Jens Axboe wrote:
> On Tue, Jul 16 2002, Rik van Riel wrote:
> > On Tue, 16 Jul 2002, Jens Axboe wrote:
> > > On Tue, Jul 16 2002, Rik van Riel wrote:
> > > Given the finite size of the pool and the possibly infinite stacking
> > > level, yes that is possible. You may just run out of loop minors before
> > > this happens [1]. Also note that you need more than a simple remapping,
> > > crypto setup for instance.
> >
> > Or maybe SMP, with multiple CPUs submitting requests at the
> > same time ?
>
> It would still require a totally pathetic loop setup. More than 2 or 3
> stacked loop devices that are not using remapping would crawl
remapping?
> performance wise. Now make that eg 32 "indirections" (allocations and
> copies on _each_ i/o), and I think you'll find that the system would be
> impossible to use long before this theoretical dead lock would be hit.
Jens,
Your remapping code has _never_ worked. This is because your remapping is
supposedly enabled in none_status(), but init hook of type 0 transfer is
never called (check the code in loop_init_xfer). And, even if were enabled,
you would quickly notice that lo->lo_pending count is never decremented in
your 'remap' code.
The patch below fixes that remap issue, plus uncounted number of other loop
issues. For example, device backed loops use pre-allocated pages for zero VM
pressure.
Too bad you seem to be filtering my emails.
Regards,
Jari Ruusu <jari.ruusu@pp.inet.fi>
diff -urN linux-2.5.25/drivers/block/loop.c linux-2.5.25-loopfix/drivers/block/loop.c
--- linux-2.5.25/drivers/block/loop.c Wed Jun 19 12:14:13 2002
+++ linux-2.5.25-loopfix/drivers/block/loop.c Wed Jul 10 22:59:10 2002
@@ -52,6 +52,22 @@
* problem above. Encryption modules that used to rely on the old scheme
* should just call ->i_mapping->bmap() to calculate the physical block
* number.
+ *
+ * IV is now passed as (512 byte) sector number.
+ * Jari Ruusu <jari.ruusu@pp.inet.fi>, May 18 2001
+ *
+ * External encryption module locking bug fixed.
+ * Ingo Rohloff <rohloff@in.tum.de>, June 21 2001
+ *
+ * Make device backed loop work with swap (pre-allocated buffers + queue rewrite).
+ * Jari Ruusu <jari.ruusu@pp.inet.fi>, September 2 2001
+ *
+ * Ported 'pre-allocated buffers + queue rewrite' to BIO for 2.5 kernels
+ * Ben Slusky <sluskyb@stwing.org>, March 1 2002
+ * Jari Ruusu <jari.ruusu@pp.inet.fi>, March 27 2002
+ *
+ * File backed code now uses file->f_op->read/write. Based on Andrew Morton's idea.
+ * Jari Ruusu <jari.ruusu@pp.inet.fi>, May 23 2002
*/
#include <linux/config.h>
@@ -82,14 +98,14 @@
static int max_loop = 8;
static struct loop_device *loop_dev;
-static int *loop_sizes;
+static /*FIXME sector_t*/int *loop_sizes;
static devfs_handle_t devfs_handle; /* For the directory */
/*
* Transfer functions
*/
static int transfer_none(struct loop_device *lo, int cmd, char *raw_buf,
- char *loop_buf, int size, int real_block)
+ char *loop_buf, int size, /*FIXME sector_t*/int real_block)
{
if (raw_buf != loop_buf) {
if (cmd == READ)
@@ -97,12 +113,12 @@
else
memcpy(raw_buf, loop_buf, size);
}
-
+ cond_resched();
return 0;
}
static int transfer_xor(struct loop_device *lo, int cmd, char *raw_buf,
- char *loop_buf, int size, int real_block)
+ char *loop_buf, int size, /*FIXME sector_t*/int real_block)
{
char *in, *out, *key;
int i, keysize;
@@ -119,12 +135,12 @@
keysize = lo->lo_encrypt_key_size;
for (i = 0; i < size; i++)
*out++ = *in++ ^ key[(i & 511) % keysize];
+ cond_resched();
return 0;
}
static int none_status(struct loop_device *lo, struct loop_info *info)
{
- lo->lo_flags |= LO_FLAGS_BH_REMAP;
return 0;
}
@@ -153,353 +169,429 @@
&xor_funcs
};
-#define MAX_DISK_SIZE 1024*1024*1024
-
-static unsigned long
-compute_loop_size(struct loop_device *lo, struct dentry * lo_dentry)
-{
- loff_t size = lo_dentry->d_inode->i_mapping->host->i_size;
- return (size - lo->lo_offset) >> BLOCK_SIZE_BITS;
+/*
+ * First number of 'lo_prealloc' is the default number of RAM pages
+ * to pre-allocate for each device backed loop. Every (configured)
+ * device backed loop pre-allocates this amount of RAM pages unless
+ * later 'lo_prealloc' numbers provide an override. 'lo_prealloc'
+ * overrides are defined in pairs: loop_index,number_of_pages
+ */
+static int lo_prealloc[9] = { 125, -1, 0, -1, 0, -1, 0, -1, 0 };
+#define LO_PREALLOC_MIN 4 /* minimum user defined pre-allocated RAM pages */
+#define LO_PREALLOC_MAX 512 /* maximum user defined pre-allocated RAM pages */
+
+#ifdef MODULE
+MODULE_PARM(lo_prealloc, "1-9i");
