diff --git a/MAINTAINERS b/MAINTAINERS
index a7e6ef3dae165e4d886f7114f66ca46ef7fcc8c5..29f4f4dc1456fec9c1173618ccd2c81ee042e89e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3254,6 +3254,11 @@ W: http://rt2x00.serialmonkey.com/
S: Maintained
F: drivers/net/wireless/rt2x00/
+RAMDISK RAM BLOCK DEVICE DRIVER
+P: Nick Piggin
+M: npiggin@suse.de
+S: Maintained
+
RANDOM NUMBER DRIVER
P: Matt Mackall
M: mpm@selenic.com
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 64e5148d82bc8cce2018012f6bf5587570ba2267..8be67cd3fe01b0635a75cf2ac3c942cda0b2e5a6 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -322,7 +322,7 @@ config BLK_DEV_UB
If unsure, say N.
config BLK_DEV_RAM
- tristate "RAM disk support"
+ tristate "RAM block device support"
---help---
Saying Y here will allow you to use a portion of your RAM memory as
a block device, so that you can make file systems on it, read and
@@ -357,16 +357,6 @@ config BLK_DEV_RAM_SIZE
The default value is 4096 kilobytes. Only change this if you know
what you are doing.
-config BLK_DEV_RAM_BLOCKSIZE
- int "Default RAM disk block size (bytes)"
- depends on BLK_DEV_RAM
- default "1024"
- help
- The default value is 1024 bytes. PAGE_SIZE is a much more
- efficient choice however. The default is kept to ensure initrd
- setups function - apparently needed by the rd_load_image routine
- that supposes the filesystem in the image uses a 1024 blocksize.
-
config CDROM_PKTCDVD
tristate "Packet writing on CD/DVD media"
depends on !UML
diff --git a/drivers/block/Makefile b/drivers/block/Makefile
index 7691505a2e12ee8621d93a5c0b78f3a4b8e6dcc1..01c972415cb29c8ed5fcfae76972d622e4833b0c 100644
--- a/drivers/block/Makefile
+++ b/drivers/block/Makefile
@@ -11,7 +11,7 @@ obj-$(CONFIG_AMIGA_FLOPPY) += amiflop.o
obj-$(CONFIG_PS3_DISK) += ps3disk.o
obj-$(CONFIG_ATARI_FLOPPY) += ataflop.o
obj-$(CONFIG_AMIGA_Z2RAM) += z2ram.o
-obj-$(CONFIG_BLK_DEV_RAM) += rd.o
+obj-$(CONFIG_BLK_DEV_RAM) += brd.o
obj-$(CONFIG_BLK_DEV_LOOP) += loop.o
obj-$(CONFIG_BLK_DEV_PS2) += ps2esdi.o
obj-$(CONFIG_BLK_DEV_XD) += xd.o
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
new file mode 100644
index 0000000000000000000000000000000000000000..50b659bedc8fe57893de5f52635b989037210b3c
--- /dev/null
+++ b/drivers/block/brd.c
@@ -0,0 +1,548 @@
+/*
+ * 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/gfp.h>
+#include <linux/radix-tree.h>
+#include <linux/buffer_head.h> /* invalidate_bh_lrus() */
+
+#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;
+ int brd_refcnt;
+ loff_t brd_offset;
+ loff_t brd_sizelimit;
+ unsigned brd_blocksize;
+
+ 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 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;
+}
+
+/*
+ * 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;
+
+ 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.
