Release 4.7 drivers/block/brd.c

/*
 * Ram backed block device driver.
 *
 * Copyright (C) 2007 Nick Piggin
 * Copyright (C) 2007 Novell Inc.
 *
 * Parts derived from drivers/block/rd.c, and drivers/block/loop.c, copyright
 * of their respective owners.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/bio.h>
#include <linux/highmem.h>
#include <linux/mutex.h>
#include <linux/radix-tree.h>
#include <linux/fs.h>
#include <linux/slab.h>
#ifdef CONFIG_BLK_DEV_RAM_DAX
#include <linux/pfn_t.h>
#endif

#include <asm/uaccess.h>


#define SECTOR_SHIFT		9

#define PAGE_SECTORS_SHIFT	(PAGE_SHIFT - SECTOR_SHIFT)

#define PAGE_SECTORS		(1 << PAGE_SECTORS_SHIFT)

/*
 * Each block ramdisk device has a radix_tree brd_pages of pages that stores
 * the pages containing the block device's contents. A brd page's ->index is
 * its offset in PAGE_SIZE units. This is similar to, but in no way connected
 * with, the kernel's pagecache or buffer cache (which sit above our block
 * device).
 */

struct brd_device {
	
int		brd_number;

	
struct request_queue	*brd_queue;
	
struct gendisk		*brd_disk;
	
struct list_head	brd_list;

	/*
         * Backing store of pages and lock to protect it. This is the contents
         * of the block device.
         */
	
spinlock_t		brd_lock;
	
struct radix_tree_root	brd_pages;
};

/*
 * Look up and return a brd's page for a given sector.
 */
static DEFINE_MUTEX(brd_mutex);


static struct page *brd_lookup_page(struct brd_device *brd, sector_t sector)
{
	pgoff_t idx;
	struct page *page;

	/*
         * The page lifetime is protected by the fact that we have opened the
         * device node -- brd pages will never be deleted under us, so we
         * don't need any further locking or refcounting.
         *
         * This is strictly true for the radix-tree nodes as well (ie. we
         * don't actually need the rcu_read_lock()), however that is not a
         * documented feature of the radix-tree API so it is better to be
         * safe here (we don't have total exclusion from radix tree updates
         * here, only deletes).
         */
	rcu_read_lock();
	idx = sector >> PAGE_SECTORS_SHIFT; /* sector to page index */
	page = radix_tree_lookup(&brd->brd_pages, idx);
	rcu_read_unlock();

	BUG_ON(page && page->index != idx);

	return page;
}

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/*
 * Look up and return a brd's page for a given sector.
 * If one does not exist, allocate an empty page, and insert that. Then
 * return it.
 */


static struct page *brd_insert_page(struct brd_device *brd, sector_t sector)
{
	pgoff_t idx;
	struct page *page;
	gfp_t gfp_flags;

	page = brd_lookup_page(brd, sector);
	if (page)
		return page;

	/*
         * Must use NOIO because we don't want to recurse back into the
         * block or filesystem layers from page reclaim.
         *
         * Cannot support DAX and highmem, because our ->direct_access
         * routine for DAX must return memory that is always addressable.
         * If DAX was reworked to use pfns and kmap throughout, this
         * restriction might be able to be lifted.
         */
	gfp_flags = GFP_NOIO | __GFP_ZERO;
#ifndef CONFIG_BLK_DEV_RAM_DAX
	gfp_flags |= __GFP_HIGHMEM;
#endif
	page = alloc_page(gfp_flags);
	if (!page)
		return NULL;

	if (radix_tree_preload(GFP_NOIO)) {
		__free_page(page);
		return NULL;
	}

	spin_lock(&brd->brd_lock);
	idx = sector >> PAGE_SECTORS_SHIFT;
	page->index = idx;
	if (radix_tree_insert(&brd->brd_pages, idx, page)) {
		__free_page(page);
		page = radix_tree_lookup(&brd->brd_pages, idx);
		BUG_ON(!page);
		BUG_ON(page->index != idx);
	}
	spin_unlock(&brd->brd_lock);

	radix_tree_preload_end();

	return page;
}

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2
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linus torvalds
linus torvalds
17
9.83%
1
12.50%
brian behlendorf
brian behlendorf
6
3.47%
1
12.50%
matthew wilcox
matthew wilcox
2
1.16%
1
12.50%
petr tesarik
petr tesarik
1
0.58%
1
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173
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8
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static void brd_free_page(struct brd_device *brd, sector_t sector)
{
	struct page *page;
	pgoff_t idx;

	spin_lock(&brd->brd_lock);
	idx = sector >> PAGE_SECTORS_SHIFT;
	page = radix_tree_delete(&brd->brd_pages, idx);
	spin_unlock(&brd->brd_lock);
	if (page)
		__free_page(page);
}

