static struct device_type disk_type;
+/**
+ * disk_get_part - get partition
+ * @disk: disk to look partition from
+ * @partno: partition number
+ *
+ * Look for partition @partno from @disk. If found, increment
+ * reference count and return it.
+ *
+ * CONTEXT:
+ * Don't care.
+ *
+ * RETURNS:
+ * Pointer to the found partition on success, NULL if not found.
+ */
+struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
+{
+ struct hd_struct *part;
+
+ if (unlikely(partno < 1 || partno > disk_max_parts(disk)))
+ return NULL;
+ rcu_read_lock();
+ part = rcu_dereference(disk->__part[partno - 1]);
+ if (part)
+ get_device(&part->dev);
+ rcu_read_unlock();
+
+ return part;
+}
+EXPORT_SYMBOL_GPL(disk_get_part);
+
+/**
+ * disk_part_iter_init - initialize partition iterator
+ * @piter: iterator to initialize
+ * @disk: disk to iterate over
+ * @flags: DISK_PITER_* flags
+ *
+ * Initialize @piter so that it iterates over partitions of @disk.
+ *
+ * CONTEXT:
+ * Don't care.
+ */
+void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
+ unsigned int flags)
+{
+ piter->disk = disk;
+ piter->part = NULL;
+
+ if (flags & DISK_PITER_REVERSE)
+ piter->idx = disk_max_parts(piter->disk) - 1;
+ else
+ piter->idx = 0;
+
+ piter->flags = flags;
+}
+EXPORT_SYMBOL_GPL(disk_part_iter_init);
+
+/**
+ * disk_part_iter_next - proceed iterator to the next partition and return it
+ * @piter: iterator of interest
+ *
+ * Proceed @piter to the next partition and return it.
+ *
+ * CONTEXT:
+ * Don't care.
+ */
+struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
+{
+ int inc, end;
+
+ /* put the last partition */
+ disk_put_part(piter->part);
+ piter->part = NULL;
+
+ rcu_read_lock();
+
+ /* determine iteration parameters */
+ if (piter->flags & DISK_PITER_REVERSE) {
+ inc = -1;
+ end = -1;
+ } else {
+ inc = 1;
+ end = disk_max_parts(piter->disk);
+ }
+
+ /* iterate to the next partition */
+ for (; piter->idx != end; piter->idx += inc) {
+ struct hd_struct *part;
+
+ part = rcu_dereference(piter->disk->__part[piter->idx]);
+ if (!part)
+ continue;
+ if (!(piter->flags & DISK_PITER_INCL_EMPTY) && !part->nr_sects)
+ continue;
+
+ get_device(&part->dev);
+ piter->part = part;
+ piter->idx += inc;
+ break;
+ }
+
+ rcu_read_unlock();
+
+ return piter->part;
+}
+EXPORT_SYMBOL_GPL(disk_part_iter_next);
+
+/**
+ * disk_part_iter_exit - finish up partition iteration
+ * @piter: iter of interest
+ *
+ * Called when iteration is over. Cleans up @piter.
+ *
+ * CONTEXT:
+ * Don't care.
+ */
+void disk_part_iter_exit(struct disk_part_iter *piter)
+{
+ disk_put_part(piter->part);
+ piter->part = NULL;
+}
+EXPORT_SYMBOL_GPL(disk_part_iter_exit);
+
+/**
+ * disk_map_sector_rcu - map sector to partition
+ * @disk: gendisk of interest
+ * @sector: sector to map
+ *
+ * Find out which partition @sector maps to on @disk. This is
+ * primarily used for stats accounting.
+ *
+ * CONTEXT:
+ * RCU read locked. The returned partition pointer is valid only
+ * while preemption is disabled.
+ *
+ * RETURNS:
+ * Found partition on success, NULL if there's no matching partition.
+ */
+struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
+{
+ int i;
+
+ for (i = 0; i < disk_max_parts(disk); i++) {
+ struct hd_struct *part = rcu_dereference(disk->__part[i]);
+
+ if (part && part->start_sect <= sector &&
+ sector < part->start_sect + part->nr_sects)
+ return part;
+ }
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
+
/*
* Can be deleted altogether. Later.