+ */
+ page = alloc_page(GFP_NOIO | __GFP_HIGHMEM | __GFP_ZERO);
+ 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;
+ 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);
+ } else
+ page->index = idx;
+ spin_unlock(&brd->brd_lock);
+
+ radix_tree_preload_end();
+
+ return page;
+}
+
+/*
+ * 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);
+}
+
+/*
+ * 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 -ENOMEM;
+ if (copy < n) {
+ sector += copy >> SECTOR_SHIFT;
+ if (!brd_insert_page(brd, sector))
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+/*
+ * 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, KM_USER1);
+ memcpy(dst + offset, src, copy);
+ kunmap_atomic(dst, KM_USER1);
+
+ 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, KM_USER1);
+ memcpy(dst, src, copy);
+ kunmap_atomic(dst, KM_USER1);
+ }
+}
+
+/*
+ * 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, KM_USER1);
+ memcpy(dst, src + offset, copy);
+ kunmap_atomic(src, KM_USER1);
+ } 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, KM_USER1);
+ memcpy(dst, src, copy);
+ kunmap_atomic(src, KM_USER1);
+ } else
+ memset(dst, 0, copy);
+ }
+}
+
+/*
+ * 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, KM_USER0);
+ if (rw == READ) {
+ copy_from_brd(mem + off, brd, sector, len);
+ flush_dcache_page(page);
+ } else
+ copy_to_brd(brd, mem + off, sector, len);
+ kunmap_atomic(mem, KM_USER0);
+
+out:
+ return err;
+}
+
+static int 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;
+ int i;
+ int err = -EIO;
+
+ sector = bio->bi_sector;
+ if (sector + (bio->bi_size >> SECTOR_SHIFT) >
+ get_capacity(bdev->bd_disk))
+ goto out;
+
+ rw = bio_rw(bio);
+ if (rw == READA)
+ rw = READ;
+
+ bio_for_each_segment(bvec, bio, i) {
+ unsigned int len = bvec->bv_len;
+ err = brd_do_bvec(brd, bvec->bv_page, len,
+ bvec->bv_offset, rw, sector);
+ if (err)
+ break;
+ sector += len >> SECTOR_SHIFT;
+ }
+
+out:
+ bio_endio(bio, err);
+
+ return 0;
+}
+
+static int brd_ioctl(struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int error;
+ struct block_device *bdev = inode->i_bdev;
+ 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(&bdev->bd_mutex);
+ error = -EBUSY;
+ if (bdev->bd_openers <= 1) {
+ /*
+ * Invalidate 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.
+ */
+ invalidate_bh_lrus();
+ truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
+ brd_free_pages(brd);
+ error = 0;
+ }
+ mutex_unlock(&bdev->bd_mutex);
+
+ return error;
+}
+
+static struct block_device_operations brd_fops = {
+ .owner = THIS_MODULE,
+ .ioctl = brd_ioctl,
+};
+
+/*
+ * And now the modules code and kernel interface.
+ */
+static int rd_nr;
+int rd_size = CONFIG_BLK_DEV_RAM_SIZE;
+module_param(rd_nr, int, 0);
+MODULE_PARM_DESC(rd_nr, "Maximum number of brd devices");
+module_param(rd_size, int, 0);
+MODULE_PARM_DESC(rd_size, "Size of each RAM disk in kbytes.");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_BLOCKDEV_MAJOR(RAMDISK_MAJOR);
+
+#ifndef MODULE
+/* Legacy boot options - nonmodular */
+static int __init ramdisk_size(char *str)
+{
+ rd_size = simple_strtol(str, NULL, 0);
+ return 1;
+}
+static int __init ramdisk_size2(char *str)
+{
+ return ramdisk_size(str);
+}
+__setup("ramdisk=", ramdisk_size);
+__setup("ramdisk_size=", ramdisk_size2);
+#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_sectors(brd->brd_queue, 1024);
+ blk_queue_bounce_limit(brd->brd_queue, BLK_BOUNCE_ANY);
+
+ disk = brd->brd_disk = alloc_disk(1);
+ if (!disk)
+ goto out_free_queue;
+ disk->major = RAMDISK_MAJOR;
+ disk->first_minor = i;
+ disk->fops = &brd_fops;
+ disk->private_data = brd;
+ disk->queue = brd->brd_queue;
+ 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;
+}
+
+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);
+}
+
+static struct brd_device *brd_init_one(int i)
+{
+ struct brd_device *brd;
+
+ 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);
+ }
+out:
+ return brd;
+}
+
+static void brd_del_one(struct brd_device *brd)
+{
+ list_del(&brd->brd_list);
+ del_gendisk(brd->brd_disk);
+ brd_free(brd);
+}
+
+static struct kobject *brd_probe(dev_t dev, int *part, void *data)
+{
+ struct brd_device *brd;
+ struct kobject *kobj;
+
+ mutex_lock(&brd_devices_mutex);
+ brd = brd_init_one(dev & MINORMASK);
+ kobj = brd ? get_disk(brd->brd_disk) : ERR_PTR(-ENOMEM);
+ mutex_unlock(&brd_devices_mutex);
+
+ *part = 0;
+ return kobj;
+}
+
+static int __init brd_init(void)
+{
+ int i, nr;
+ unsigned long range;
+ struct brd_device *brd, *next;
+
+ /*
+ * brd module now has a feature to instantiate underlying device
+ * structure on-demand, provided that there is an access dev node.