+MODULE_PARM_DESC(lo_prealloc, "Number of pre-allocated pages [,index,pages]...");
+#else
+static int __init lo_prealloc_setup(char *str)
+{
+ int x, y, z;
+
+ for (x = 0; x < (sizeof(lo_prealloc) / sizeof(int)); x++) {
+ z = get_option(&str, &y);
+ if (z > 0)
+ lo_prealloc[x] = y;
+ if (z < 2)
+ break;
+ }
+ return 1;
}
+__setup("lo_prealloc=", lo_prealloc_setup);
+#endif
-static void figure_loop_size(struct loop_device *lo)
-{
- loop_sizes[lo->lo_number] = compute_loop_size(lo,
- lo->lo_backing_file->f_dentry);
-
-}
+struct loop_bio_extension {
+ struct bio *bioext_merge;
+ struct loop_device *bioext_loop;
+ sector_t bioext_sector;
+ int bioext_index;
+ int bioext_size;
+};
-static inline int lo_do_transfer(struct loop_device *lo, int cmd, char *rbuf,
- char *lbuf, int size, int rblock)
+static void loop_prealloc_cleanup(struct loop_device *lo)
{
- if (!lo->transfer)
- return 0;
+ struct bio *bio;
- return lo->transfer(lo, cmd, rbuf, lbuf, size, rblock);
+ while ((bio = lo->lo_bio_free0)) {
+ lo->lo_bio_free0 = bio->bi_next;
+ __free_page(bio->bi_io_vec[0].bv_page);
+ kfree(bio->bi_private);
+ bio->bi_next = NULL;
+ bio_put(bio);
+ }
+ while ((bio = lo->lo_bio_free1)) {
+ lo->lo_bio_free1 = bio->bi_next;
+ /* bi_flags was used for other purpose */
+ bio->bi_flags = 0;
+ /* bi_cnt was used for other purpose */
+ atomic_set(&bio->bi_cnt, 1);
+ bio->bi_next = NULL;
+ bio_put(bio);
+ }
}
-static int
-do_lo_send(struct loop_device *lo, struct bio_vec *bvec, int bsize, loff_t pos)
+static int loop_prealloc_init(struct loop_device *lo, int y)
{
- struct file *file = lo->lo_backing_file; /* kudos to NFsckingS */
- struct address_space *mapping = file->f_dentry->d_inode->i_mapping;
- struct address_space_operations *aops = mapping->a_ops;
- struct page *page;
- char *kaddr, *data;
- unsigned long index;
- unsigned size, offset;
- int len;
- int ret = 0;
+ struct bio *bio;
+ int x;
- down(&mapping->host->i_sem);
- index = pos >> PAGE_CACHE_SHIFT;
- offset = pos & (PAGE_CACHE_SIZE - 1);
- data = kmap(bvec->bv_page) + bvec->bv_offset;
- len = bvec->bv_len;
- while (len > 0) {
- int IV = index * (PAGE_CACHE_SIZE/bsize) + offset/bsize;
- int transfer_result;
-
- size = PAGE_CACHE_SIZE - offset;
- if (size > len)
- size = len;
-
- page = grab_cache_page(mapping, index);
- if (!page)
- goto fail;
- if (aops->prepare_write(file, page, offset, offset+size))
- goto unlock;
- kaddr = page_address(page);
- flush_dcache_page(page);
- transfer_result = lo_do_transfer(lo, WRITE, kaddr + offset, data, size, IV);
- if (transfer_result) {
- /*
- * The transfer failed, but we still write the data to
- * keep prepare/commit calls balanced.
- */
- printk(KERN_ERR "loop: transfer error block %ld\n", index);
- memset(kaddr + offset, 0, size);
- }
- if (aops->commit_write(file, page, offset, offset+size))
- goto unlock;
- if (transfer_result)
- goto unlock;
- data += size;
- len -= size;
- offset = 0;
- index++;
- pos += size;
- unlock_page(page);
- page_cache_release(page);
+ if(!y) {
+ y = lo_prealloc[0];
+ for (x = 1; x < (sizeof(lo_prealloc) / sizeof(int)); x += 2) {
+ if (lo_prealloc[x + 1] && (lo->lo_number == lo_prealloc[x])) {
+ y = lo_prealloc[x + 1];
+ break;
+ }
+ }
}
- up(&mapping->host->i_sem);
-out:
- kunmap(bvec->bv_page);
- return ret;
+ lo->lo_bio_flsh = (y * 3) / 4;
-unlock:
- unlock_page(page);
- page_cache_release(page);
-fail:
- up(&mapping->host->i_sem);
- ret = -1;
- goto out;
+ for (x = 0; x < y; x++) {
+ bio = bio_alloc(GFP_KERNEL, 1);
+ if (!bio) {
+ fail1:
+ loop_prealloc_cleanup(lo);
+ return 1;
+ }
+ bio->bi_io_vec[0].bv_page = alloc_page(GFP_KERNEL);
+ if (!bio->bi_io_vec[0].bv_page) {
+ fail2:
+ bio->bi_next = NULL;
+ bio_put(bio);
+ goto fail1;
+ }
+ bio->bi_vcnt = 1;
+ bio->bi_private = kmalloc(sizeof(struct loop_bio_extension), GFP_KERNEL);
+ if (!bio->bi_private)
+ goto fail2;
+ bio->bi_next = lo->lo_bio_free0;
+ lo->lo_bio_free0 = bio;
+
+ bio = bio_alloc(GFP_KERNEL, 1);
+ if (!bio)
+ goto fail1;
+ bio->bi_vcnt = 1;
+ bio->bi_next = lo->lo_bio_free1;
+ lo->lo_bio_free1 = bio;
+ }
+ return 0;
}
-static int
-lo_send(struct loop_device *lo, struct bio *bio, int bsize, loff_t pos)
+static void loop_add_queue_last(struct loop_device *lo, struct bio *bio, struct bio **q)
{
- unsigned vecnr;
- int ret = 0;
-
- for (vecnr = 0; vecnr < bio->bi_vcnt; vecnr++) {
- struct bio_vec *bvec = &bio->bi_io_vec[vecnr];
+ unsigned long flags;
- ret = do_lo_send(lo, bvec, bsize, pos);
- if (ret < 0)
- break;
- pos += bvec->bv_len;
+ spin_lock_irqsave(&lo->lo_lock, flags);
+ if (*q) {
