Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
new file mode 100644
index 0000000..4c0a3ac
--- /dev/null
+++ b/fs/jfs/jfs_metapage.c
@@ -0,0 +1,580 @@
+/*
+ * Copyright (C) International Business Machines Corp., 2000-2003
+ * Portions Copyright (C) Christoph Hellwig, 2001-2002
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/buffer_head.h>
+#include <linux/mempool.h>
+#include <linux/delay.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_txnmgr.h"
+#include "jfs_debug.h"
+
+static DEFINE_SPINLOCK(meta_lock);
+
+#ifdef CONFIG_JFS_STATISTICS
+static struct {
+ uint pagealloc; /* # of page allocations */
+ uint pagefree; /* # of page frees */
+ uint lockwait; /* # of sleeping lock_metapage() calls */
+} mpStat;
+#endif
+
+
+#define HASH_BITS 10 /* This makes hash_table 1 4K page */
+#define HASH_SIZE (1 << HASH_BITS)
+static struct metapage **hash_table = NULL;
+static unsigned long hash_order;
+
+
+static inline int metapage_locked(struct metapage *mp)
+{
+ return test_bit(META_locked, &mp->flag);
+}
+
+static inline int trylock_metapage(struct metapage *mp)
+{
+ return test_and_set_bit(META_locked, &mp->flag);
+}
+
+static inline void unlock_metapage(struct metapage *mp)
+{
+ clear_bit(META_locked, &mp->flag);
+ wake_up(&mp->wait);
+}
+
+static void __lock_metapage(struct metapage *mp)
+{
+ DECLARE_WAITQUEUE(wait, current);
+
+ INCREMENT(mpStat.lockwait);
+
+ add_wait_queue_exclusive(&mp->wait, &wait);
+ do {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (metapage_locked(mp)) {
+ spin_unlock(&meta_lock);
+ schedule();
+ spin_lock(&meta_lock);
+ }
+ } while (trylock_metapage(mp));
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&mp->wait, &wait);
+}
+
+/* needs meta_lock */
+static inline void lock_metapage(struct metapage *mp)
+{
+ if (trylock_metapage(mp))
+ __lock_metapage(mp);
+}
+
+#define METAPOOL_MIN_PAGES 32
+static kmem_cache_t *metapage_cache;
+static mempool_t *metapage_mempool;
+
+static void init_once(void *foo, kmem_cache_t *cachep, unsigned long flags)
+{
+ struct metapage *mp = (struct metapage *)foo;
+
+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR) {
+ mp->lid = 0;
+ mp->lsn = 0;
+ mp->flag = 0;
+ mp->data = NULL;
+ mp->clsn = 0;
+ mp->log = NULL;
+ set_bit(META_free, &mp->flag);
+ init_waitqueue_head(&mp->wait);
+ }
+}
+
+static inline struct metapage *alloc_metapage(int gfp_mask)
+{
+ return mempool_alloc(metapage_mempool, gfp_mask);
+}
+
+static inline void free_metapage(struct metapage *mp)
+{
+ mp->flag = 0;
+ set_bit(META_free, &mp->flag);
+
+ mempool_free(mp, metapage_mempool);
+}
+
+int __init metapage_init(void)
+{
+ /*
+ * Allocate the metapage structures
+ */
+ metapage_cache = kmem_cache_create("jfs_mp", sizeof(struct metapage),
+ 0, 0, init_once, NULL);
+ if (metapage_cache == NULL)
+ return -ENOMEM;
+
+ metapage_mempool = mempool_create(METAPOOL_MIN_PAGES, mempool_alloc_slab,
+ mempool_free_slab, metapage_cache);
+
+ if (metapage_mempool == NULL) {
+ kmem_cache_destroy(metapage_cache);
+ return -ENOMEM;
+ }
+ /*
+ * Now the hash list
+ */
+ for (hash_order = 0;
+ ((PAGE_SIZE << hash_order) / sizeof(void *)) < HASH_SIZE;
+ hash_order++);
+ hash_table =
+ (struct metapage **) __get_free_pages(GFP_KERNEL, hash_order);
+ assert(hash_table);
+ memset(hash_table, 0, PAGE_SIZE << hash_order);
+
+ return 0;
+}
+
+void metapage_exit(void)