+ * However, this will not work well with user space tool that doesn't
+ * know about such "feature". In order to not break any existing
+ * tool, we do the following:
+ *
+ * (1) if rd_nr is specified, create that many upfront, and this
+ * also becomes a hard limit.
+ * (2) if rd_nr is not specified, create 1 rd device on module
+ * load, user can further extend brd device by create dev node
+ * themselves and have kernel automatically instantiate actual
+ * device on-demand.
+ */
+ if (rd_nr > 1UL << MINORBITS)
+ return -EINVAL;
+
+ if (rd_nr) {
+ nr = rd_nr;
+ range = rd_nr;
+ } else {
+ nr = CONFIG_BLK_DEV_RAM_COUNT;
+ range = 1UL << MINORBITS;
+ }
+
+ if (register_blkdev(RAMDISK_MAJOR, "ramdisk"))
+ return -EIO;
+
+ for (i = 0; i < 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), range,
+ THIS_MODULE, brd_probe, NULL, NULL);
+
+ printk(KERN_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, "brd");
+ return -ENOMEM;
+}
+
+static void __exit brd_exit(void)
+{
+ unsigned long range;
+ struct brd_device *brd, *next;
+
+ range = rd_nr ? rd_nr : 1UL << MINORBITS;
+
+ list_for_each_entry_safe(brd, next, &brd_devices, brd_list)
+ brd_del_one(brd);
+
+ blk_unregister_region(MKDEV(RAMDISK_MAJOR, 0), range);
+ unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
+}
+
+module_init(brd_init);
+module_exit(brd_exit);
+
diff --git a/drivers/block/rd.c b/drivers/block/rd.c
deleted file mode 100644
index 06e23be70904423afc8e6646832eeda664aa5484..0000000000000000000000000000000000000000
--- a/drivers/block/rd.c
+++ /dev/null
@@ -1,537 +0,0 @@
-/*
- * ramdisk.c - Multiple RAM disk driver - gzip-loading version - v. 0.8 beta.
- *
- * (C) Chad Page, Theodore Ts'o, et. al, 1995.
- *
- * This RAM disk is designed to have filesystems created on it and mounted
- * just like a regular floppy disk.
- *
- * It also does something suggested by Linus: use the buffer cache as the
- * RAM disk data. This makes it possible to dynamically allocate the RAM disk
- * buffer - with some consequences I have to deal with as I write this.
- *
- * This code is based on the original ramdisk.c, written mostly by
- * Theodore Ts'o (TYT) in 1991. The code was largely rewritten by
- * Chad Page to use the buffer cache to store the RAM disk data in
- * 1995; Theodore then took over the driver again, and cleaned it up
- * for inclusion in the mainline kernel.
- *
- * The original CRAMDISK code was written by Richard Lyons, and
- * adapted by Chad Page to use the new RAM disk interface. Theodore
- * Ts'o rewrote it so that both the compressed RAM disk loader and the
- * kernel decompressor uses the same inflate.c codebase. The RAM disk
- * loader now also loads into a dynamic (buffer cache based) RAM disk,
- * not the old static RAM disk. Support for the old static RAM disk has
- * been completely removed.
- *
- * Loadable module support added by Tom Dyas.
- *
- * Further cleanups by Chad Page (page0588@sundance.sjsu.edu):
- * Cosmetic changes in #ifdef MODULE, code movement, etc.