+ bio->bi_next = (*q)->bi_next;
+ (*q)->bi_next = bio;
+ } else {
+ bio->bi_next = bio;
}
- return ret;
-}
+ *q = bio;
+ spin_unlock_irqrestore(&lo->lo_lock, flags);
-struct lo_read_data {
- struct loop_device *lo;
- char *data;
- int bsize;
-};
+ if (waitqueue_active(&lo->lo_bio_wait))
+ wake_up_interruptible(&lo->lo_bio_wait);
+}
-static int lo_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size)
+static void loop_add_queue_first(struct loop_device *lo, struct bio *bio, struct bio **q)
{
- char *kaddr;
- unsigned long count = desc->count;
- struct lo_read_data *p = (struct lo_read_data*)desc->buf;
- struct loop_device *lo = p->lo;
- int IV = page->index * (PAGE_CACHE_SIZE/p->bsize) + offset/p->bsize;
-
- if (size > count)
- size = count;
-
- kaddr = kmap(page);
- if (lo_do_transfer(lo, READ, kaddr + offset, p->data, size, IV)) {
- size = 0;
- printk(KERN_ERR "loop: transfer error block %ld\n",page->index);
- desc->error = -EINVAL;
- }
- kunmap(page);
-
- desc->count = count - size;
- desc->written += size;
- p->data += size;
- return size;
-}
-
-static int
-do_lo_receive(struct loop_device *lo,
- struct bio_vec *bvec, int bsize, loff_t pos)
-{
- struct lo_read_data cookie;
- read_descriptor_t desc;
- struct file *file;
-
- cookie.lo = lo;
- cookie.data = kmap(bvec->bv_page) + bvec->bv_offset;
- cookie.bsize = bsize;
- desc.written = 0;
- desc.count = bvec->bv_len;
- desc.buf = (char*)&cookie;
- desc.error = 0;
spin_lock_irq(&lo->lo_lock);
- file = lo->lo_backing_file;
+ if (*q) {
+ bio->bi_next = (*q)->bi_next;
+ (*q)->bi_next = bio;
+ } else {
+ bio->bi_next = bio;
+ *q = bio;
+ }
spin_unlock_irq(&lo->lo_lock);
- do_generic_file_read(file, &pos, &desc, lo_read_actor);
- kunmap(bvec->bv_page);
- return desc.error;
}
-static int
-lo_receive(struct loop_device *lo, struct bio *bio, int bsize, loff_t pos)
+static struct bio *loop_get_bio(struct loop_device *lo, int *list_nr)
{
- unsigned vecnr;
- int ret = 0;
-
- for (vecnr = 0; vecnr < bio->bi_vcnt; vecnr++) {
- struct bio_vec *bvec = &bio->bi_io_vec[vecnr];
+ struct bio *bio = NULL, *last;
- ret = do_lo_receive(lo, bvec, bsize, pos);
- if (ret < 0)
- break;
- pos += bvec->bv_len;
+ spin_lock_irq(&lo->lo_lock);
+ if ((last = lo->lo_bio_que0)) {
+ bio = last->bi_next;
+ if (bio == last)
+ lo->lo_bio_que0 = NULL;
+ else
+ last->bi_next = bio->bi_next;
+ bio->bi_next = NULL;
+ *list_nr = 0;
+ } else if ((last = lo->lo_bio_que1)) {
+ bio = last->bi_next;
+ if (bio == last)
+ lo->lo_bio_que1 = NULL;
+ else
+ last->bi_next = bio->bi_next;
+ bio->bi_next = NULL;
+ *list_nr = 1;
+ } else if ((last = lo->lo_bio_que2)) {
+ bio = last->bi_next;
+ if (bio == last)
+ lo->lo_bio_que2 = NULL;
+ else
+ last->bi_next = bio->bi_next;
+ bio->bi_next = NULL;
+ *list_nr = 2;
}
- return ret;
-}
-
-static inline int loop_get_bs(struct loop_device *lo)
-{
- return block_size(lo->lo_device);
-}
-
-static inline unsigned long loop_get_iv(struct loop_device *lo,
- unsigned long sector)
-{
- int bs = loop_get_bs(lo);
- unsigned long offset, IV;
-
- IV = sector / (bs >> 9) + lo->lo_offset / bs;
- offset = ((sector % (bs >> 9)) << 9) + lo->lo_offset % bs;
- if (offset >= bs)
- IV++;
-
- return IV;
+ spin_unlock_irq(&lo->lo_lock);
+ return bio;
}
-static int do_bio_filebacked(struct loop_device *lo, struct bio *bio)
+static void loop_put_buffer(struct loop_device *lo, struct bio *b, int flist)
{
- loff_t pos;
- int ret;
-
- pos = ((loff_t) bio->bi_sector << 9) + lo->lo_offset;
-
- do {
- if (bio_rw(bio) == WRITE)
- ret = lo_send(lo, bio, loop_get_bs(lo), pos);
- else
- ret = lo_receive(lo, bio, loop_get_bs(lo), pos);
+ unsigned long flags;
+ int wk;
- } while (++bio->bi_idx < bio->bi_vcnt);
+ spin_lock_irqsave(&lo->lo_lock, flags);
+ if(!flist) {
+ b->bi_next = lo->lo_bio_free0;
+ lo->lo_bio_free0 = b;
+ wk = lo->lo_bio_need & 1;
+ } else {
+ b->bi_next = lo->lo_bio_free1;
+ lo->lo_bio_free1 = b;
+ wk = lo->lo_bio_need & 2;
+ }
+ spin_unlock_irqrestore(&lo->lo_lock, flags);
- return ret;
+ if (wk && waitqueue_active(&lo->lo_bio_wait))
+ wake_up_interruptible(&lo->lo_bio_wait);
}
-static void loop_end_io_transfer(struct bio *);
-static void loop_put_buffer(struct bio *bio)
+static void loop_end_io_transfer(struct bio *bio)
{
- /*
- * check bi_end_io, may just be a remapped bio
- */
- if (bio && bio->bi_end_io == loop_end_io_transfer) {
- int i;
- for (i = 0; i < bio->bi_vcnt; i++)
- __free_page(bio->bi_io_vec[i].bv_page);
+ struct loop_bio_extension *extension = bio->bi_private;
+ struct bio *merge = extension->bioext_merge;