+{
+ mempool_destroy(metapage_mempool);
+ kmem_cache_destroy(metapage_cache);
+}
+
+/*
+ * Basically same hash as in pagemap.h, but using our hash table
+ */
+static struct metapage **meta_hash(struct address_space *mapping,
+ unsigned long index)
+{
+#define i (((unsigned long)mapping)/ \
+ (sizeof(struct inode) & ~(sizeof(struct inode) -1 )))
+#define s(x) ((x) + ((x) >> HASH_BITS))
+ return hash_table + (s(i + index) & (HASH_SIZE - 1));
+#undef i
+#undef s
+}
+
+static struct metapage *search_hash(struct metapage ** hash_ptr,
+ struct address_space *mapping,
+ unsigned long index)
+{
+ struct metapage *ptr;
+
+ for (ptr = *hash_ptr; ptr; ptr = ptr->hash_next) {
+ if ((ptr->mapping == mapping) && (ptr->index == index))
+ return ptr;
+ }
+
+ return NULL;
+}
+
+static void add_to_hash(struct metapage * mp, struct metapage ** hash_ptr)
+{
+ if (*hash_ptr)
+ (*hash_ptr)->hash_prev = mp;
+
+ mp->hash_prev = NULL;
+ mp->hash_next = *hash_ptr;
+ *hash_ptr = mp;
+}
+
+static void remove_from_hash(struct metapage * mp, struct metapage ** hash_ptr)
+{
+ if (mp->hash_prev)
+ mp->hash_prev->hash_next = mp->hash_next;
+ else {
+ assert(*hash_ptr == mp);
+ *hash_ptr = mp->hash_next;
+ }
+
+ if (mp->hash_next)
+ mp->hash_next->hash_prev = mp->hash_prev;
+}
+
+struct metapage *__get_metapage(struct inode *inode, unsigned long lblock,
+ unsigned int size, int absolute,
+ unsigned long new)
+{
+ struct metapage **hash_ptr;
+ int l2BlocksPerPage;
+ int l2bsize;
+ struct address_space *mapping;
+ struct metapage *mp;
+ unsigned long page_index;
+ unsigned long page_offset;
+
+ jfs_info("__get_metapage: inode = 0x%p, lblock = 0x%lx", inode, lblock);
+
+ if (absolute)
+ mapping = inode->i_sb->s_bdev->bd_inode->i_mapping;
+ else {
+ /*
+ * If an nfs client tries to read an inode that is larger
+ * than any existing inodes, we may try to read past the
+ * end of the inode map
+ */
+ if ((lblock << inode->i_blkbits) >= inode->i_size)
+ return NULL;
+ mapping = inode->i_mapping;
+ }
+
+ hash_ptr = meta_hash(mapping, lblock);
+again:
+ spin_lock(&meta_lock);
+ mp = search_hash(hash_ptr, mapping, lblock);
+ if (mp) {
+ page_found:
+ if (test_bit(META_stale, &mp->flag)) {
+ spin_unlock(&meta_lock);
+ msleep(1);
+ goto again;
+ }
+ mp->count++;
+ lock_metapage(mp);
+ spin_unlock(&meta_lock);
+ if (test_bit(META_discard, &mp->flag)) {
+ if (!new) {
+ jfs_error(inode->i_sb,
+ "__get_metapage: using a "
+ "discarded metapage");
+ release_metapage(mp);
+ return NULL;
+ }
+ clear_bit(META_discard, &mp->flag);
+ }
+ jfs_info("__get_metapage: found 0x%p, in hash", mp);
+ if (mp->logical_size != size) {
+ jfs_error(inode->i_sb,
+ "__get_metapage: mp->logical_size != size");
+ release_metapage(mp);
+ return NULL;
+ }
+ } else {
+ l2bsize = inode->i_blkbits;
+ l2BlocksPerPage = PAGE_CACHE_SHIFT - l2bsize;
+ page_index = lblock >> l2BlocksPerPage;
+ page_offset = (lblock - (page_index << l2BlocksPerPage)) <<
+ l2bsize;
+ if ((page_offset + size) > PAGE_CACHE_SIZE) {
+ spin_unlock(&meta_lock);
+ jfs_err("MetaData crosses page boundary!!");
+ return NULL;
+ }
+
+ /*
+ * Locks held on aggregate inode pages are usually
+ * not held long, and they are taken in critical code
+ * paths (committing dirty inodes, txCommit thread)
+ *
+ * Attempt to get metapage without blocking, tapping into
+ * reserves if necessary.