- * When the RAM disk module is removed, free the protected buffers
- * Default RAM disk size changed to 2.88 MB
- *
- * Added initrd: Werner Almesberger & Hans Lermen, Feb '96
- *
- * 4/25/96 : Made RAM disk size a parameter (default is now 4 MB)
- * - Chad Page
- *
- * Add support for fs images split across >1 disk, Paul Gortmaker, Mar '98
- *
- * Make block size and block size shift for RAM disks a global macro
- * and set blk_size for -ENOSPC, Werner Fink <werner@suse.de>, Apr '99
- */
-
-#include <linux/string.h>
-#include <linux/slab.h>
-#include <asm/atomic.h>
-#include <linux/bio.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/init.h>
-#include <linux/pagemap.h>
-#include <linux/blkdev.h>
-#include <linux/genhd.h>
-#include <linux/buffer_head.h> /* for invalidate_bdev() */
-#include <linux/backing-dev.h>
-#include <linux/blkpg.h>
-#include <linux/writeback.h>
-#include <linux/log2.h>
-
-#include <asm/uaccess.h>
-
-/* Various static variables go here. Most are used only in the RAM disk code.
- */
-
-static struct gendisk *rd_disks[CONFIG_BLK_DEV_RAM_COUNT];
-static struct block_device *rd_bdev[CONFIG_BLK_DEV_RAM_COUNT];/* Protected device data */
-static struct request_queue *rd_queue[CONFIG_BLK_DEV_RAM_COUNT];
-
-/*
- * Parameters for the boot-loading of the RAM disk. These are set by
- * init/main.c (from arguments to the kernel command line) or from the
- * architecture-specific setup routine (from the stored boot sector
- * information).
- */
-int rd_size = CONFIG_BLK_DEV_RAM_SIZE; /* Size of the RAM disks */
-/*
- * It would be very desirable to have a soft-blocksize (that in the case
- * of the ramdisk driver is also the hardblocksize ;) of PAGE_SIZE because
- * doing that we'll achieve a far better MM footprint. Using a rd_blocksize of
- * BLOCK_SIZE in the worst case we'll make PAGE_SIZE/BLOCK_SIZE buffer-pages
- * unfreeable. With a rd_blocksize of PAGE_SIZE instead we are sure that only
- * 1 page will be protected. Depending on the size of the ramdisk you
- * may want to change the ramdisk blocksize to achieve a better or worse MM
- * behaviour. The default is still BLOCK_SIZE (needed by rd_load_image that
- * supposes the filesystem in the image uses a BLOCK_SIZE blocksize).
- */
-static int rd_blocksize = CONFIG_BLK_DEV_RAM_BLOCKSIZE;
-
-/*
- * Copyright (C) 2000 Linus Torvalds.
- * 2000 Transmeta Corp.
- * aops copied from ramfs.
- */
-
-/*
- * If a ramdisk page has buffers, some may be uptodate and some may be not.
- * To bring the page uptodate we zero out the non-uptodate buffers. The
- * page must be locked.
- */
-static void make_page_uptodate(struct page *page)
-{
- if (page_has_buffers(page)) {
- struct buffer_head *bh = page_buffers(page);
- struct buffer_head *head = bh;
-
- do {
- if (!buffer_uptodate(bh)) {
- memset(bh->b_data, 0, bh->b_size);
- /*
- * akpm: I'm totally undecided about this. The
- * buffer has just been magically brought "up to
- * date", but nobody should want to be reading
- * it anyway, because it hasn't been used for
- * anything yet. It is still in a "not read
- * from disk yet" state.
- *
- * But non-uptodate buffers against an uptodate
- * page are against the rules. So do it anyway.
- */
- set_buffer_uptodate(bh);
- }
- } while ((bh = bh->b_this_page) != head);
- } else {
- memset(page_address(page), 0, PAGE_CACHE_SIZE);
- }
- flush_dcache_page(page);
- SetPageUptodate(page);
-}
-
-static int ramdisk_readpage(struct file *file, struct page *page)
-{
- if (!PageUptodate(page))
- make_page_uptodate(page);
- unlock_page(page);
- return 0;
-}
-
-static int ramdisk_prepare_write(struct file *file, struct page *page,
- unsigned offset, unsigned to)
-{
- if (!PageUptodate(page))
- make_page_uptodate(page);
- return 0;
-}
-
-static int ramdisk_commit_write(struct file *file, struct page *page,
- unsigned offset, unsigned to)
-{
- set_page_dirty(page);
- return 0;
-}
-
-/*
- * ->writepage to the blockdev's mapping has to redirty the page so that the
- * VM doesn't go and steal it. We return AOP_WRITEPAGE_ACTIVATE so that the VM
- * won't try to (pointlessly) write the page again for a while.