+ struct loop_device *lo = extension->bioext_loop;
+ struct bio *origbio = merge->bi_private;
+ int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
- bio_put(bio);
+ if (!uptodate)
+ clear_bit(BIO_UPTODATE, &merge->bi_flags);
+ if (bio_rw(bio) == WRITE) {
+ loop_put_buffer(lo, bio, 0);
+ if (!atomic_dec_and_test(&merge->bi_cnt))
+ return;
+ origbio->bi_next = NULL;
+ bio_endio(origbio, test_bit(BIO_UPTODATE, &merge->bi_flags));
+ loop_put_buffer(lo, merge, 1);
+ if (atomic_dec_and_test(&lo->lo_pending))
+ wake_up_interruptible(&lo->lo_bio_wait);
+ } else {
+ loop_add_queue_last(lo, bio, &lo->lo_bio_que0);
}
}
-/*
- * Add bio to back of pending list
- */
-static void loop_add_bio(struct loop_device *lo, struct bio *bio)
+static struct bio *loop_get_buffer(struct loop_device *lo,
+ struct bio *orig_bio, int from_thread, struct bio **merge_ptr)
{
+ struct bio *bio = NULL, *merge = *merge_ptr;
+ struct loop_bio_extension *extension;
unsigned long flags;
+ int len;
spin_lock_irqsave(&lo->lo_lock, flags);
- if (lo->lo_biotail) {
- lo->lo_biotail->bi_next = bio;
- lo->lo_biotail = bio;
- } else
- lo->lo_bio = lo->lo_biotail = bio;
+ if (!merge) {
+ merge = lo->lo_bio_free1;
+ if (merge) {
+ lo->lo_bio_free1 = merge->bi_next;
+ if (from_thread)
+ lo->lo_bio_need = 0;
+ } else {
+ if (from_thread)
+ lo->lo_bio_need = 2;
+ }
+ }
+ if (merge) {
+ bio = lo->lo_bio_free0;
+ if (bio) {
+ lo->lo_bio_free0 = bio->bi_next;
+ if (from_thread)
+ lo->lo_bio_need = 0;
+ } else {
+ if (from_thread)
+ lo->lo_bio_need = 1;
+ }
+ }
spin_unlock_irqrestore(&lo->lo_lock, flags);
- up(&lo->lo_bh_mutex);
-}
+ if (!(*merge_ptr) && merge) {
+ /*
+ * initialize "merge-bio" which is used as
+ * rendezvous point among multiple vecs
+ */
+ *merge_ptr = merge;
+ merge->bi_sector = orig_bio->bi_sector + (lo->lo_offset >> 9);
+ set_bit(BIO_UPTODATE, &merge->bi_flags);
+ merge->bi_idx = orig_bio->bi_idx;
+ atomic_set(&merge->bi_cnt, orig_bio->bi_vcnt - orig_bio->bi_idx);
+ merge->bi_private = orig_bio;
+ }
-/*
- * Grab first pending buffer
- */
-static struct bio *loop_get_bio(struct loop_device *lo)
-{
- struct bio *bio;
+ if (!bio)
+ return NULL;
- spin_lock_irq(&lo->lo_lock);
- if ((bio = lo->lo_bio)) {
- if (bio == lo->lo_biotail)
- lo->lo_biotail = NULL;
- lo->lo_bio = bio->bi_next;
- bio->bi_next = NULL;
- }
- spin_unlock_irq(&lo->lo_lock);
+ /*
+ * initialize one page "buffer-bio"
+ */
+ bio->bi_sector = merge->bi_sector;
+ bio->bi_next = NULL;
+ bio->bi_bdev = lo->lo_device;
+ bio->bi_flags = 0;
+ bio->bi_rw = orig_bio->bi_rw;
+ bio->bi_vcnt = 1;
+ bio->bi_idx = 0;
+ bio->bi_phys_segments = 0;
+ bio->bi_hw_segments = 0;
+ bio->bi_size = len = orig_bio->bi_io_vec[merge->bi_idx].bv_len;
+ /* bio->bi_max not touched */
+ bio->bi_io_vec[0].bv_len = len;
+ bio->bi_io_vec[0].bv_offset = 0;
+ bio->bi_end_io = loop_end_io_transfer;
+ /* bio->bi_cnt not touched */
+ /* bio->bi_private not touched */
+ /* bio->bi_destructor not touched */
- return bio;
-}
+ /*
+ * initialize "buffer-bio" extension. This extension is
+ * permanently glued to above "buffer-bio" via bio->bi_private
+ */
+ extension = bio->bi_private;
+ extension->bioext_merge = merge;
+ extension->bioext_loop = lo;
+ extension->bioext_sector = merge->bi_sector;
+ extension->bioext_index = merge->bi_idx;
+ extension->bioext_size = len;
-/*
- * if this was a WRITE lo->transfer stuff has already been done. for READs,
- * queue it for the loop thread and let it do the transfer out of
- * bi_end_io context (we don't want to do decrypt of a page with irqs
- * disabled)
- */
-static void loop_end_io_transfer(struct bio *bio)
-{
- struct bio *rbh = bio->bi_private;
- struct loop_device *lo = &loop_dev[minor(to_kdev_t(rbh->bi_bdev->bd_dev))];
- int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
+ /*
+ * prepare "merge-bio" for next vec
+ */
+ merge->bi_sector += len >> 9;
+ merge->bi_idx++;
- if (!uptodate || bio_rw(bio) == WRITE) {
- bio_endio(rbh, uptodate);
- if (atomic_dec_and_test(&lo->lo_pending))
- up(&lo->lo_bh_mutex);
- loop_put_buffer(bio);
- } else
- loop_add_bio(lo, bio);
+ return bio;
}
-static struct bio *loop_get_buffer(struct loop_device *lo, struct bio *rbh)
+static int figure_loop_size(struct loop_device *lo)
{
- struct bio *bio;
+ loff_t size = lo->lo_backing_file->f_dentry->d_inode->i_mapping->host->i_size;
+ sector_t x;
/*
- * for xfer_funcs that can operate on the same bh, do that
+ * Unfortunately, if we want to do I/O on the device,
+ * the number of 512-byte sectors has to fit into a sector_t.