*
}
#ifdef CONFIG_PROC_FS
-void blkdev_show(struct seq_file *f, off_t offset)
+void blkdev_show(struct seq_file *seqf, off_t offset)
{
struct blk_major_name *dp;
if (offset < BLKDEV_MAJOR_HASH_SIZE) {
mutex_lock(&block_class_lock);
for (dp = major_names[offset]; dp; dp = dp->next)
- seq_printf(f, "%3d %s\n", dp->major, dp->name);
+ seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
mutex_unlock(&block_class_lock);
}
}
EXPORT_SYMBOL(blk_unregister_region);
-static struct kobject *exact_match(dev_t devt, int *part, void *data)
+static struct kobject *exact_match(dev_t devt, int *partno, void *data)
{
struct gendisk *p = data;
int retval;
disk->flags |= GENHD_FL_UP;
- blk_register_region(MKDEV(disk->major, disk->first_minor),
- disk->minors, NULL, exact_match, exact_lock, disk);
+ disk->dev.devt = MKDEV(disk->major, disk->first_minor);
+ blk_register_region(disk_devt(disk), disk->minors, NULL,
+ exact_match, exact_lock, disk);
register_disk(disk);
blk_register_queue(disk);
bdi = &disk->queue->backing_dev_info;
- bdi_register_dev(bdi, MKDEV(disk->major, disk->first_minor));
+ bdi_register_dev(bdi, disk_devt(disk));
retval = sysfs_create_link(&disk->dev.kobj, &bdi->dev->kobj, "bdi");
WARN_ON(retval);
}
sysfs_remove_link(&disk->dev.kobj, "bdi");
bdi_unregister(&disk->queue->backing_dev_info);
blk_unregister_queue(disk);
- blk_unregister_region(MKDEV(disk->major, disk->first_minor),
- disk->minors);
+ blk_unregister_region(disk_devt(disk), disk->minors);
}
/**
* get_gendisk - get partitioning information for a given device
- * @dev: device to get partitioning information for
+ * @devt: device to get partitioning information for
+ * @part: returned partition index
*
* This function gets the structure containing partitioning
- * information for the given device @dev.
+ * information for the given device @devt.
*/
-struct gendisk *get_gendisk(dev_t devt, int *part)
+struct gendisk *get_gendisk(dev_t devt, int *partno)
{
- struct kobject *kobj = kobj_lookup(bdev_map, devt, part);
+ struct kobject *kobj = kobj_lookup(bdev_map, devt, partno);
struct device *dev = kobj_to_dev(kobj);
return kobj ? dev_to_disk(dev) : NULL;
}
-/*
- * print a partitions - intended for places where the root filesystem can't be
- * mounted and thus to give the victim some idea of what went wrong
+/**
+ * bdget_disk - do bdget() by gendisk and partition number
+ * @disk: gendisk of interest
+ * @partno: partition number
+ *
+ * Find partition @partno from @disk, do bdget() on it.
+ *
+ * CONTEXT:
+ * Don't care.
+ *
+ * RETURNS:
+ * Resulting block_device on success, NULL on failure.
*/
-static int printk_partition(struct device *dev, void *data)
+extern struct block_device *bdget_disk(struct gendisk *disk, int partno)
{
- struct gendisk *sgp;
- char buf[BDEVNAME_SIZE];
- int n;
+ dev_t devt = MKDEV(0, 0);
- if (dev->type != &disk_type)
- goto exit;
+ if (partno == 0)
+ devt = disk_devt(disk);
+ else {
+ struct hd_struct *part;
- sgp = dev_to_disk(dev);
- /*
- * Don't show empty devices or things that have been surpressed
- */
- if (get_capacity(sgp) == 0 ||
- (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
- goto exit;
-
- /*
- * Note, unlike /proc/partitions, I am showing the numbers in
- * hex - the same format as the root= option takes.
- */
- printk("%02x%02x %10llu %s",
- sgp->major, sgp->first_minor,
- (unsigned long long)get_capacity(sgp) >> 1,
- disk_name(sgp, 0, buf));
- if (sgp->driverfs_dev != NULL &&
- sgp->driverfs_dev->driver != NULL)
- printk(" driver: %s\n",
- sgp->driverfs_dev->driver->name);
- else
- printk(" (driver?)\n");
-
- /* now show the partitions */
- for (n = 0; n < sgp->minors - 1; ++n) {
- if (sgp->part[n] == NULL)
- goto exit;
- if (sgp->part[n]->nr_sects == 0)
- goto exit;
- printk(" %02x%02x %10llu %s\n",
- sgp->major, n + 1 + sgp->first_minor,
- (unsigned long long)sgp->part[n]->nr_sects >> 1,
- disk_name(sgp, n + 1, buf));
+ part = disk_get_part(disk, partno);
+ if (part && part->nr_sects)
+ devt = part_devt(part);
+ disk_put_part(part);
}
-exit:
- return 0;
+
+ if (likely(devt != MKDEV(0, 0)))
+ return bdget(devt);
+ return NULL;
}
+EXPORT_SYMBOL(bdget_disk);
/*
* print a full list of all partitions - intended for places where the root
*/
void __init printk_all_partitions(void)
{
- mutex_lock(&block_class_lock);
- class_for_each_device(&block_class, NULL, NULL, printk_partition);
- mutex_unlock(&block_class_lock);
+ struct class_dev_iter iter;
+ struct device *dev;
+
+ class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
+ while ((dev = class_dev_iter_next(&iter))) {
+ struct gendisk *disk = dev_to_disk(dev);
+ struct disk_part_iter piter;
+ struct hd_struct *part;
+ char buf[BDEVNAME_SIZE];
+
+ /*
+ * Don't show empty devices or things that have been
+ * surpressed
+ */
+ if (get_capacity(disk) == 0 ||
+ (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
+ continue;
+
+ /*
+ * Note, unlike /proc/partitions, I am showing the
+ * numbers in hex - the same format as the root=
+ * option takes.