- *
- * Really, these pages should not be on the LRU at all.
- */
-static int ramdisk_writepage(struct page *page, struct writeback_control *wbc)
-{
- if (!PageUptodate(page))
- make_page_uptodate(page);
- SetPageDirty(page);
- if (wbc->for_reclaim)
- return AOP_WRITEPAGE_ACTIVATE;
- unlock_page(page);
- return 0;
-}
-
-/*
- * This is a little speedup thing: short-circuit attempts to write back the
- * ramdisk blockdev inode to its non-existent backing store.
- */
-static int ramdisk_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
-{
- return 0;
-}
-
-/*
- * ramdisk blockdev pages have their own ->set_page_dirty() because we don't
- * want them to contribute to dirty memory accounting.
- */
-static int ramdisk_set_page_dirty(struct page *page)
-{
- if (!TestSetPageDirty(page))
- return 1;
- return 0;
-}
-
-/*
- * releasepage is called by pagevec_strip/try_to_release_page if
- * buffers_heads_over_limit is true. Without a releasepage function
- * try_to_free_buffers is called instead. That can unset the dirty
- * bit of our ram disk pages, which will be eventually freed, even
- * if the page is still in use.
- */
-static int ramdisk_releasepage(struct page *page, gfp_t dummy)
-{
- return 0;
-}
-
-static const struct address_space_operations ramdisk_aops = {
- .readpage = ramdisk_readpage,
- .prepare_write = ramdisk_prepare_write,
- .commit_write = ramdisk_commit_write,
- .writepage = ramdisk_writepage,
- .set_page_dirty = ramdisk_set_page_dirty,
- .writepages = ramdisk_writepages,
- .releasepage = ramdisk_releasepage,
-};
-
-static int rd_blkdev_pagecache_IO(int rw, struct bio_vec *vec, sector_t sector,
- struct address_space *mapping)
-{
- pgoff_t index = sector >> (PAGE_CACHE_SHIFT - 9);
- unsigned int vec_offset = vec->bv_offset;
- int offset = (sector << 9) & ~PAGE_CACHE_MASK;
- int size = vec->bv_len;
- int err = 0;
-
- do {
- int count;
- struct page *page;
- char *src;
- char *dst;
-
- count = PAGE_CACHE_SIZE - offset;
- if (count > size)
- count = size;
- size -= count;
-
- page = grab_cache_page(mapping, index);
- if (!page) {
- err = -ENOMEM;
- goto out;
- }
-
- if (!PageUptodate(page))
- make_page_uptodate(page);
-
- index++;
-
- if (rw == READ) {
- src = kmap_atomic(page, KM_USER0) + offset;
- dst = kmap_atomic(vec->bv_page, KM_USER1) + vec_offset;
- } else {
- src = kmap_atomic(vec->bv_page, KM_USER0) + vec_offset;
- dst = kmap_atomic(page, KM_USER1) + offset;
- }
- offset = 0;
- vec_offset += count;
-
- memcpy(dst, src, count);
-
- kunmap_atomic(src, KM_USER0);
- kunmap_atomic(dst, KM_USER1);
-
- if (rw == READ)
- flush_dcache_page(vec->bv_page);
- else
- set_page_dirty(page);
- unlock_page(page);
- put_page(page);
- } while (size);
-
- out:
- return err;
-}
-
-/*
- * Basically, my strategy here is to set up a buffer-head which can't be
- * deleted, and make that my Ramdisk. If the request is outside of the
- * allocated size, we must get rid of it...