*/
- if (lo->lo_flags & LO_FLAGS_BH_REMAP) {
- bio = rbh;
- goto out_bh;
- }
+ size = (size - lo->lo_offset) >> 9;
+ x = (sector_t)size;
+ if ((loff_t)x != size)
+ return -EFBIG;
+ /*
+ * Convert sectors to blocks
+ */
+ size >>= (BLOCK_SIZE_BITS - 9);
- bio = bio_copy(rbh, GFP_NOIO, rbh->bi_rw & WRITE);
+ loop_sizes[lo->lo_number] = (sector_t)size;
+ return 0;
+}
- bio->bi_end_io = loop_end_io_transfer;
- bio->bi_private = rbh;
+static inline int lo_do_transfer(struct loop_device *lo, int cmd, char *rbuf,
+ char *lbuf, int size, int rblock)
+{
+ if (!lo->transfer)
+ return 0;
-out_bh:
- bio->bi_sector = rbh->bi_sector + (lo->lo_offset >> 9);
- bio->bi_rw = rbh->bi_rw;
- bio->bi_bdev = lo->lo_device;
+ return lo->transfer(lo, cmd, rbuf, lbuf, size, rblock);
+}
- return bio;
+static int loop_file_io(struct file *file, char *buf, int size, loff_t *ppos, int w)
+{
+ mm_segment_t fs;
+ int x, y, z;
+
+ y = 0;
+ do {
+ z = size - y;
+ fs = get_fs();
+ set_fs(get_ds());
+ if (w) {
+ x = file->f_op->write(file, buf + y, z, ppos);
+ set_fs(fs);
+ } else {
+ x = file->f_op->read(file, buf + y, z, ppos);
+ set_fs(fs);
+ if (!x)
+ return 1;
+ }
+ if (x < 0) {
+ if ((x == -EAGAIN) || (x == -ENOMEM) || (x == -ERESTART) || (x == -EINTR)) {
+ blk_run_queues();
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(HZ / 2);
+ continue;
+ }
+ return 1;
+ }
+ y += x;
+ } while (y < size);
+ return 0;
}
-static int
-bio_transfer(struct loop_device *lo, struct bio *to_bio,
- struct bio *from_bio)
-{
- unsigned long IV = loop_get_iv(lo, from_bio->bi_sector);
- struct bio_vec *from_bvec, *to_bvec;
- char *vto, *vfrom;
- int ret = 0, i;
-
- __bio_for_each_segment(from_bvec, from_bio, i, 0) {
- to_bvec = &to_bio->bi_io_vec[i];
-
- kmap(from_bvec->bv_page);
- kmap(to_bvec->bv_page);
- vfrom = page_address(from_bvec->bv_page) + from_bvec->bv_offset;
- vto = page_address(to_bvec->bv_page) + to_bvec->bv_offset;
- ret |= lo_do_transfer(lo, bio_data_dir(to_bio), vto, vfrom,
- from_bvec->bv_len, IV);
- kunmap(from_bvec->bv_page);
- kunmap(to_bvec->bv_page);
- }
+static int do_bio_filebacked(struct loop_device *lo, struct bio *bio)
+{
+ loff_t pos;
+ struct file *file = lo->lo_backing_file;
+ char *data, *buf;
+ unsigned int size, len;
+ sector_t IV;
- return ret;
+ pos = ((loff_t) bio->bi_sector << 9) + lo->lo_offset;
+ buf = page_address(lo->lo_bio_free0->bi_io_vec[0].bv_page);
+ IV = bio->bi_sector + (lo->lo_offset >> 9);
+ do {
+ len = bio->bi_io_vec[bio->bi_idx].bv_len;
+ data = bio_data(bio);
+ while (len > 0) {
+ size = PAGE_SIZE;
+ if (size > len)
+ size = len;
+ if (bio_rw(bio) == WRITE) {
+ if (lo_do_transfer(lo, WRITE, buf, data, size, IV)) {
+ printk(KERN_ERR "loop: write transfer error, sector %llu\n", (unsigned long long)IV);
+ return 1;
+ }
+ if (loop_file_io(file, buf, size, &pos, 1)) {
+ printk(KERN_ERR "loop: write i/o error, sector %llu\n", (unsigned long long)IV);
+ return 1;
+ }
+ } else {
+ if (loop_file_io(file, buf, size, &pos, 0)) {
+ printk(KERN_ERR "loop: read i/o error, sector %llu\n", (unsigned long long)IV);
+ return 1;
+ }
+ if (lo_do_transfer(lo, READ, buf, data, size, IV)) {
+ printk(KERN_ERR "loop: read transfer error, sector %llu\n", (unsigned long long)IV);
+ return 1;
+ }
+ }
+ data += size;
+ len -= size;
+ IV += size >> 9;
+ }
+ } while (++bio->bi_idx < bio->bi_vcnt);
+ return 0;
}
-
+
static int loop_make_request(request_queue_t *q, struct bio *old_bio)
{
- struct bio *new_bio = NULL;
+ struct bio *new_bio, *merge;
struct loop_device *lo;
- unsigned long IV;
- int rw = bio_rw(old_bio);
+ struct loop_bio_extension *extension;
+ int rw = bio_rw(old_bio), y;
int unit = minor(to_kdev_t(old_bio->bi_bdev->bd_dev));
if (unit >= max_loop)
@@ -528,27 +620,57 @@
* file backed, queue for loop_thread to handle
*/
if (lo->lo_flags & LO_FLAGS_DO_BMAP) {
- loop_add_bio(lo, old_bio);
+ loop_add_queue_last(lo, old_bio, &lo->lo_bio_que0);
+ return 0;
+ }
+
+ /*
+ * device backed, just remap bdev & sector for NONE transfer
+ */
+ if (lo->lo_encrypt_type == LO_CRYPT_NONE) {
+ old_bio->bi_sector += lo->lo_offset >> 9;
+ old_bio->bi_bdev = lo->lo_device;
+ generic_make_request(old_bio);
+ if (atomic_dec_and_test(&lo->lo_pending))
+ wake_up_interruptible(&lo->lo_bio_wait);
return 0;
}
/*
- * piggy old buffer on original, and submit for I/O
+ * device backed, start reads and writes now if buffer available
*/
- new_bio = loop_get_buffer(lo, old_bio);
- IV = loop_get_iv(lo, old_bio->bi_sector);
+ merge = NULL;
+ try_next_old_bio_vec:
+ new_bio = loop_get_buffer(lo, old_bio, 0, &merge);
+ if (!new_bio) {
+ /* just queue request and let thread handle allocs later */