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static void brd_zero_page(struct brd_device *brd, sector_t sector)
{
	struct page *page;

	page = brd_lookup_page(brd, sector);
	if (page)
		clear_highpage(page);
}

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/*
 * Free all backing store pages and radix tree. This must only be called when
 * there are no other users of the device.
 */

#define FREE_BATCH 16


static void brd_free_pages(struct brd_device *brd)
{
	unsigned long pos = 0;
	struct page *pages[FREE_BATCH];
	int nr_pages;

	do {
		int i;

		nr_pages = radix_tree_gang_lookup(&brd->brd_pages,
				(void **)pages, pos, FREE_BATCH);

		for (i = 0; i < nr_pages; i++) {
			void *ret;

			BUG_ON(pages[i]->index < pos);
			pos = pages[i]->index;
			ret = radix_tree_delete(&brd->brd_pages, pos);
			BUG_ON(!ret || ret != pages[i]);
			__free_page(pages[i]);
		}

		pos++;

		/*
                 * This assumes radix_tree_gang_lookup always returns as
                 * many pages as possible. If the radix-tree code changes,
                 * so will this have to.
                 */
	} while (nr_pages == FREE_BATCH);
}

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/*
 * copy_to_brd_setup must be called before copy_to_brd. It may sleep.
 */


static int copy_to_brd_setup(struct brd_device *brd, sector_t sector, size_t n)
{
	unsigned int offset = (sector & (PAGE_SECTORS-1)) << SECTOR_SHIFT;
	size_t copy;

	copy = min_t(size_t, n, PAGE_SIZE - offset);
	if (!brd_insert_page(brd, sector))
		return -ENOSPC;
	if (copy < n) {
		sector += copy >> SECTOR_SHIFT;
		if (!brd_insert_page(brd, sector))
			return -ENOSPC;
	}
	return 0;
}

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2
40.00%
linus torvalds
linus torvalds
4
4.26%
1
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matthew wilcox
matthew wilcox
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static void discard_from_brd(struct brd_device *brd,
			sector_t sector, size_t n)
{
	while (n >= PAGE_SIZE) {
		/*
                 * Don't want to actually discard pages here because
                 * re-allocating the pages can result in writeback
                 * deadlocks under heavy load.
                 */
		if (0)
			brd_free_page(brd, sector);
		else
			brd_zero_page(brd, sector);
		sector += PAGE_SIZE >> SECTOR_SHIFT;
		n -= PAGE_SIZE;
	}
}

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/*
 * Copy n bytes from src to the brd starting at sector. Does not sleep.
 */


static void copy_to_brd(struct brd_device *brd, const void *src,
			sector_t sector, size_t n)
{
	struct page *page;
	void *dst;
	unsigned int offset = (sector & (PAGE_SECTORS-1)) << SECTOR_SHIFT;
	size_t copy;

	copy = min_t(size_t, n, PAGE_SIZE - offset);
	page = brd_lookup_page(brd, sector);
	BUG_ON(!page);

	dst = kmap_atomic(page);
	memcpy(dst + offset, src, copy);
	kunmap_atomic(dst);

	if (copy < n) {
		src += copy;
		sector += copy >> SECTOR_SHIFT;
		copy = n - copy;
		page = brd_lookup_page(brd, sector);
		BUG_ON(!page);

		dst = kmap_atomic(page);
		memcpy(dst, src, copy);
		kunmap_atomic(dst);
	}
}

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linus torvalds
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31.06%
3
33.33%
andrew morton
andrew morton
11
6.83%
2
22.22%
christian borntraeger
christian borntraeger
7
4.35%
1
11.11%
al viro
al viro
5
3.11%
1
11.11%
russell king
russell king
1
0.62%
1
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161
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9
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/*
 * Copy n bytes to dst from the brd starting at sector. Does not sleep.
 */


static void copy_from_brd(void *dst, struct brd_device *brd,
			sector_t sector, size_t n)
{
	struct page *page;
	void *src;
	unsigned int offset = (sector & (PAGE_SECTORS-1)) << SECTOR_SHIFT;
	size_t copy;