- *
- * 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Added devfs support
- *
- */
-static int rd_make_request(struct request_queue *q, struct bio *bio)
-{
- struct block_device *bdev = bio->bi_bdev;
- struct address_space * mapping = bdev->bd_inode->i_mapping;
- sector_t sector = bio->bi_sector;
- unsigned long len = bio->bi_size >> 9;
- int rw = bio_data_dir(bio);
- struct bio_vec *bvec;
- int ret = 0, i;
-
- if (sector + len > get_capacity(bdev->bd_disk))
- goto fail;
-
- if (rw==READA)
- rw=READ;
-
- bio_for_each_segment(bvec, bio, i) {
- ret |= rd_blkdev_pagecache_IO(rw, bvec, sector, mapping);
- sector += bvec->bv_len >> 9;
- }
- if (ret)
- goto fail;
-
- bio_endio(bio, 0);
- return 0;
-fail:
- bio_io_error(bio);
- return 0;
-}
-
-static int rd_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- int error;
- struct block_device *bdev = inode->i_bdev;
-
- if (cmd != BLKFLSBUF)
- return -ENOTTY;
-
- /*
- * special: we want to release the ramdisk memory, it's not like with
- * the other blockdevices where this ioctl only flushes away the buffer
- * cache
- */
- error = -EBUSY;
- mutex_lock(&bdev->bd_mutex);
- if (bdev->bd_openers <= 2) {
- truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
- error = 0;
- }
- mutex_unlock(&bdev->bd_mutex);
- return error;
-}
-
-/*
- * This is the backing_dev_info for the blockdev inode itself. It doesn't need
- * writeback and it does not contribute to dirty memory accounting.
- */
-static struct backing_dev_info rd_backing_dev_info = {
- .ra_pages = 0, /* No readahead */
- .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK | BDI_CAP_MAP_COPY,
- .unplug_io_fn = default_unplug_io_fn,
-};
-
-/*
- * This is the backing_dev_info for the files which live atop the ramdisk
- * "device". These files do need writeback and they do contribute to dirty
- * memory accounting.
- */
-static struct backing_dev_info rd_file_backing_dev_info = {
- .ra_pages = 0, /* No readahead */
- .capabilities = BDI_CAP_MAP_COPY, /* Does contribute to dirty memory */
- .unplug_io_fn = default_unplug_io_fn,
-};
-
-static int rd_open(struct inode *inode, struct file *filp)
-{
- unsigned unit = iminor(inode);
-
- if (rd_bdev[unit] == NULL) {
- struct block_device *bdev = inode->i_bdev;
- struct address_space *mapping;
- unsigned bsize;
- gfp_t gfp_mask;
-
- inode = igrab(bdev->bd_inode);
- rd_bdev[unit] = bdev;
- bdev->bd_openers++;
- bsize = bdev_hardsect_size(bdev);
- bdev->bd_block_size = bsize;
- inode->i_blkbits = blksize_bits(bsize);
- inode->i_size = get_capacity(bdev->bd_disk)<<9;
-
- mapping = inode->i_mapping;
- mapping->a_ops = &ramdisk_aops;
- mapping->backing_dev_info = &rd_backing_dev_info;
- bdev->bd_inode_backing_dev_info = &rd_file_backing_dev_info;
-
- /*
- * Deep badness. rd_blkdev_pagecache_IO() needs to allocate
- * pagecache pages within a request_fn. We cannot recur back
- * into the filesystem which is mounted atop the ramdisk, because
- * that would deadlock on fs locks. And we really don't want
- * to reenter rd_blkdev_pagecache_IO when we're already within
- * that function.
- *
- * So we turn off __GFP_FS and __GFP_IO.
- *
- * And to give this thing a hope of working, turn on __GFP_HIGH.
- * Hopefully, there's enough regular memory allocation going on
- * for the page allocator emergency pools to keep the ramdisk
- * driver happy.
- */
- gfp_mask = mapping_gfp_mask(mapping);
- gfp_mask &= ~(__GFP_FS|__GFP_IO);
- gfp_mask |= __GFP_HIGH;
- mapping_set_gfp_mask(mapping, gfp_mask);
- }
-
- return 0;
-}
-
-static struct block_device_operations rd_bd_op = {
- .owner = THIS_MODULE,
- .open = rd_open,
- .ioctl = rd_ioctl,
-};
-
-/*
- * Before freeing the module, invalidate all of the protected buffers!