+ */
+ printk("%02x%02x %10llu %s",
+ MAJOR(disk_devt(disk)), MINOR(disk_devt(disk)),
+ (unsigned long long)get_capacity(disk) >> 1,
+ disk_name(disk, 0, buf));
+ if (disk->driverfs_dev != NULL &&
+ disk->driverfs_dev->driver != NULL)
+ printk(" driver: %s\n",
+ disk->driverfs_dev->driver->name);
+ else
+ printk(" (driver?)\n");
+
+ /* now show the partitions */
+ disk_part_iter_init(&piter, disk, 0);
+ while ((part = disk_part_iter_next(&piter)))
+ printk(" %02x%02x %10llu %s\n",
+ MAJOR(part_devt(part)), MINOR(part_devt(part)),
+ (unsigned long long)part->nr_sects >> 1,
+ disk_name(disk, part->partno, buf));
+ disk_part_iter_exit(&piter);
+ }
+ class_dev_iter_exit(&iter);
}
#ifdef CONFIG_PROC_FS
/* iterator */
-static int find_start(struct device *dev, void *data)
+static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
{
- loff_t *k = data;
+ loff_t skip = *pos;
+ struct class_dev_iter *iter;
+ struct device *dev;
- if (dev->type != &disk_type)
- return 0;
- if (!*k)
- return 1;
- (*k)--;
- return 0;
+ iter = kmalloc(GFP_KERNEL, sizeof(*iter));
+ if (!iter)
+ return ERR_PTR(-ENOMEM);
+
+ seqf->private = iter;
+ class_dev_iter_init(iter, &block_class, NULL, &disk_type);
+ do {
+ dev = class_dev_iter_next(iter);
+ if (!dev)
+ return NULL;
+ } while (skip--);
+
+ return dev_to_disk(dev);
}
-static void *part_start(struct seq_file *part, loff_t *pos)
+static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
{
struct device *dev;
- loff_t k = *pos;
-
- if (!k)
- part->private = (void *)1LU; /* tell show to print header */
- mutex_lock(&block_class_lock);
- dev = class_find_device(&block_class, NULL, &k, find_start);
- if (dev) {
- put_device(dev);
+ (*pos)++;
+ dev = class_dev_iter_next(seqf->private);
+ if (dev)
return dev_to_disk(dev);
- }
+
return NULL;
}
-static int find_next(struct device *dev, void *data)
+static void disk_seqf_stop(struct seq_file *seqf, void *v)
{
- if (dev->type == &disk_type)
- return 1;
- return 0;
-}
+ struct class_dev_iter *iter = seqf->private;
-static void *part_next(struct seq_file *part, void *v, loff_t *pos)
-{
- struct gendisk *gp = v;
- struct device *dev;
- ++*pos;
- dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
- if (dev) {
- put_device(dev);
- return dev_to_disk(dev);
+ /* stop is called even after start failed :-( */
+ if (iter) {
+ class_dev_iter_exit(iter);
+ kfree(iter);
}
- return NULL;
}
-static void part_stop(struct seq_file *part, void *v)
+static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
{
- mutex_unlock(&block_class_lock);
+ static void *p;
+
+ p = disk_seqf_start(seqf, pos);
+ if (!IS_ERR(p) && p)
+ seq_puts(seqf, "major minor #blocks name\n\n");
+ return p;
}
-static int show_partition(struct seq_file *part, void *v)
+static int show_partition(struct seq_file *seqf, void *v)
{
struct gendisk *sgp = v;
- int n;
+ struct disk_part_iter piter;
+ struct hd_struct *part;
char buf[BDEVNAME_SIZE];
- /*
- * Print header if start told us to do. This is to preserve
- * the original behavior of not printing header if no
- * partition exists. This hackery will be removed later with
- * class iteration clean up.