	copy = min_t(size_t, n, PAGE_SIZE - offset);
	page = brd_lookup_page(brd, sector);
	if (page) {
		src = kmap_atomic(page);
		memcpy(dst, src + offset, copy);
		kunmap_atomic(src);
	} else
		memset(dst, 0, copy);

	if (copy < n) {
		dst += copy;
		sector += copy >> SECTOR_SHIFT;
		copy = n - copy;
		page = brd_lookup_page(brd, sector);
		if (page) {
			src = kmap_atomic(page);
			memcpy(dst, src, copy);
			kunmap_atomic(src);
		} else
			memset(dst, 0, copy);
	}
}

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15.00%
3
42.86%
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al viro
13
7.22%
1
14.29%
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pre-git
9
5.00%
2
28.57%
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180
100.00%
7
100.00%

/*
 * Process a single bvec of a bio.
 */


static int brd_do_bvec(struct brd_device *brd, struct page *page,
			unsigned int len, unsigned int off, int rw,
			sector_t sector)
{
	void *mem;
	int err = 0;

	if (rw != READ) {
		err = copy_to_brd_setup(brd, sector, len);
		if (err)
			goto out;
	}

	mem = kmap_atomic(page);
	if (rw == READ) {
		copy_from_brd(mem + off, brd, sector, len);
		flush_dcache_page(page);
	} else {
		flush_dcache_page(page);
		copy_to_brd(brd, mem + off, sector, len);
	}
	kunmap_atomic(mem);

out:
	return err;
}

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linus torvalds
7
5.43%
2
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al viro
5
3.88%
2
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129
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8
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static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
{
	struct block_device *bdev = bio->bi_bdev;
	struct brd_device *brd = bdev->bd_disk->private_data;
	int rw;
	struct bio_vec bvec;
	sector_t sector;
	struct bvec_iter iter;

	sector = bio->bi_iter.bi_sector;
	if (bio_end_sector(bio) > get_capacity(bdev->bd_disk))
		goto io_error;

	if (unlikely(bio->bi_rw & REQ_DISCARD)) {
		if (sector & ((PAGE_SIZE >> SECTOR_SHIFT) - 1) ||
		    bio->bi_iter.bi_size & ~PAGE_MASK)
			goto io_error;
		discard_from_brd(brd, sector, bio->bi_iter.bi_size);
		goto out;
	}

	rw = bio_rw(bio);
	if (rw == READA)
		rw = READ;

	bio_for_each_segment(bvec, bio, iter) {
		unsigned int len = bvec.bv_len;
		int err;

		err = brd_do_bvec(brd, bvec.bv_page, len,
					bvec.bv_offset, rw, sector);
		if (err)
			goto io_error;
		sector += len >> SECTOR_SHIFT;
	}

out:
	bio_endio(bio);
	return BLK_QC_T_NONE;
io_error:
	bio_io_error(bio);
	return BLK_QC_T_NONE;
}

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christoph hellwig
christoph hellwig
18
8.11%
2
20.00%
kent overstreet
kent overstreet
14
6.31%
3
30.00%
jens axboe
jens axboe
7
3.15%
1
10.00%
bart van assche
bart van assche
1
0.45%
1
10.00%
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222
100.00%
10
100.00%



static int brd_rw_page(struct block_device *bdev, sector_t sector,
		       struct page *page, int rw)
{
	struct brd_device *brd = bdev->bd_disk->private_data;
	int err = brd_do_bvec(brd, page, PAGE_SIZE, 0, rw, sector);
	page_endio(page, rw & WRITE, err);
	return err;
}

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65
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2
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#ifdef CONFIG_BLK_DEV_RAM_DAX


static long brd_direct_access(struct block_device *bdev, sector_t sector,
			void __pmem **kaddr, pfn_t *pfn, long size)
{
	struct brd_device *brd = bdev->bd_disk->private_data;
	struct page *page;

	if (!brd)
		return -ENODEV;
	page = brd_insert_page(brd, sector);
	if (!page)
		return -ENOSPC;
	*kaddr = (void __pmem *)page_address(page);
	*pfn = page_to_pfn_t(page);

	return PAGE_SIZE;
}
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ross zwisler
6
6.38%
1
14.29%
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dan williams
5
5.32%
2
28.57%
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matthew wilcox
3
3.19%
2
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94
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7
100.00%