- */
-static void __exit rd_cleanup(void)
-{
- int i;
-
- for (i = 0; i < CONFIG_BLK_DEV_RAM_COUNT; i++) {
- struct block_device *bdev = rd_bdev[i];
- rd_bdev[i] = NULL;
- if (bdev) {
- invalidate_bdev(bdev);
- blkdev_put(bdev);
- }
- del_gendisk(rd_disks[i]);
- put_disk(rd_disks[i]);
- blk_cleanup_queue(rd_queue[i]);
- }
- unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
-
- bdi_destroy(&rd_file_backing_dev_info);
- bdi_destroy(&rd_backing_dev_info);
-}
-
-/*
- * This is the registration and initialization section of the RAM disk driver
- */
-static int __init rd_init(void)
-{
- int i;
- int err;
-
- err = bdi_init(&rd_backing_dev_info);
- if (err)
- goto out2;
-
- err = bdi_init(&rd_file_backing_dev_info);
- if (err) {
- bdi_destroy(&rd_backing_dev_info);
- goto out2;
- }
-
- err = -ENOMEM;
-
- if (rd_blocksize > PAGE_SIZE || rd_blocksize < 512 ||
- !is_power_of_2(rd_blocksize)) {
- printk("RAMDISK: wrong blocksize %d, reverting to defaults\n",
- rd_blocksize);
- rd_blocksize = BLOCK_SIZE;
- }
-
- for (i = 0; i < CONFIG_BLK_DEV_RAM_COUNT; i++) {
- rd_disks[i] = alloc_disk(1);
- if (!rd_disks[i])
- goto out;
-
- rd_queue[i] = blk_alloc_queue(GFP_KERNEL);
- if (!rd_queue[i]) {
- put_disk(rd_disks[i]);
- goto out;
- }
- }
-
- if (register_blkdev(RAMDISK_MAJOR, "ramdisk")) {
- err = -EIO;
- goto out;
- }
-
- for (i = 0; i < CONFIG_BLK_DEV_RAM_COUNT; i++) {
- struct gendisk *disk = rd_disks[i];
-
- blk_queue_make_request(rd_queue[i], &rd_make_request);
- blk_queue_hardsect_size(rd_queue[i], rd_blocksize);
-
- /* rd_size is given in kB */
- disk->major = RAMDISK_MAJOR;
- disk->first_minor = i;
- disk->fops = &rd_bd_op;
- disk->queue = rd_queue[i];
- disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
- sprintf(disk->disk_name, "ram%d", i);
- set_capacity(disk, rd_size * 2);
- add_disk(rd_disks[i]);
- }
-
- /* rd_size is given in kB */
- printk("RAMDISK driver initialized: "
- "%d RAM disks of %dK size %d blocksize\n",
- CONFIG_BLK_DEV_RAM_COUNT, rd_size, rd_blocksize);
-
- return 0;
-out:
- while (i--) {
- put_disk(rd_disks[i]);
- blk_cleanup_queue(rd_queue[i]);
- }
- bdi_destroy(&rd_backing_dev_info);
- bdi_destroy(&rd_file_backing_dev_info);
-out2:
- return err;
-}
-
-module_init(rd_init);
-module_exit(rd_cleanup);
-
-/* options - nonmodular */
-#ifndef MODULE
-static int __init ramdisk_size(char *str)
-{
- rd_size = simple_strtol(str,NULL,0);
- return 1;
-}
-static int __init ramdisk_blocksize(char *str)
-{
- rd_blocksize = simple_strtol(str,NULL,0);
- return 1;
-}
-__setup("ramdisk_size=", ramdisk_size);
-__setup("ramdisk_blocksize=", ramdisk_blocksize);
-#endif
-
-/* options - modular */
-module_param(rd_size, int, 0);
-MODULE_PARM_DESC(rd_size, "Size of each RAM disk in kbytes.");
-module_param(rd_blocksize, int, 0);
-MODULE_PARM_DESC(rd_blocksize, "Blocksize of each RAM disk in bytes.");
-MODULE_ALIAS_BLOCKDEV_MAJOR(RAMDISK_MAJOR);
-
-MODULE_LICENSE("GPL");
diff --git a/fs/buffer.c b/fs/buffer.c
index 826baf4f04bc738fdfea27f6652bc3c0bfe9969d..11b002e01d6e4a24a90d0f74d0e3d032333f0bec 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1436,6 +1436,7 @@ void invalidate_bh_lrus(void)
{
on_each_cpu(invalidate_bh_lru, NULL, 1, 1);
}
+EXPORT_SYMBOL_GPL(invalidate_bh_lrus);
void set_bh_page(struct buffer_head *bh,
struct page *page, unsigned long offset)