#include <linux/config.h>
#include <linux/kernel.h>
-#include <linux/syscalls.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/percpu.h>
#include <linux/bio.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
-#include <linux/bitops.h>
+#include <asm/bitops.h>
static int fsync_buffers_list(spinlock_t *lock, struct list_head *list);
static void invalidate_bh_lrus(void);
#define BH_ENTRY(list) list_entry((list), struct buffer_head, b_assoc_buffers)
+struct bh_wait_queue {
+ struct buffer_head *bh;
+ wait_queue_t wait;
+};
+
+#define __DEFINE_BH_WAIT(name, b, f) \
+ struct bh_wait_queue name = { \
+ .bh = b, \
+ .wait = { \
+ .task = current, \
+ .flags = f, \
+ .func = bh_wake_function, \
+ .task_list = \
+ LIST_HEAD_INIT(name.wait.task_list),\
+ }, \
+ }
+#define DEFINE_BH_WAIT(name, bh) __DEFINE_BH_WAIT(name, bh, 0)
+#define DEFINE_BH_WAIT_EXCLUSIVE(name, bh) \
+ __DEFINE_BH_WAIT(name, bh, WQ_FLAG_EXCLUSIVE)
+
+/*
+ * Hashed waitqueue_head's for wait_on_buffer()
+ */
+#define BH_WAIT_TABLE_ORDER 7
+static struct bh_wait_queue_head {
+ wait_queue_head_t wqh;
+} ____cacheline_aligned_in_smp bh_wait_queue_heads[1<<BH_WAIT_TABLE_ORDER];
+
inline void
init_buffer(struct buffer_head *bh, bh_end_io_t *handler, void *private)
{
bh->b_private = private;
}
-static int sync_buffer(void *word)
+/*
+ * Return the address of the waitqueue_head to be used for this
+ * buffer_head
+ */
+wait_queue_head_t *bh_waitq_head(struct buffer_head *bh)
+{
+ return &bh_wait_queue_heads[hash_ptr(bh, BH_WAIT_TABLE_ORDER)].wqh;
+}
+EXPORT_SYMBOL(bh_waitq_head);
+
+void wake_up_buffer(struct buffer_head *bh)
+{
+ wait_queue_head_t *wq = bh_waitq_head(bh);
+
+ smp_mb();
+ if (waitqueue_active(wq))
+ __wake_up(wq, TASK_INTERRUPTIBLE|TASK_UNINTERRUPTIBLE, 1, bh);
+}
+EXPORT_SYMBOL(wake_up_buffer);
+
+static int bh_wake_function(wait_queue_t *wait, unsigned mode,
+ int sync, void *key)
+{
+ struct buffer_head *bh = key;
+ struct bh_wait_queue *wq;
+
+ wq = container_of(wait, struct bh_wait_queue, wait);
+ if (wq->bh != bh || buffer_locked(bh))
+ return 0;
+ else
+ return autoremove_wake_function(wait, mode, sync, key);
+}
+
+static void sync_buffer(struct buffer_head *bh)
{
struct block_device *bd;
- struct buffer_head *bh
- = container_of(word, struct buffer_head, b_state);
smp_mb();
bd = bh->b_bdev;
if (bd)
blk_run_address_space(bd->bd_inode->i_mapping);
- io_schedule();
- return 0;
}
void fastcall __lock_buffer(struct buffer_head *bh)
{
- wait_on_bit_lock(&bh->b_state, BH_Lock, sync_buffer,
- TASK_UNINTERRUPTIBLE);
+ wait_queue_head_t *wqh = bh_waitq_head(bh);
+ DEFINE_BH_WAIT_EXCLUSIVE(wait, bh);
+
+ do {
+ prepare_to_wait_exclusive(wqh, &wait.wait,
+ TASK_UNINTERRUPTIBLE);
+ if (buffer_locked(bh)) {
+ sync_buffer(bh);
+ io_schedule();
+ }
+ } while (test_set_buffer_locked(bh));
+ finish_wait(wqh, &wait.wait);
}
EXPORT_SYMBOL(__lock_buffer);
{
clear_buffer_locked(bh);
smp_mb__after_clear_bit();
- wake_up_bit(&bh->b_state, BH_Lock);
+ wake_up_buffer(bh);
}
/*
*/
void __wait_on_buffer(struct buffer_head * bh)
{
- wait_on_bit(&bh->b_state, BH_Lock, sync_buffer, TASK_UNINTERRUPTIBLE);
+ wait_queue_head_t *wqh = bh_waitq_head(bh);
+ DEFINE_BH_WAIT(wait, bh);
+
+ do {
+ prepare_to_wait(wqh, &wait.wait, TASK_UNINTERRUPTIBLE);
+ if (buffer_locked(bh)) {
+ sync_buffer(bh);
+ io_schedule();
+ }
+ } while (buffer_locked(bh));
+ finish_wait(wqh, &wait.wait);
+}
+
+static void
+__set_page_buffers(struct page *page, struct buffer_head *head)
+{
+ page_cache_get(page);
+ SetPagePrivate(page);
+ page->private = (unsigned long)head;
}
static void
* The retry flag is used to differentiate async IO (paging, swapping)
* which may not fail from ordinary buffer allocations.
*/
-struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
- int retry)
+static struct buffer_head *
+create_buffers(struct page * page, unsigned long size, int retry)
{
struct buffer_head *bh, *head;
long offset;
free_more_memory();
goto try_again;
}
-EXPORT_SYMBOL_GPL(alloc_page_buffers);
static inline void
link_dev_buffers(struct page *page, struct buffer_head *head)
bh = bh->b_this_page;
} while (bh);
tail->b_this_page = head;
- attach_page_buffers(page, head);
+ __set_page_buffers(page, head);
}
/*
/*
* Allocate some buffers for this page
*/
- bh = alloc_page_buffers(page, size, 0);
+ bh = create_buffers(page, size, 0);
if (!bh)
goto failed;
{
struct buffer_head *bh, *head, *tail;
- head = alloc_page_buffers(page, blocksize, 1);
+ head = create_buffers(page, blocksize, 1);
bh = head;
do {
bh->b_state |= b_state;
bh = bh->b_this_page;
} while (bh != head);
}
- attach_page_buffers(page, head);
+ __set_page_buffers(page, head);
spin_unlock(&page->mapping->private_lock);
}
EXPORT_SYMBOL(create_empty_buffers);
int err;
err = -EFBIG;
- limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+ limit = current->rlim[RLIMIT_FSIZE].rlim_cur;
if (limit != RLIM_INFINITY && size > (loff_t)limit) {
send_sig(SIGXFSZ, current, 0);
goto out;
memset(kaddr+zerofrom, 0, PAGE_CACHE_SIZE-zerofrom);
flush_dcache_page(new_page);
kunmap_atomic(kaddr, KM_USER0);
- generic_commit_write(NULL, new_page, zerofrom, PAGE_CACHE_SIZE);
+ __block_commit_write(inode, new_page,
+ zerofrom, PAGE_CACHE_SIZE);
unlock_page(new_page);
page_cache_release(new_page);
}
void __init buffer_init(void)
{
+ int i;
int nrpages;
bh_cachep = kmem_cache_create("buffer_head",
sizeof(struct buffer_head), 0,
SLAB_PANIC, init_buffer_head, NULL);
+ for (i = 0; i < ARRAY_SIZE(bh_wait_queue_heads); i++)
+ init_waitqueue_head(&bh_wait_queue_heads[i].wqh);
/*
* Limit the bh occupancy to 10% of ZONE_NORMAL
git://git.onelab.eu / linux-2.6.git / blobdiff