#else

#define brd_direct_access NULL
#endif



static int brd_ioctl(struct block_device *bdev, fmode_t mode,
			unsigned int cmd, unsigned long arg)
{
	int error;
	struct brd_device *brd = bdev->bd_disk->private_data;

	if (cmd != BLKFLSBUF)
		return -ENOTTY;

	/*
         * ram device BLKFLSBUF has special semantics, we want to actually
         * release and destroy the ramdisk data.
         */
	mutex_lock(&brd_mutex);
	mutex_lock(&bdev->bd_mutex);
	error = -EBUSY;
	if (bdev->bd_openers <= 1) {
		/*
                 * Kill the cache first, so it isn't written back to the
                 * device.
                 *
                 * Another thread might instantiate more buffercache here,
                 * but there is not much we can do to close that race.
                 */
		kill_bdev(bdev);
		brd_free_pages(brd);
		error = 0;
	}
	mutex_unlock(&bdev->bd_mutex);
	mutex_unlock(&brd_mutex);

	return error;
}

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linus torvalds
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8.33%
2
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al viro
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27.27%
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pre-git
7
6.48%
2
18.18%
arjan van de ven
arjan van de ven
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1.85%
1
9.09%
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11
100.00%


static const struct block_device_operations brd_fops = {
	.owner =		THIS_MODULE,
	.rw_page =		brd_rw_page,
	.ioctl =		brd_ioctl,
	.direct_access =	brd_direct_access,
};

/*
 * And now the modules code and kernel interface.
 */

static int rd_nr = CONFIG_BLK_DEV_RAM_COUNT;
module_param(rd_nr, int, S_IRUGO);
MODULE_PARM_DESC(rd_nr, "Maximum number of brd devices");


int rd_size = CONFIG_BLK_DEV_RAM_SIZE;
module_param(rd_size, int, S_IRUGO);
MODULE_PARM_DESC(rd_size, "Size of each RAM disk in kbytes.");


static int max_part = 1;
module_param(max_part, int, S_IRUGO);
MODULE_PARM_DESC(max_part, "Num Minors to reserve between devices");

MODULE_LICENSE("GPL");

MODULE_ALIAS_BLOCKDEV_MAJOR(RAMDISK_MAJOR);
MODULE_ALIAS("rd");

#ifndef MODULE
/* Legacy boot options - nonmodular */


static int __init ramdisk_size(char *str)
{
	rd_size = simple_strtol(str, NULL, 0);
	return 1;
}
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__setup("ramdisk_size=", ramdisk_size);
#endif

/*
 * The device scheme is derived from loop.c. Keep them in synch where possible
 * (should share code eventually).
 */
static LIST_HEAD(brd_devices);
static DEFINE_MUTEX(brd_devices_mutex);



static struct brd_device *brd_alloc(int i)
{
	struct brd_device *brd;
	struct gendisk *disk;

	brd = kzalloc(sizeof(*brd), GFP_KERNEL);
	if (!brd)
		goto out;
	brd->brd_number		= i;
	spin_lock_init(&brd->brd_lock);
	INIT_RADIX_TREE(&brd->brd_pages, GFP_ATOMIC);

	brd->brd_queue = blk_alloc_queue(GFP_KERNEL);
	if (!brd->brd_queue)
		goto out_free_dev;

	blk_queue_make_request(brd->brd_queue, brd_make_request);
	blk_queue_max_hw_sectors(brd->brd_queue, 1024);
	blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY);

	/* This is so fdisk will align partitions on 4k, because of
         * direct_access API needing 4k alignment, returning a PFN
         * (This is only a problem on very small devices <= 4M,
         *  otherwise fdisk will align on 1M. Regardless this call
         *  is harmless)
         */
	blk_queue_physical_block_size(brd->brd_queue, PAGE_SIZE);

	brd->brd_queue->limits.discard_granularity = PAGE_SIZE;
	blk_queue_max_discard_sectors(brd->brd_queue, UINT_MAX);
	brd->brd_queue->limits.discard_zeroes_data = 1;
	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, brd->brd_queue);

	disk = brd->brd_disk = alloc_disk(max_part);
	if (!disk)
		goto out_free_queue;
	disk->major		= RAMDISK_MAJOR;
	disk->first_minor	= i * max_part;
	disk->fops		= &brd_fops;
	disk->private_data	= brd;
	disk->queue		= brd->brd_queue;
	disk->flags		= GENHD_FL_EXT_DEVT;
	sprintf(disk->disk_name, "ram%d", i);
	set_capacity(disk, rd_size * 2);

	return brd;

out_free_queue:
	blk_cleanup_queue(brd->brd_queue);
out_free_dev:
	kfree(brd);
out:
	return NULL;
}

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5
23.81%
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boaz harrosh
15
5.68%
2
9.52%
linus torvalds
linus torvalds
9
3.41%
3
14.29%
eric w. biederman
eric w. biederman
8
3.03%
1
4.76%
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pre-git
5
1.89%
3
14.29%
marcin krol
marcin krol
4
1.52%
1
4.76%
jens axboe
jens axboe
4
1.52%
1
4.76%
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martin k. petersen
1
0.38%
1
4.76%
Total
264
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21
100.00%



static void brd_free(struct brd_device *brd)
{
	put_disk(brd->brd_disk);
	blk_cleanup_queue(brd->brd_queue);
	brd_free_pages(brd);
	kfree(brd);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
32
91.43%
1
50.00%
pre-git
pre-git
3
8.57%
1
50.00%
Total
35
100.00%
2
100.00%



static struct brd_device *brd_init_one(int i, bool *new)
{
	struct brd_device *brd;

	*new = false;
	list_for_each_entry(brd, &brd_devices, brd_list) {
		if (brd->brd_number == i)
			goto out;
	}

	brd = brd_alloc(i);
	if (brd) {
		add_disk(brd->brd_disk);
		list_add_tail(&brd->brd_list, &brd_devices);
	}
	*new = true;
out:
	return brd;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
51
58.62%
1
10.00%
boaz harrosh
boaz harrosh
14
16.09%
1
10.00%
linus torvalds
linus torvalds
11
12.64%
3
30.00%
pre-git
pre-git
10
11.49%
4
40.00%
al viro
al viro
1
1.15%
1
10.00%
Total
87
100.00%
10
100.00%



static void brd_del_one(struct brd_device *brd)
{
	list_del(&brd->brd_list);
	del_gendisk(brd->brd_disk);
	brd_free(brd);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
21
67.74%
1
20.00%
al viro
al viro
7
22.58%
3
60.00%
jeff garzik
jeff garzik
3
9.68%
1
20.00%
Total
31
100.00%
5
100.00%



static struct kobject *brd_probe(dev_t dev, int *part, void *data)
{
	struct brd_device *brd;
	struct kobject *kobj;
	bool new;

	mutex_lock(&brd_devices_mutex);
	brd = brd_init_one(MINOR(dev) / max_part, &new);
	kobj = brd ? get_disk(brd->brd_disk) : NULL;
	mutex_unlock(&brd_devices_mutex);

	if (new)
		*part = 0;

	return kobj;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
58
69.05%
1
16.67%
boaz harrosh
boaz harrosh
12
14.29%
1
16.67%
peter zijlstra
peter zijlstra
6
7.14%
1
16.67%
pre-git
pre-git
4
4.76%
1
16.67%
namhyung kim
namhyung kim
3
3.57%
1
16.67%
mikulas patocka
mikulas patocka
1
1.19%
1
16.67%
Total
84
100.00%
6
100.00%



static int __init brd_init(void)
{
	struct brd_device *brd, *next;
	int i;

	/*
         * brd module now has a feature to instantiate underlying device
         * structure on-demand, provided that there is an access dev node.
         *
         * (1) if rd_nr is specified, create that many upfront. else
         *     it defaults to CONFIG_BLK_DEV_RAM_COUNT
         * (2) User can further extend brd devices by create dev node themselves
         *     and have kernel automatically instantiate actual device
         *     on-demand. Example:
         *              mknod /path/devnod_name b 1 X   # 1 is the rd major
         *              fdisk -l /path/devnod_name
         *      If (X / max_part) was not already created it will be created
         *      dynamically.
         */

	if (register_blkdev(RAMDISK_MAJOR, "ramdisk"))
		return -EIO;

	if (unlikely(!max_part))
		max_part = 1;

	for (i = 0; i < rd_nr; i++) {
		brd = brd_alloc(i);
		if (!brd)
			goto out_free;
		list_add_tail(&brd->brd_list, &brd_devices);
	}