- */
- if (part->private) {
- seq_puts(part, "major minor #blocks name\n\n");
- part->private = NULL;
- }
-
/* Don't show non-partitionable removeable devices or empty devices */
- if (!get_capacity(sgp) ||
- (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
+ if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
+ (sgp->flags & GENHD_FL_REMOVABLE)))
return 0;
if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
return 0;
/* show the full disk and all non-0 size partitions of it */
- seq_printf(part, "%4d %4d %10llu %s\n",
- sgp->major, sgp->first_minor,
+ seq_printf(seqf, "%4d %4d %10llu %s\n",
+ MAJOR(disk_devt(sgp)), MINOR(disk_devt(sgp)),
(unsigned long long)get_capacity(sgp) >> 1,
disk_name(sgp, 0, buf));
- for (n = 0; n < sgp->minors - 1; n++) {
- if (!sgp->part[n])
- continue;
- if (sgp->part[n]->nr_sects == 0)
- continue;
- seq_printf(part, "%4d %4d %10llu %s\n",
- sgp->major, n + 1 + sgp->first_minor,
- (unsigned long long)sgp->part[n]->nr_sects >> 1 ,
- disk_name(sgp, n + 1, buf));
- }
+
+ disk_part_iter_init(&piter, sgp, 0);
+ while ((part = disk_part_iter_next(&piter)))
+ seq_printf(seqf, "%4d %4d %10llu %s\n",
+ MAJOR(part_devt(part)), MINOR(part_devt(part)),
+ (unsigned long long)part->nr_sects >> 1,
+ disk_name(sgp, part->partno, buf));
+ disk_part_iter_exit(&piter);
return 0;
}
const struct seq_operations partitions_op = {
- .start = part_start,
- .next = part_next,
- .stop = part_stop,
+ .start = show_partition_start,
+ .next = disk_seqf_next,
+ .stop = disk_seqf_stop,
.show = show_partition
};
#endif
-static struct kobject *base_probe(dev_t devt, int *part, void *data)
+static struct kobject *base_probe(dev_t devt, int *partno, void *data)
{
if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
/* Make old-style 2.4 aliases work */
struct gendisk *disk = dev_to_disk(dev);
kfree(disk->random);
- kfree(disk->part);
+ kfree(disk->__part);
free_disk_stats(disk);
kfree(disk);
}
* The output looks suspiciously like /proc/partitions with a bunch of
* extra fields.
*/
-
-static void *diskstats_start(struct seq_file *part, loff_t *pos)
-{
- struct device *dev;
- loff_t k = *pos;
-
- mutex_lock(&block_class_lock);
- dev = class_find_device(&block_class, NULL, &k, find_start);
- if (dev) {
- put_device(dev);
- return dev_to_disk(dev);
- }
- return NULL;
-}
-
-static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
-{
- struct gendisk *gp = v;
- struct device *dev;
-
- ++*pos;
- dev = class_find_device(&block_class, &gp->dev, NULL, find_next);
- if (dev) {
- put_device(dev);
- return dev_to_disk(dev);
- }
- return NULL;
-}
-
-static void diskstats_stop(struct seq_file *part, void *v)
-{
- mutex_unlock(&block_class_lock);
-}
-
-static int diskstats_show(struct seq_file *s, void *v)
+static int diskstats_show(struct seq_file *seqf, void *v)
{
struct gendisk *gp = v;
+ struct disk_part_iter piter;
+ struct hd_struct *hd;
char buf[BDEVNAME_SIZE];
- int n = 0;
/*
if (&gp->dev.kobj.entry == block_class.devices.next)
- seq_puts(s, "major minor name"
+ seq_puts(seqf, "major minor name"
" rio rmerge rsect ruse wio wmerge "
"wsect wuse running use aveq"
"\n\n");
preempt_disable();
disk_round_stats(gp);
preempt_enable();
- seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
- gp->major, n + gp->first_minor, disk_name(gp, n, buf),
+ seq_printf(seqf, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
+ MAJOR(disk_devt(gp)), MINOR(disk_devt(gp)),
+ disk_name(gp, 0, buf),
disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
(unsigned long long)disk_stat_read(gp, sectors[0]),
jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));