+ if (merge)
+ loop_add_queue_last(lo, merge, &lo->lo_bio_que1);
+ else
+ loop_add_queue_last(lo, old_bio, &lo->lo_bio_que2);
+ return 0;
+ }
if (rw == WRITE) {
- if (bio_transfer(lo, new_bio, old_bio))
- goto err;
+ extension = new_bio->bi_private;
+ y = extension->bioext_index;
+ if (lo_do_transfer(lo, WRITE, page_address(new_bio->bi_io_vec[0].bv_page), page_address(old_bio->bi_io_vec[y].bv_page) + old_bio->bi_io_vec[y].bv_offset, extension->bioext_size, extension->bioext_sector)) {
+ clear_bit(BIO_UPTODATE, &merge->bi_flags);
+ }
}
+ /* merge & old_bio may vanish during generic_make_request() */
+ /* if last vec gets processed before function returns */
+ y = (merge->bi_idx < old_bio->bi_vcnt) ? 1 : 0;
generic_make_request(new_bio);
+
+ /* other vecs may need processing too */
+ if (y)
+ goto try_next_old_bio_vec;
return 0;
err:
if (atomic_dec_and_test(&lo->lo_pending))
- up(&lo->lo_bh_mutex);
- loop_put_buffer(new_bio);
+ wake_up_interruptible(&lo->lo_bio_wait);
out:
bio_io_error(old_bio);
return 0;
@@ -557,26 +679,6 @@
goto out;
}
-static inline void loop_handle_bio(struct loop_device *lo, struct bio *bio)
-{
- int ret;
-
- /*
- * For block backed loop, we know this is a READ
- */
- if (lo->lo_flags & LO_FLAGS_DO_BMAP) {
- ret = do_bio_filebacked(lo, bio);
- bio_endio(bio, !ret);
- } else {
- struct bio *rbh = bio->bi_private;
-
- ret = bio_transfer(lo, bio, rbh);
-
- bio_endio(rbh, !ret);
- loop_put_buffer(bio);
- }
-}
-
/*
* worker thread that handles reads/writes to file backed loop devices,
* to avoid blocking in our make_request_fn. it also does loop decrypting
@@ -586,9 +688,15 @@
static int loop_thread(void *data)
{
struct loop_device *lo = data;
- struct bio *bio;
+ struct bio *bio, *xbio, *merge;
+ struct loop_bio_extension *extension;
+ int x, y, flushcnt = 0;
+ wait_queue_t waitq;
+ init_waitqueue_entry(&waitq, current);
daemonize();
+ exit_files(current);
+ reparent_to_init();
sprintf(current->comm, "loop%d", lo->lo_number);
current->flags |= PF_IOTHREAD; /* loop can be used in an encrypted device
@@ -611,23 +719,132 @@
up(&lo->lo_sem);
for (;;) {
- down_interruptible(&lo->lo_bh_mutex);
+ add_wait_queue(&lo->lo_bio_wait, &waitq);
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!atomic_read(&lo->lo_pending))
+ break;
+
+ x = 0;
+ spin_lock_irq(&lo->lo_lock);
+ if (lo->lo_bio_que0) {
+ /* don't sleep if device backed READ needs processing */
+ /* don't sleep if file backed READ/WRITE needs processing */
+ x = 1;
+ } else if (lo->lo_bio_que1) {
+ /* don't sleep if a buffer-bio is available */
+ /* don't sleep if need-buffer-bio request is not set */
+ if (lo->lo_bio_free0 || !(lo->lo_bio_need & 1))
+ x = 1;
+ } else if (lo->lo_bio_que2) {
+ /* don't sleep if a merge-bio is available */
+ /* don't sleep if need-merge-bio request is not set */
+ if (lo->lo_bio_free1 || !(lo->lo_bio_need & 2))
+ x = 1;
+ }
+ spin_unlock_irq(&lo->lo_lock);
+ if (x)
+ break;
+
+ schedule();
+ }
+ current->state = TASK_RUNNING;
+ remove_wait_queue(&lo->lo_bio_wait, &waitq);
+
/*
- * could be upped because of tear-down, not because of
+ * could be woken because of tear-down, not because of
* pending work
*/
if (!atomic_read(&lo->lo_pending))
break;
- bio = loop_get_bio(lo);
- if (!bio) {
- printk("loop: missing bio\n");
+ bio = loop_get_bio(lo, &x);
+ if (!bio)
continue;
+
+ /*
+ * x list tag usage(has-buffer,has-merge)
+ * --- -------- --------------------------
+ * 0 lo->lo_bio_que0 dev-r(y,y) / file-rw
+ * 1 lo->lo_bio_que1 dev-rw(n,y)
+ * 2 lo->lo_bio_que2 dev-rw(n,n)
+ */
+ if (x >= 1) {
+ /* loop_make_request didn't allocate a buffer, do that now */
+ if (x == 1) {
+ merge = bio;
+ bio = merge->bi_private;
+ } else {
+ merge = NULL;
+ }
+ try_next_bio_vec:
+ xbio = loop_get_buffer(lo, bio, 1, &merge);
+ if (!xbio) {
+ blk_run_queues();
+ flushcnt = 0;
+ if (merge)
+ loop_add_queue_first(lo, merge, &lo->lo_bio_que1);
+ else
+ loop_add_queue_first(lo, bio, &lo->lo_bio_que2);
+ /* lo->lo_bio_need should be non-zero now, go back to sleep */
+ continue;
+ }
+ if (bio_rw(bio) == WRITE) {
+ extension = xbio->bi_private;
+ y = extension->bioext_index;
+ if (lo_do_transfer(lo, WRITE, page_address(xbio->bi_io_vec[0].bv_page), page_address(bio->bi_io_vec[y].bv_page) + bio->bi_io_vec[y].bv_offset, extension->bioext_size, extension->bioext_sector)) {
+ clear_bit(BIO_UPTODATE, &merge->bi_flags);
+ }
+ }
+
+ /* merge & bio may vanish during generic_make_request() */
+ /* if last vec gets processed before function returns */
+ y = (merge->bi_idx < bio->bi_vcnt) ? 1 : 0;
+ generic_make_request(xbio);
+
+ /* start I/O if there are no more requests lacking buffers */
+ x = 0;
+ spin_lock_irq(&lo->lo_lock);
+ if (!y && !lo->lo_bio_que1 && !lo->lo_bio_que2)
+ x = 1;
+ spin_unlock_irq(&lo->lo_lock);
+ if (x || (++flushcnt >= lo->lo_bio_flsh)) {
+ blk_run_queues();
+ flushcnt = 0;
+ }
+
+ /* other vecs may need processing too */
+ if (y)
+ goto try_next_bio_vec;
+
+ /* request not completely processed yet */
+ continue;
+ }
+
+ if (lo->lo_flags & LO_FLAGS_DO_BMAP) {
+ /* request is for file backed device */
+ y = do_bio_filebacked(lo, bio);
+ bio->bi_next = NULL;
+ bio_endio(bio, !y);
+ } else {
+ /* device backed read has completed, do decrypt now */
+ extension = bio->bi_private;
+ merge = extension->bioext_merge;
+ y = extension->bioext_index;
+ xbio = merge->bi_private;
+ if (lo_do_transfer(lo, READ, page_address(bio->bi_io_vec[0].bv_page), page_address(xbio->bi_io_vec[y].bv_page) + xbio->bi_io_vec[y].bv_offset, extension->bioext_size, extension->bioext_sector)) {
+ clear_bit(BIO_UPTODATE, &merge->bi_flags);
+ }
+ loop_put_buffer(lo, bio, 0);
+ if (!atomic_dec_and_test(&merge->bi_cnt))
+ continue;
+ xbio->bi_next = NULL;
+ bio_endio(xbio, test_bit(BIO_UPTODATE, &merge->bi_flags));
+ loop_put_buffer(lo, merge, 1);
}
- loop_handle_bio(lo, bio);
/*
- * upped both for pending work and tear-down, lo_pending
+ * woken both for pending work and tear-down, lo_pending
* will hit zero then
*/
if (atomic_dec_and_test(&lo->lo_pending))
@@ -647,6 +864,7 @@
struct block_device *lo_device;
int lo_flags = 0;
int error;
+ int bs;
MOD_INC_USE_COUNT;
@@ -665,33 +883,43 @@
if (!(file->f_mode & FMODE_WRITE))
lo_flags |= LO_FLAGS_READ_ONLY;
+ lo->lo_bio_free1 = lo->lo_bio_free0 = lo->lo_bio_que2 = lo->lo_bio_que1 = lo->lo_bio_que0 = NULL;
+ lo->lo_bio_need = lo->lo_bio_flsh = 0;
+ init_waitqueue_head(&lo->lo_bio_wait);
if (S_ISBLK(inode->i_mode)) {
lo_device = inode->i_bdev;
if (lo_device == bdev) {
error = -EBUSY;
- goto out;
+ goto out_putf;
+ }
+ if (loop_prealloc_init(lo, 0)) {
+ error = -ENOMEM;
+ goto out_putf;
}
} else if (S_ISREG(inode->i_mode)) {
- struct address_space_operations *aops = inode->i_mapping->a_ops;
/*
* If we can't read - sorry. If we only can't write - well,
* it's going to be read-only.
*/
- if (!aops->readpage)
+ if (!file->f_op || !file->f_op->read)
goto out_putf;
- if (!aops->prepare_write || !aops->commit_write)
+ if (!file->f_op->write)
lo_flags |= LO_FLAGS_READ_ONLY;
lo_device = inode->i_sb->s_bdev;
lo_flags |= LO_FLAGS_DO_BMAP;
+ if (loop_prealloc_init(lo, 1)) {
+ error = -ENOMEM;
+ goto out_putf;
+ }
error = 0;
} else
goto out_putf;
get_file(file);
- if (IS_RDONLY (inode) || bdev_read_only(lo_device)
+ if ((S_ISREG(inode->i_mode) && IS_RDONLY(inode)) || bdev_read_only(lo_device)
|| !(lo_file->f_mode & FMODE_WRITE))
lo_flags |= LO_FLAGS_READ_ONLY;
@@ -702,13 +930,28 @@
lo->lo_backing_file = file;
lo->transfer = NULL;
lo->ioctl = NULL;
- figure_loop_size(lo);
+ if (figure_loop_size(lo)) {
+ loop_prealloc_cleanup(lo);
+ error = -EFBIG;
+ fput(file);
+ goto out_putf;
+ }
lo->old_gfp_mask = inode->i_mapping->gfp_mask;
inode->i_mapping->gfp_mask = GFP_NOIO;
- set_blocksize(bdev, block_size(lo_device));
+ bs = block_size(lo_device);
+ if (S_ISREG(inode->i_mode)) {
+ int x = (int) loop_sizes[lo->lo_number];
+
+ if ((bs == 8192) && (x & 7))
+ bs = 4096;
+ if ((bs == 4096) && (x & 3))
+ bs = 2048;
+ if ((bs == 2048) && (x & 1))
+ bs = 1024;
+ }
+ set_blocksize(bdev, bs);
- lo->lo_bio = lo->lo_biotail = NULL;
kernel_thread(loop_thread, lo, CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
down(&lo->lo_sem);
@@ -767,11 +1010,12 @@
spin_lock_irq(&lo->lo_lock);
lo->lo_state = Lo_rundown;
if (atomic_dec_and_test(&lo->lo_pending))
- up(&lo->lo_bh_mutex);
+ wake_up_interruptible(&lo->lo_bio_wait);
spin_unlock_irq(&lo->lo_lock);
down(&lo->lo_sem);
+ loop_prealloc_cleanup(lo);
lo->lo_backing_file = NULL;
loop_release_xfer(lo);
@@ -798,6 +1042,7 @@
struct loop_info info;
int err;
unsigned int type;
+ loff_t offset;
if (lo->lo_encrypt_key_size && lo->lo_key_owner != current->uid &&
!capable(CAP_SYS_ADMIN))
@@ -813,13 +1058,23 @@
return -EINVAL;
if (type == LO_CRYPT_XOR && info.lo_encrypt_key_size == 0)
return -EINVAL;
+
err = loop_release_xfer(lo);
if (!err)
err = loop_init_xfer(lo, type, &info);
+
+ offset = lo->lo_offset;
+ if (offset != info.lo_offset) {
+ lo->lo_offset = info.lo_offset;
+ if (figure_loop_size(lo)){
+ err = -EFBIG;
+ lo->lo_offset = offset;
+ }
+ }
+
if (err)
return err;
- lo->lo_offset = info.lo_offset;
strncpy(lo->lo_name, info.lo_name, LO_NAME_SIZE);
lo->transfer = xfer_funcs[type]->transfer;
@@ -832,7 +1087,7 @@
info.lo_encrypt_key_size);
lo->lo_key_owner = current->uid;
}
- figure_loop_size(lo);
+
return 0;
}
@@ -926,7 +1181,7 @@
static int lo_open(struct inode *inode, struct file *file)
{
struct loop_device *lo;
- int dev, type;
+ int dev;
if (!inode)
return -EINVAL;
@@ -941,10 +1196,6 @@
lo = &loop_dev[dev];
MOD_INC_USE_COUNT;
down(&lo->lo_ctl_mutex);
-
- type = lo->lo_encrypt_type;
- if (type && xfer_funcs[type] && xfer_funcs[type]->lock)
- xfer_funcs[type]->lock(lo);
lo->lo_refcnt++;
up(&lo->lo_ctl_mutex);
return 0;
@@ -953,7 +1204,7 @@
static int lo_release(struct inode *inode, struct file *file)
{
struct loop_device *lo;
- int dev, type;
+ int dev;
if (!inode)
return 0;
@@ -968,11 +1219,7 @@
lo = &loop_dev[dev];
down(&lo->lo_ctl_mutex);
- type = lo->lo_encrypt_type;
--lo->lo_refcnt;
- if (xfer_funcs[type] && xfer_funcs[type]->unlock)
- xfer_funcs[type]->unlock(lo);
-
up(&lo->lo_ctl_mutex);
MOD_DEC_USE_COUNT;
return 0;
@@ -1047,7 +1294,7 @@
if (!loop_dev)
return -ENOMEM;
- loop_sizes = kmalloc(max_loop * sizeof(int), GFP_KERNEL);
+ loop_sizes = kmalloc(max_loop * sizeof(loop_sizes[0]), GFP_KERNEL);
if (!loop_sizes)
goto out_mem;
@@ -1059,16 +1306,23 @@
memset(lo, 0, sizeof(struct loop_device));
init_MUTEX(&lo->lo_ctl_mutex);
init_MUTEX_LOCKED(&lo->lo_sem);
- init_MUTEX_LOCKED(&lo->lo_bh_mutex);
lo->lo_number = i;
spin_lock_init(&lo->lo_lock);
}
- memset(loop_sizes, 0, max_loop * sizeof(int));
+ memset(loop_sizes, 0, max_loop * sizeof(*loop_sizes));
blk_size[MAJOR_NR] = loop_sizes;
for (i = 0; i < max_loop; i++)
register_disk(NULL, mk_kdev(MAJOR_NR, i), 1, &lo_fops, 0);
+ for (i = 0; i < (sizeof(lo_prealloc) / sizeof(int)); i += 2) {
+ if (!lo_prealloc[i])
+ continue;
+ if (lo_prealloc[i] < LO_PREALLOC_MIN)
+ lo_prealloc[i] = LO_PREALLOC_MIN;
+ if (lo_prealloc[i] > LO_PREALLOC_MAX)
+ lo_prealloc[i] = LO_PREALLOC_MAX;
+ }
printk(KERN_INFO "loop: loaded (max %d devices)\n", max_loop);
return 0;
diff -urN linux-2.5.25/fs/block_dev.c linux-2.5.25-loopfix/fs/block_dev.c
--- linux-2.5.25/fs/block_dev.c Sat Jul 6 19:55:59 2002
+++ linux-2.5.25-loopfix/fs/block_dev.c Wed Jul 10 23:51:20 2002
@@ -539,10 +539,10 @@
bdev->bd_op = get_blkfops(major(dev));
if (!bdev->bd_op)
goto out;
- owner = bdev->bd_op->owner;
- if (owner)
- __MOD_INC_USE_COUNT(owner);
}
+ owner = bdev->bd_op->owner;
+ if (owner)
+ __MOD_INC_USE_COUNT(owner);
if (!bdev->bd_contains) {
unsigned minor = minor(dev);
struct gendisk *g = get_gendisk(dev);
diff -urN linux-2.5.25/include/linux/loop.h linux-2.5.25-loopfix/include/linux/loop.h
--- linux-2.5.25/include/linux/loop.h Wed Jun 19 12:14:15 2002
+++ linux-2.5.25-loopfix/include/linux/loop.h Wed Jul 10 21:53:19 2002
@@ -17,6 +17,11 @@
#ifdef __KERNEL__
+/* definitions for IV metric -- cryptoapi specific */
+#define LOOP_IV_SECTOR_BITS 9
+#define LOOP_IV_SECTOR_SIZE (1 << LOOP_IV_SECTOR_BITS)
+typedef /*FIXME sector_t*/int loop_iv_t;
+
/* Possible states of device */
enum {
Lo_unbound,
@@ -33,7 +38,7 @@
int lo_flags;
int (*transfer)(struct loop_device *, int cmd,
char *raw_buf, char *loop_buf, int size,
- int real_block);
+ /*FIXME sector_t*/int real_block);
char lo_name[LO_NAME_SIZE];
char lo_encrypt_key[LO_KEY_SIZE];
__u32 lo_init[2];
@@ -49,13 +54,18 @@
int old_gfp_mask;
spinlock_t lo_lock;
- struct bio *lo_bio;
- struct bio *lo_biotail;
+ struct bio *lo_bio_que0;
+ struct bio *lo_bio_que1;
int lo_state;
struct semaphore lo_sem;
struct semaphore lo_ctl_mutex;
- struct semaphore lo_bh_mutex;
atomic_t lo_pending;
+ struct bio *lo_bio_que2;
+ struct bio *lo_bio_free0;
+ struct bio *lo_bio_free1;
+ int lo_bio_flsh;
+ int lo_bio_need;
+ wait_queue_head_t lo_bio_wait;
};
typedef int (* transfer_proc_t)(struct loop_device *, int cmd,
@@ -69,7 +79,6 @@
*/
#define LO_FLAGS_DO_BMAP 1
#define LO_FLAGS_READ_ONLY 2
-#define LO_FLAGS_BH_REMAP 4
/*
* Note that this structure gets the wrong offsets when directly used
@@ -114,6 +123,8 @@
#define LO_CRYPT_IDEA 6
#define LO_CRYPT_DUMMY 9
#define LO_CRYPT_SKIPJACK 10
+#define LO_CRYPT_AES 16
+#define LO_CRYPT_CRYPTOAPI 18
#define MAX_LO_CRYPT 20
#ifdef __KERNEL__
diff -urN linux-2.5.25/kernel/ksyms.c linux-2.5.25-loopfix/kernel/ksyms.c
--- linux-2.5.25/kernel/ksyms.c Sat Jul 6 19:56:00 2002
+++ linux-2.5.25-loopfix/kernel/ksyms.c Wed Jul 10 21:21:19 2002
@@ -88,6 +88,7 @@
EXPORT_SYMBOL(do_munmap);
EXPORT_SYMBOL(do_brk);
EXPORT_SYMBOL(exit_mm);
+EXPORT_SYMBOL(exit_files);
/* internal kernel memory management */
EXPORT_SYMBOL(_alloc_pages);
-
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This archive was generated by hypermail 2b29 : Tue Jul 23 2002 - 22:00:20 EST