	/* point of no return */

	list_for_each_entry(brd, &brd_devices, brd_list)
		add_disk(brd->brd_disk);

	blk_register_region(MKDEV(RAMDISK_MAJOR, 0), 1UL << MINORBITS,
				  THIS_MODULE, brd_probe, NULL, NULL);

	pr_info("brd: module loaded\n");
	return 0;

out_free:
	list_for_each_entry_safe(brd, next, &brd_devices, brd_list) {
		list_del(&brd->brd_list);
		brd_free(brd);
	}
	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");

	pr_info("brd: module NOT loaded !!!\n");
	return -ENOMEM;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
76
43.18%
1
5.56%
pre-git
pre-git
43
24.43%
6
33.33%
boaz harrosh
boaz harrosh
26
14.77%
1
5.56%
al viro
al viro
8
4.55%
3
16.67%
linus torvalds
linus torvalds
8
4.55%
1
5.56%
peter zijlstra
peter zijlstra
7
3.98%
1
5.56%
andrew morton
andrew morton
5
2.84%
2
11.11%
christoph hellwig
christoph hellwig
1
0.57%
1
5.56%
akinobu mita
akinobu mita
1
0.57%
1
5.56%
eric w. biederman
eric w. biederman
1
0.57%
1
5.56%
Total
176
100.00%
18
100.00%



static void __exit brd_exit(void)
{
	struct brd_device *brd, *next;

	list_for_each_entry_safe(brd, next, &brd_devices, brd_list)
		brd_del_one(brd);

	blk_unregister_region(MKDEV(RAMDISK_MAJOR, 0), 1UL << MINORBITS);
	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");

	pr_info("brd: module unloaded\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
27
46.55%
1
14.29%
linus torvalds
linus torvalds
12
20.69%
1
14.29%
pre-git
pre-git
10
17.24%
3
42.86%
boaz harrosh
boaz harrosh
8
13.79%
1
14.29%
stephen hemminger
stephen hemminger
1
1.72%
1
14.29%
Total
58
100.00%
7
100.00%


module_init(brd_init);

module_exit(brd_exit);

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
nick piggin
nick piggin
1734
66.51%
5
4.95%
linus torvalds
linus torvalds
175
6.71%
8
7.92%
andrew morton
andrew morton
124
4.76%
14
13.86%
pre-git
pre-git
120
4.60%
17
16.83%
boaz harrosh
boaz harrosh
88
3.38%
2
1.98%
matthew wilcox
matthew wilcox
84
3.22%
4
3.96%
al viro
al viro
64
2.45%
11
10.89%
christoph hellwig
christoph hellwig
27
1.04%
5
4.95%
jan kara
jan kara
25
0.96%
1
0.99%
arnd bergmann
arnd bergmann
22
0.84%
2
1.98%
dmitriy monakhov
dmitriy monakhov
14
0.54%
1
0.99%
jared hulbert
jared hulbert
14
0.54%
1
0.99%
kent overstreet
kent overstreet
14
0.54%
3
2.97%
peter zijlstra
peter zijlstra
13
0.50%
1
0.99%
dan williams
dan williams
13
0.50%
2
1.98%
jens axboe
jens axboe
11
0.42%
2
1.98%
eric w. biederman
eric w. biederman
9
0.35%
1
0.99%
christian borntraeger
christian borntraeger
7
0.27%
1
0.99%
stephen hemminger
stephen hemminger
7
0.27%
1
0.99%
brian behlendorf
brian behlendorf
6
0.23%
1
0.99%
ross zwisler
ross zwisler
6
0.23%
1
0.99%
namhyung kim
namhyung kim
5
0.19%
2
1.98%
marcin krol
marcin krol
4
0.15%
1
0.99%
jeff garzik
jeff garzik
3
0.12%
1
0.99%
tejun heo
tejun heo
3
0.12%
1
0.99%
robert p. j. day
robert p. j. day
3
0.12%
2
1.98%
laurent vivier
laurent vivier
2
0.08%
1
0.99%
arjan van de ven
arjan van de ven
2
0.08%
1
0.99%
petr tesarik
petr tesarik
1
0.04%
1
0.99%
bart van assche
bart van assche
1
0.04%
1
0.99%
martin k. petersen
martin k. petersen
1
0.04%
1
0.99%
alexey dobriyan
alexey dobriyan
1
0.04%
1
0.99%
kirill a. shutemov
kirill a. shutemov
1
0.04%
1
0.99%
russell king
russell king
1
0.04%
1
0.99%
mikulas patocka
mikulas patocka
1
0.04%
1
0.99%
akinobu mita
akinobu mita
1
0.04%
1
0.99%
Total
2607
100.00%
101
100.00%
  
Directory: drivers/block

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