/* now show all non-0 size partitions of it */
- for (n = 0; n < gp->minors - 1; n++) {
- struct hd_struct *hd = gp->part[n];
-
- if (!hd || !hd->nr_sects)
- continue;
-
+ disk_part_iter_init(&piter, gp, 0);
+ while ((hd = disk_part_iter_next(&piter))) {
preempt_disable();
part_round_stats(hd);
preempt_enable();
- seq_printf(s, "%4d %4d %s %lu %lu %llu "
+ seq_printf(seqf, "%4d %4d %s %lu %lu %llu "
"%u %lu %lu %llu %u %u %u %u\n",
- gp->major, n + gp->first_minor + 1,
- disk_name(gp, n + 1, buf),
+ MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
+ disk_name(gp, hd->partno, buf),
part_stat_read(hd, ios[0]),
part_stat_read(hd, merges[0]),
(unsigned long long)part_stat_read(hd, sectors[0]),
jiffies_to_msecs(part_stat_read(hd, time_in_queue))
);
}
+ disk_part_iter_exit(&piter);
return 0;
}
const struct seq_operations diskstats_op = {
- .start = diskstats_start,
- .next = diskstats_next,
- .stop = diskstats_stop,
+ .start = disk_seqf_start,
+ .next = disk_seqf_next,
+ .stop = disk_seqf_stop,
.show = diskstats_show
};
#endif /* CONFIG_PROC_FS */
EXPORT_SYMBOL_GPL(genhd_media_change_notify);
#endif /* 0 */
-struct find_block {
- const char *name;
- int part;
-};
-
-static int match_id(struct device *dev, void *data)
+dev_t blk_lookup_devt(const char *name, int partno)
{
- struct find_block *find = data;
+ dev_t devt = MKDEV(0, 0);
+ struct class_dev_iter iter;
+ struct device *dev;
- if (dev->type != &disk_type)
- return 0;
- if (strcmp(dev->bus_id, find->name) == 0) {
+ class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
+ while ((dev = class_dev_iter_next(&iter))) {
struct gendisk *disk = dev_to_disk(dev);
- if (find->part < disk->minors)
- return 1;
- }
- return 0;
-}
-dev_t blk_lookup_devt(const char *name, int part)
-{
- struct device *dev;
- dev_t devt = MKDEV(0, 0);
- struct find_block find;
+ if (strcmp(dev->bus_id, name))
+ continue;
+ if (partno < 0 || partno > disk_max_parts(disk))
+ continue;
- mutex_lock(&block_class_lock);
- find.name = name;
- find.part = part;
- dev = class_find_device(&block_class, NULL, &find, match_id);
- if (dev) {
- put_device(dev);
- devt = MKDEV(MAJOR(dev->devt),
- MINOR(dev->devt) + part);
- }
- mutex_unlock(&block_class_lock);
+ if (partno == 0)
+ devt = disk_devt(disk);
+ else {
+ struct hd_struct *part;
+
+ part = disk_get_part(disk, partno);
+ if (!part || !part->nr_sects) {
+ disk_put_part(part);
+ continue;
+ }
+ devt = part_devt(part);
+ disk_put_part(part);
+ }
+ break;
+ }
+ class_dev_iter_exit(&iter);
return devt;
}
EXPORT_SYMBOL(blk_lookup_devt);
}
if (minors > 1) {
int size = (minors - 1) * sizeof(struct hd_struct *);
- disk->part = kmalloc_node(size,
+ disk->__part = kmalloc_node(size,
GFP_KERNEL | __GFP_ZERO, node_id);
- if (!disk->part) {
+ if (!disk->__part) {
free_disk_stats(disk);
kfree(disk);
return NULL;
void set_disk_ro(struct gendisk *disk, int flag)
{
- int i;
+ struct disk_part_iter piter;
+ struct hd_struct *part;
+
disk->policy = flag;
- for (i = 0; i < disk->minors - 1; i++)
- if (disk->part[i]) disk->part[i]->policy = flag;
+ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
+ while ((part = disk_part_iter_next(&piter)))
+ part->policy = flag;
+ disk_part_iter_exit(&piter);
}
EXPORT_SYMBOL(set_disk_ro);
EXPORT_SYMBOL(bdev_read_only);
-int invalidate_partition(struct gendisk *disk, int index)
+int invalidate_partition(struct gendisk *disk, int partno)
{
int res = 0;
- struct block_device *bdev = bdget_disk(disk, index);
+ struct block_device *bdev = bdget_disk(disk, partno);
if (bdev) {
fsync_bdev(bdev);
res = __invalidate_device(bdev);
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff