/*
- * OBDFS Super operations
+ * Lustre Light I/O Page Cache
*
- * This code is issued under the GNU General Public License.
- * See the file COPYING in this distribution
- *
- * Copyright (C) 1996, 1997, Olaf Kirch <okir@monad.swb.de>
- * Copryright (C) 1999 Stelias Computing Inc,
- * (author Peter J. Braam <braam@stelias.com>)
- * Copryright (C) 1999 Seagate Technology Inc.
+ * Copyright (C) 2002, Cluster File Systems, Inc.
*/
#include <linux/lustre_mds.h>
#include <linux/lustre_light.h>
-void ll_change_inode(struct inode *inode);
-
-static int cache_writes = 0;
-
-
-/* page cache support stuff */
-
-
/*
* Add a page to the dirty page list.
*/
}
-
-
-
-
-static kmem_cache_t *ll_pgrq_cachep = NULL;
-
-int ll_init_pgrqcache(void)
-{
- ENTRY;
- if (ll_pgrq_cachep == NULL) {
- CDEBUG(D_CACHE, "allocating ll_pgrq_cache\n");
- ll_pgrq_cachep = kmem_cache_create("ll_pgrq",
- sizeof(struct ll_pgrq),
- 0, SLAB_HWCACHE_ALIGN,
- NULL, NULL);
- if (ll_pgrq_cachep == NULL) {
- EXIT;
- return -ENOMEM;
- } else {
- CDEBUG(D_CACHE, "allocated cache at %p\n",
- ll_pgrq_cachep);
- }
- } else {
- CDEBUG(D_CACHE, "using existing cache at %p\n",
- ll_pgrq_cachep);
- }
- EXIT;
- return 0;
-} /* ll_init_wreqcache */
-
-inline void ll_pgrq_del(struct ll_pgrq *pgrq)
-{
- --ll_cache_count;
- CDEBUG(D_INFO, "deleting page %p from list [count %ld]\n",
- pgrq->rq_page, ll_cache_count);
- list_del(&pgrq->rq_plist);
- OBDClearCachePage(pgrq->rq_page);
- kmem_cache_free(ll_pgrq_cachep, pgrq);
-}
-
-void ll_cleanup_pgrqcache(void)
-{
- ENTRY;
- if (ll_pgrq_cachep != NULL) {
- CDEBUG(D_CACHE, "destroying ll_pgrqcache at %p, count %ld\n",
- ll_pgrq_cachep, ll_cache_count);
- if (kmem_cache_destroy(ll_pgrq_cachep))
- printk(KERN_INFO __FUNCTION__
- ": unable to free all of cache\n");
- ll_pgrq_cachep = NULL;
- } else
- printk(KERN_INFO __FUNCTION__ ": called with NULL pointer\n");
-
- EXIT;
-} /* ll_cleanup_wreqcache */
-
-
-/* called with the list lock held */
-static struct page *ll_find_page_index(struct inode *inode,
- unsigned long index)
-{
- struct list_head *page_list = ll_iplist(inode);
- struct list_head *tmp;
- struct page *page;
-
- ENTRY;
-
- CDEBUG(D_INFO, "looking for inode %ld pageindex %ld\n",
- inode->i_ino, index);
- OIDEBUG(inode);
-
- if (list_empty(page_list)) {
- EXIT;
- return NULL;
- }
- tmp = page_list;
- while ( (tmp = tmp->next) != page_list ) {
- struct ll_pgrq *pgrq;
-
- pgrq = list_entry(tmp, struct ll_pgrq, rq_plist);
- page = pgrq->rq_page;
- if (index == page->index) {
- CDEBUG(D_INFO,
- "INDEX SEARCH found page %p, index %ld\n",
- page, index);
- EXIT;
- return page;
- }
- }
-
- EXIT;
- return NULL;
-} /* ll_find_page_index */
-
-
-/* call and free pages from Linux page cache: called with io lock on inodes */
-int ll_do_vec_wr(struct inode **inodes, obd_count num_io,
- obd_count num_obdos, struct obdo **obdos,
- obd_count *oa_bufs, struct page **pages, char **bufs,
- obd_size *counts, obd_off *offsets, obd_flag *flags)
-{
- int err;
-
- ENTRY;
-
- CDEBUG(D_INFO, "writing %d page(s), %d obdo(s) in vector\n",
- num_io, num_obdos);
- if (obd_debug_level & D_INFO) { /* DEBUGGING */
- int i;
- printk("OBDOS: ");
- for (i = 0; i < num_obdos; i++)
- printk("%ld:0x%p ", (long)obdos[i]->o_id, obdos[i]);
-
- printk("\nPAGES: ");
- for (i = 0; i < num_io; i++)
- printk("0x%p ", pages[i]);
- printk("\n");
- }
-
- err = obd_brw(WRITE, IID(inodes[0]), num_obdos, obdos,
- oa_bufs, pages, counts, offsets, flags);
-
- CDEBUG(D_INFO, "BRW done\n");
- /* release the pages from the page cache */
- while ( num_io > 0 ) {
- --num_io;
- CDEBUG(D_INFO, "calling put_page for %p, index %ld\n",
- pages[num_io], pages[num_io]->index);
- /* PDEBUG(pages[num_io], "do_vec_wr"); */
- put_page(pages[num_io]);
- /* PDEBUG(pages[num_io], "do_vec_wr"); */
- }
- CDEBUG(D_INFO, "put_page done\n");
-
- while ( num_obdos > 0) {
- --num_obdos;
- CDEBUG(D_INFO, "free obdo %ld\n",(long)obdos[num_obdos]->o_id);
- /* copy o_blocks to i_blocks */
- ll_set_size (inodes[num_obdos], obdos[num_obdos]->o_size);
- //ll_to_inode(inodes[num_obdos], obdos[num_obdos]);
- obdo_free(obdos[num_obdos]);
- }
- CDEBUG(D_INFO, "obdo_free done\n");
- EXIT;
- return err;
-}
-
-
-/*
- * Add a page to the write request cache list for later writing.
