_line(iter, true);
}
static int blk_tracer_set_flag(u32 old_flags, u32 bit, int set)
{
/* don't output context-info for blk_classic output */
if (bit == TRACE_BLK_OPT_CLASSIC) {
if (set)
trace_flags &= ~TRACE_ITER_CONTEXT_INFO;
else
trace_flags |= TRACE_ITER_CONTEXT_INFO;
}
return 0;
}
static struct tracer blk_tracer __read_mostly = {
.name = "blk",
.init = blk_tracer_init,
.reset = blk_tracer_reset,
.start = blk_tracer_start,
.stop = blk_tracer_stop,
.print_header = blk_tracer_print_header,
.print_line = blk_tracer_print_line,
.flags = &blk_tracer_flags,
.set_flag = blk_tracer_set_flag,
};
static struct trace_event trace_blk_event = {
.type = TRACE_BLK,
.trace = blk_trace_event_print,
.binary = blk_trace_event_print_binary,
};
static int __init init_blk_tracer(void)
{
if (!register_ftrace_event(&trace_blk_event)) {
pr_warning("Warning: could not register block events\n");
return 1;
}
if (register_tracer(&blk_tracer) != 0) {
pr_warning("Warning: could not register the block tracer\n");
unregister_ftrace_event(&trace_blk_event);
return 1;
}
return 0;
}
device_initcall(init_blk_tracer);
static int blk_trace_remove_queue(struct request_queue *q)
{
struct blk_trace *bt;
bt = xchg(&q->blk_trace, NULL);
if (bt == NULL)
return -EINVAL;
if (atomic_dec_and_test(&blk_probes_ref))
blk_unregister_tracepoints();
blk_trace_free(bt);
return 0;
}
/*
* Setup everything required to start tracing
*/
static int blk_trace_setup_queue(struct request_queue *q,
struct block_device *bdev)
{
struct blk_trace *old_bt, *bt = NULL;
int ret = -ENOMEM;
bt = kzalloc(sizeof(*bt), GFP_KERNEL);
if (!bt)
return -ENOMEM;
bt->msg_data = __alloc_percpu(BLK_TN_MAX_MSG, __alignof__(char));
if (!bt->msg_data)
goto free_bt;
bt->dev = bdev->bd_dev;
bt->act_mask = (u16)-1;
blk_trace_setup_lba(bt, bdev);
old_bt = xchg(&q->blk_trace, bt);
if (old_bt != NULL) {
(void)xchg(&q->blk_trace, old_bt);
ret = -EBUSY;
goto free_bt;
}
if (atomic_inc_return(&blk_probes_ref) == 1)
blk_register_tracepoints();
return 0;
free_bt:
blk_trace_free(bt);
return ret;
}
/*
* sysfs interface to enable and configure tracing
*/
static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
struct device_attribute *attr,
char *buf);
static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count);
#define BLK_TRACE_DEVICE_ATTR(_name) \
DEVICE_ATTR(_name, S_IRUGO | S_IWUSR, \
sysfs_blk_trace_attr_show, \
sysfs_blk_trace_attr_store)
static BLK_TRACE_DEVICE_ATTR(enable);
static BLK_TRACE_DEVICE_ATTR(act_mask);
static BLK_TRACE_DEVICE_ATTR(pid);
static BLK_TRACE_DEVICE_ATTR(start_lba);
static BLK_TRACE_DEVICE_ATTR(end_lba);
static struct attribute *blk_trace_attrs[] = {
&dev_attr_enable.attr,
&dev_attr_act_mask.attr,
&dev_attr_pid.attr,
&dev_attr_start_lba.attr,
&dev_attr_end_lba.attr,
NULL
};
struct attribute_group blk_trace_attr_group = {
.name = "trace",
.attrs = blk_trace_attrs,
};
static const struct {
int mask;
const char *str;
} mask_maps[] = {
{ BLK_TC_READ, "read" },
{ BLK_TC_WRITE, "write" },
{ BLK_TC_FLUSH, "flush" },
{ BLK_TC_SYNC, "sync" },
{ BLK_TC_QUEUE, "queue" },
{ BLK_TC_REQUEUE, "requeue" },
{ BLK_TC_ISSUE, "issue" },
{ BLK_TC_COMPLETE, "complete" },
{ BLK_TC_FS, "fs" },
{ BLK_TC_PC, "pc" },
{ BLK_TC_AHEAD, "ahead" },
{ BLK_TC_META, "meta" },
{ BLK_TC_DISCARD, "discard" },
{ BLK_TC_DRV_DATA, "drv_data" },
{ BLK_TC_FUA, "fua" },
};
static int blk_trace_str2mask(const char *str)
{
int i;
int mask = 0;
char *buf, *s, *token;
buf = kstrdup(str, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
s = strstrip(buf);
while (1) {
token = strsep(&s, ",");
if (token == NULL)
break;
if (*token == '\0')
continue;
for (i = 0; i < ARRAY_SIZE(mask_maps); i++) {
if (strcasecmp(token, mask_maps[i].str) == 0) {
mask |= mask_maps[i].mask;
break;
}
}
if (i == ARRAY_SIZE(mask_maps)) {
mask = -EINVAL;
break;
}
}
kfree(buf);
return mask;
}
static ssize_t blk_trace_mask2str(char *buf, int mask)
{
int i;
char *p = buf;
for (i = 0; i < ARRAY_SIZE(mask_maps); i++) {
if (mask & mask_maps[i].mask) {
p += sprintf(p, "%s%s",
(p == buf) ? "" : ",", mask_maps[i].str);
}
}
*p++ = '\n';
return p - buf;
}
static struct request_queue *blk_trace_get_queue(struct block_device *bdev)
{
if (bdev->bd_disk == NULL)
return NULL;
return bdev_get_queue(bdev);
}
static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct hd_struct *p = dev_to_part(dev);
struct request_queue *q;
struct block_device *bdev;
ssize_t ret = -ENXIO;
lock_kernel();
bdev = bdget(part_devt(p));
if (bdev == NULL)
goto out_unlock_kernel;
q = blk_trace_get_queue(bdev);
if (q == NULL)
goto out_bdput;
mutex_lock(&bdev->bd_mutex);
if (attr == &dev_attr_enable) {
ret = sprintf(buf, "%u\n", !!q->blk_trace);
goto out_unlock_bdev;
}
if (q->blk_trace == NULL)
ret = sprintf(buf, "disabled\n");
else if (attr == &dev_attr_act_mask)
ret = blk_trace_mask2str(buf, q->blk_trace->act_mask);
else if (attr == &dev_attr_pid)
ret = sprintf(buf, "%u\n", q->blk_trace->pid);
else if (attr == &dev_attr_start_lba)
ret = sprintf(buf, "%llu\n", q->blk_trace->start_lba);
else if (attr == &dev_attr_end_lba)
ret = sprintf(buf, "%llu\n", q->blk_trace->end_lba);
out_unlock_bdev:
mutex_unlock(&bdev->bd_mutex);
out_bdput:
bdput(bdev);
out_unlock_kernel:
unlock_kernel();
return ret;
}
static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct block_device *bdev;
struct request_queue *q;
struct hd_struct *p;
u64 value;
ssize_t ret = -EINVAL;
if (count == 0)
goto out;
if (attr == &dev_attr_act_mask) {
if (sscanf(buf, "%llx", &value) != 1) {
/* Assume it is a list of trace category names */
ret = blk_trace_str2mask(buf);
if (ret < 0)
goto out;
value = ret;
}
} else if (sscanf(buf, "%llu", &value) != 1)
goto out;
ret = -ENXIO;
lock_kernel();
p = dev_to_part(dev);
bdev = bdget(part_devt(p));
if (bdev == NULL)
goto out_unlock_kernel;
q = blk_trace_get_queue(bdev);
if (q == NULL)
goto out_bdput;
mutex_lock(&bdev->bd_mutex);
if (attr == &dev_attr_enable) {
if (value)
ret = blk_trace_setup_queue(q, bdev);
else
ret = blk_trace_remove_queue(q);
goto out_unlock_bdev;
}
ret = 0;
if (q->blk_trace == NULL)
ret = blk_trace_setup_queue(q, bdev);
if (ret == 0) {
if (attr == &dev_attr_act_mask)
q->blk_trace->act_mask = value;
else if (attr == &dev_attr_pid)
q->blk_trace->pid = value;
else if (attr == &dev_attr_start_lba)
q->blk_trace->start_lba = value;
else if (attr == &dev_attr_end_lba)
q->blk_trace->end_lba = value;
}
out_unlock_bdev:
mutex_unlock(&bdev->bd_mutex);
out_bdput:
bdput(bdev);
out_unlock_kernel:
unlock_kernel();
out:
return ret ? ret : count;
}
int blk_trace_init_sysfs(struct device *dev)
{
return sysfs_create_group(&dev->kobj, &blk_trace_attr_group);
}
void blk_trace_remove_sysfs(struct device *dev)
{
sysfs_remove_group(&dev->kobj, &blk_trace_attr_group);
}
/**
* devt_from_partuuid - looks up the dev_t of a partition by its UUID
* @uuid: char array containing ascii UUID
*
* The function will return the first partition which contains a matching
* UUID value in its partition_meta_info struct. This does not search
* by filesystem UUIDs.
*
* If @uuid is followed by a "/PARTNROFF=%d", then the number will be
* extracted and used as an offset from the partition identified by the UUID.
*
* Returns the matching dev_t on success or 0 on failure.
*/
static dev_t devt_from_partuuid(const char *uuid_str)
{
dev_t res = 0;
struct uuidcmp cmp;
struct device *dev = NULL;
struct gendisk *disk;
struct hd_struct *part;
int offset = 0;
bool clear_root_wait = false;
char *slash;
cmp.uuid = uuid_str;
slash = strchr(uuid_str, '/');
/* Check for optional partition number offset attributes. */
if (slash) {
char c = 0;
/* Explicitly fail on poor PARTUUID syntax. */
if (sscanf(slash + 1,
"PARTNROFF=%d%c", &offset, &c) != 1) {
clear_root_wait = true;
goto done;
}
cmp.len = slash - uuid_str;
} else {
cmp.len = strlen(uuid_str);
}
if (!cmp.len) {
clear_root_wait = true;
goto done;
}
dev = class_find_device(&block_class, NULL, &cmp,
&match_dev_by_uuid);
if (!dev)
goto done;
res = dev->devt;
/* Attempt to find the partition by offset. */
if (!offset)
goto no_offset;
res = 0;
disk = part_to_disk(dev_to_part(dev));
part = disk_get_part(disk, dev_to_part(dev)->partno + offset);
if (part) {
res = part_devt(part);
put_device(part_to_dev(part));
}
no_offset:
put_device(dev);
done:
if (clear_root_wait) {
pr_err("VFS: PARTUUID= is invalid.\n"
"Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
if (root_wait)
pr_err("Disabling rootwait; root= is invalid.\n");
root_wait = 0;
}
return res;
}
static ssize_t part_alignment_offset_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hd_struct *p = dev_to_part(dev);
return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
}
static ssize_t part_ro_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hd_struct *p = dev_to_part(dev);
return sprintf(buf, "%d\n", p->policy ? 1 : 0);
}
ssize_t part_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hd_struct *p = dev_to_part(dev);
return sprintf(buf, "%llu\n",(unsigned long long)part_nr_sects_read(p));
}
static ssize_t part_discard_alignment_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hd_struct *p = dev_to_part(dev);
return sprintf(buf, "%u\n", p->discard_alignment);
}