+ */
+ mp = NULL;
+ if (JFS_IP(inode)->fileset == AGGREGATE_I) {
+ mp = alloc_metapage(GFP_ATOMIC);
+ if (!mp) {
+ /*
+ * mempool is supposed to protect us from
+ * failing here. We will try a blocking
+ * call, but a deadlock is possible here
+ */
+ printk(KERN_WARNING
+ "__get_metapage: atomic call to mempool_alloc failed.\n");
+ printk(KERN_WARNING
+ "Will attempt blocking call\n");
+ }
+ }
+ if (!mp) {
+ struct metapage *mp2;
+
+ spin_unlock(&meta_lock);
+ mp = alloc_metapage(GFP_NOFS);
+ spin_lock(&meta_lock);
+
+ /* we dropped the meta_lock, we need to search the
+ * hash again.
+ */
+ mp2 = search_hash(hash_ptr, mapping, lblock);
+ if (mp2) {
+ free_metapage(mp);
+ mp = mp2;
+ goto page_found;
+ }
+ }
+ mp->flag = 0;
+ lock_metapage(mp);
+ if (absolute)
+ set_bit(META_absolute, &mp->flag);
+ mp->xflag = COMMIT_PAGE;
+ mp->count = 1;
+ atomic_set(&mp->nohomeok,0);
+ mp->mapping = mapping;
+ mp->index = lblock;
+ mp->page = NULL;
+ mp->logical_size = size;
+ add_to_hash(mp, hash_ptr);
+ spin_unlock(&meta_lock);
+
+ if (new) {
+ jfs_info("__get_metapage: Calling grab_cache_page");
+ mp->page = grab_cache_page(mapping, page_index);
+ if (!mp->page) {
+ jfs_err("grab_cache_page failed!");
+ goto freeit;
+ } else {
+ INCREMENT(mpStat.pagealloc);
+ unlock_page(mp->page);
+ }
+ } else {
+ jfs_info("__get_metapage: Calling read_cache_page");
+ mp->page = read_cache_page(mapping, lblock,
+ (filler_t *)mapping->a_ops->readpage, NULL);
+ if (IS_ERR(mp->page)) {
+ jfs_err("read_cache_page failed!");
+ goto freeit;
+ } else
+ INCREMENT(mpStat.pagealloc);
+ }
+ mp->data = kmap(mp->page) + page_offset;
+ }
+
+ if (new)
+ memset(mp->data, 0, PSIZE);
+
+ jfs_info("__get_metapage: returning = 0x%p", mp);
+ return mp;
+
+freeit:
+ spin_lock(&meta_lock);
+ remove_from_hash(mp, hash_ptr);
+ free_metapage(mp);
+ spin_unlock(&meta_lock);
+ return NULL;
+}
+
+void hold_metapage(struct metapage * mp, int force)
+{
+ spin_lock(&meta_lock);
+
+ mp->count++;
+
+ if (force) {
+ ASSERT (!(test_bit(META_forced, &mp->flag)));
+ if (trylock_metapage(mp))
+ set_bit(META_forced, &mp->flag);
+ } else
+ lock_metapage(mp);
+
+ spin_unlock(&meta_lock);
+}
+
+static void __write_metapage(struct metapage * mp)
+{
+ int l2bsize = mp->mapping->host->i_blkbits;
+ int l2BlocksPerPage = PAGE_CACHE_SHIFT - l2bsize;
+ unsigned long page_index;
+ unsigned long page_offset;
+ int rc;
+
+ jfs_info("__write_metapage: mp = 0x%p", mp);
+
+ page_index = mp->page->index;
+ page_offset =
+ (mp->index - (page_index << l2BlocksPerPage)) << l2bsize;
+
+ lock_page(mp->page);
+ rc = mp->mapping->a_ops->prepare_write(NULL, mp->page, page_offset,
+ page_offset +
+ mp->logical_size);
+ if (rc) {
+ jfs_err("prepare_write return %d!", rc);
+ ClearPageUptodate(mp->page);
+ unlock_page(mp->page);
+ clear_bit(META_dirty, &mp->flag);
+ return;
+ }
+ rc = mp->mapping->a_ops->commit_write(NULL, mp->page, page_offset,
+ page_offset +
+ mp->logical_size);
+ if (rc) {
+ jfs_err("commit_write returned %d", rc);
+ }
+
+ unlock_page(mp->page);
+ clear_bit(META_dirty, &mp->flag);
+
+ jfs_info("__write_metapage done");
+}
+
+static inline void sync_metapage(struct metapage *mp)
+{
+ struct page *page = mp->page;
+
+ page_cache_get(page);
+ lock_page(page);
+
+ /* we're done with this page - no need to check for errors */
+ if (page_has_buffers(page))
+ write_one_page(page, 1);
+ else
+ unlock_page(page);
+ page_cache_release(page);
+}
+
+void release_metapage(struct metapage * mp)
+{
+ struct jfs_log *log;
+
+ jfs_info("release_metapage: mp = 0x%p, flag = 0x%lx", mp, mp->flag);
+
+ spin_lock(&meta_lock);
+ if (test_bit(META_forced, &mp->flag)) {
+ clear_bit(META_forced, &mp->flag);
+ mp->count--;
+ spin_unlock(&meta_lock);
+ return;
+ }
+
+ assert(mp->count);
+ if (--mp->count || atomic_read(&mp->nohomeok)) {
+ unlock_metapage(mp);
+ spin_unlock(&meta_lock);
+ return;
+ }
+
+ if (mp->page) {
+ set_bit(META_stale, &mp->flag);
+ spin_unlock(&meta_lock);
+ kunmap(mp->page);
+ mp->data = NULL;
+ if (test_bit(META_dirty, &mp->flag))
+ __write_metapage(mp);
+ if (test_bit(META_sync, &mp->flag)) {
+ sync_metapage(mp);
+ clear_bit(META_sync, &mp->flag);
+ }
+
+ if (test_bit(META_discard, &mp->flag)) {
+ lock_page(mp->page);
+ block_invalidatepage(mp->page, 0);
+ unlock_page(mp->page);
+ }
+
+ page_cache_release(mp->page);
+ mp->page = NULL;
+ INCREMENT(mpStat.pagefree);
+ spin_lock(&meta_lock);
+ }
+
+ if (mp->lsn) {
+ /*
+ * Remove metapage from logsynclist.
+ */
+ log = mp->log;
+ LOGSYNC_LOCK(log);
+ mp->log = NULL;
+ mp->lsn = 0;
+ mp->clsn = 0;
+ log->count--;
+ list_del(&mp->synclist);
+ LOGSYNC_UNLOCK(log);
+ }
+ remove_from_hash(mp, meta_hash(mp->mapping, mp->index));
+ spin_unlock(&meta_lock);
+
+ free_metapage(mp);
+}
+
+void __invalidate_metapages(struct inode *ip, s64 addr, int len)
+{
+ struct metapage **hash_ptr;
+ unsigned long lblock;
+ int l2BlocksPerPage = PAGE_CACHE_SHIFT - ip->i_blkbits;
+ /* All callers are interested in block device's mapping */
+ struct address_space *mapping = ip->i_sb->s_bdev->bd_inode->i_mapping;
+ struct metapage *mp;
+ struct page *page;
+
+ /*
+ * First, mark metapages to discard. They will eventually be
+ * released, but should not be written.
+ */
+ for (lblock = addr; lblock < addr + len;
+ lblock += 1 << l2BlocksPerPage) {
+ hash_ptr = meta_hash(mapping, lblock);
+again:
+ spin_lock(&meta_lock);
+ mp = search_hash(hash_ptr, mapping, lblock);
+ if (mp) {
+ if (test_bit(META_stale, &mp->flag)) {
+ spin_unlock(&meta_lock);
+ msleep(1);
+ goto again;
+ }
+
+ clear_bit(META_dirty, &mp->flag);
+ set_bit(META_discard, &mp->flag);
+ spin_unlock(&meta_lock);
+ } else {
+ spin_unlock(&meta_lock);
+ page = find_lock_page(mapping, lblock>>l2BlocksPerPage);
+ if (page) {
+ block_invalidatepage(page, 0);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ }
+ }
+}
+
+#ifdef CONFIG_JFS_STATISTICS
+int jfs_mpstat_read(char *buffer, char **start, off_t offset, int length,
+ int *eof, void *data)
+{
+ int len = 0;
+ off_t begin;
+
+ len += sprintf(buffer,
+ "JFS Metapage statistics\n"
+ "=======================\n"
+ "page allocations = %d\n"
+ "page frees = %d\n"
+ "lock waits = %d\n",
+ mpStat.pagealloc,
+ mpStat.pagefree,
+ mpStat.lockwait);
+
+ begin = offset;
+ *start = buffer + begin;
+ len -= begin;
+
+ if (len > length)
+ len = length;
+ else
+ *eof = 1;
+
+ if (len < 0)
+ len = 0;
+
+ return len;
+}
+#endif