- * ASYNCHRONOUS write method.
- */
-static int ll_add_page_to_cache(struct inode *inode, struct page *page)
-{
- int err = 0;
- ENTRY;
-
- /* The PG_obdcache bit is cleared by ll_pgrq_del() BEFORE the page
- * is written, so at worst we will write the page out twice.
- *
- * If the page has the PG_obdcache bit set, then the inode MUST be
- * on the superblock dirty list so we don't need to check this.
- * Dirty inodes are removed from the superblock list ONLY when they
- * don't have any more cached pages. It is possible to have an inode
- * with no dirty pages on the superblock list, but not possible to
- * have an inode with dirty pages NOT on the superblock dirty list.
- */
- if (!OBDAddCachePage(page)) {
- struct ll_pgrq *pgrq;
- pgrq = kmem_cache_alloc(ll_pgrq_cachep, SLAB_KERNEL);
- if (!pgrq) {
- OBDClearCachePage(page);
- EXIT;
- return -ENOMEM;
- }
- /* not really necessary since we set all pgrq fields here
- memset(pgrq, 0, sizeof(*pgrq));
- */
-
- pgrq->rq_page = page;
- pgrq->rq_jiffies = jiffies;
- get_page(pgrq->rq_page);
-
- obd_down(&ll_i2sbi(inode)->ll_list_mutex);
- list_add(&pgrq->rq_plist, ll_iplist(inode));
- ll_cache_count++;
- //printk("-- count %d\n", ll_cache_count);
-
- /* If inode isn't already on superblock inodes list, add it.
- *
- * We increment the reference count on the inode to keep it
- * from being freed from memory. This _should_ be an iget()
- * with an iput() in both flush_reqs() and put_inode(), but
- * since put_inode() is called from iput() we can't call iput()
- * again there. Instead we just increment/decrement i_count,
- * which is mostly what iget/iput do for an inode in memory.
- */
- if ( list_empty(ll_islist(inode)) ) {
- atomic_inc(&inode->i_count);
- CDEBUG(D_INFO,
- "adding inode %ld to superblock list %p\n",
- inode->i_ino, ll_slist(inode));
- list_add(ll_islist(inode), ll_slist(inode));
- }
- obd_up(&ll_i2sbi(inode)->ll_list_mutex);
-
- }
-
- /* XXX For testing purposes, we can write out the page here.
- err = ll_flush_reqs(ll_slist(inode), ~0UL);
- */
-
- EXIT;
- return err;
-} /* ll_add_page_to_cache */
-
-void rebalance(void)
-{
- if (ll_cache_count > 60000) {
- printk("-- count %ld\n", ll_cache_count);
- //ll_flush_dirty_pages(~0UL);
- printk("-- count %ld\n", ll_cache_count);
- }
-}
-
/* select between SYNC and ASYNC I/O methods */
int ll_do_writepage(struct page *page, int sync)
{
ENTRY;
/* PDEBUG(page, "WRITEPAGE"); */
- if ( sync )
- err = ll_brw(WRITE, inode, page, 1);
- else {
- err = ll_add_page_to_cache(inode, page);
- CDEBUG(D_INFO, "DO_WR ino: %ld, page %p, err %d, uptodate %d\n",
- inode->i_ino, page, err, Page_Uptodate(page));
- }
-
+ /* XXX everything is synchronous now */
+ err = ll_brw(WRITE, inode, page, 1);
+
if ( !err ) {
SetPageUptodate(page);
set_page_clean(page);
CDEBUG(D_INODE, "commit write ino %ld (end at %Ld) from %d to %d ,ind %ld\n",
inode->i_ino, len, from, to, page->index);
-
- if (cache_writes == 0) {
- rc = ll_commit_page(page, 1, from, to);
- }
+ rc = ll_commit_page(page, 1, from, to);
if (len > inode->i_size) {
ll_set_size(inode, len);
return page;
}
-
-#ifdef EXT2_OBD_DEBUG
- if ((obd_debug_level & D_INFO) && ll_find_page_index(inode, index)) {
- CDEBUG(D_INFO, "OVERWRITE: found dirty page %p, index %ld\n",
- page, page->index);
- }
-#endif
-
err = ll_brw(READ, inode, page, create);
if ( err ) {
git://git.whamcloud.com / fs / lustre-release.git / blobdiff