/*
* OBDFS Super operations
*
+ * 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.
#include <linux/smp_lock.h>
#include <linux/obd_support.h>
-#include <linux/obd_sim.h>
+#include <linux/obd_ext2.h>
#include <linux/obdfs.h>
int console_loglevel;
-/* VFS super_block ops */
-
-#if 0
-int obdfs_brw(struct inode *dir, int rw, struct page *page, int create)
+/* SYNCHRONOUS I/O for an inode */
+int obdfs_brw(int rw, struct inode *inode, struct page *page, int create)
{
- return iops(dir)->o_brw(rw, iid(dir), dir, page, create);
+ struct obdo *obdo;
+ int res;
+
+ obdo = obdo_alloc();
+ if ( ! obdo ) {
+ EXIT;
+ return -ENOMEM;
+ }
+
+ obdo->o_id = inode->i_ino;
+
+ res = IOPS(inode, brw)(rw, IID(inode), obdo,
+ (char *)page_address(page),
+ PAGE_SIZE,
+ (page->index) >> PAGE_SHIFT,
+ create);
+
+ obdo_to_inode(inode, obdo); /* copy o_blocks to i_blocks */
+ obdo_free(obdo);
+
+ if ( res == PAGE_SIZE )
+ res = 0;
+ return res;
}
-#endif
/* returns the page unlocked, but with a reference */
int obdfs_readpage(struct dentry *dentry, struct page *page)
int rc;
ENTRY;
- /* XXX flush stuff */
PDEBUG(page, "READ");
- rc = iops(inode)->o_brw(READ, iid(inode),inode, page, 0);
- if (rc == PAGE_SIZE ) {
+ rc = obdfs_brw(READ, inode, page, 0);
+ if (!rc) {
SetPageUptodate(page);
UnlockPage(page);
}
PDEBUG(page, "READ");
- if ( rc == PAGE_SIZE )
- rc = 0;
+ EXIT;
return rc;
+}
+
+static kmem_cache_t *obdfs_wreq_cachep;
+int obdfs_init_wreqcache(void)
+{
+ /* XXX need to free this somewhere? */
+ ENTRY;
+ obdfs_wreq_cachep = kmem_cache_create("obdfs_wreq",
+ sizeof(struct obdfs_wreq),
+ 0, SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (obdfs_wreq_cachep == NULL) {
+ EXIT;
+ return -ENOMEM;
+ }
+ EXIT;
+ return 0;
}
-/* returns the page unlocked, but with a reference */
-static int obdfs_writepage(struct dentry *dentry, struct page *page)
+void obdfs_cleanup_wreqcache(void)
+{
+ if (obdfs_wreq_cachep != NULL)
+ kmem_cache_destroy(obdfs_wreq_cachep);
+
+ obdfs_wreq_cachep = NULL;
+}
+
+
+/*
+ * Find a specific page in the page cache. If it is found, we return
+ * the write request struct associated with it, if not found return NULL.
+ */
+static struct obdfs_wreq *
+obdfs_find_in_page_cache(struct inode *inode, struct page *page)
{
- struct inode *inode = dentry->d_inode;
+ struct list_head *list_head = &OBD_LIST(inode);
+ struct obdfs_wreq *head, *wreq;
+
+ ENTRY;
+ CDEBUG(D_INODE, "looking for inode %ld page %p\n", inode->i_ino, page);
+ if (list_empty(list_head)) {
+ CDEBUG(D_INODE, "empty list\n");
+ EXIT;
+ return NULL;
+ }
+ wreq = head = WREQ(list_head->next);
+ do {
+ CDEBUG(D_INODE, "checking page %p\n", wreq->wb_page);
+ if (wreq->wb_page == page) {
+ CDEBUG(D_INODE, "found page %p in list\n", page);
+ EXIT;
+ return wreq;
+ }
+ } while ((wreq = WB_NEXT(wreq)) != head);
+
+ EXIT;
+ return NULL;
+}
+
+
+/*
+ * Remove a writeback request from a list
+ */
+static inline int
+obdfs_remove_from_page_cache(struct obdfs_wreq *wreq)
+{
+ struct inode *inode = wreq->wb_inode;
+ struct page *page = wreq->wb_page;
int rc;
- ENTRY;
- PDEBUG(page, "WRITEPAGE");
- /* XXX flush stuff */
+ ENTRY;
+ CDEBUG(D_INODE, "removing inode %ld page %p, wreq: %p\n",
+ inode->i_ino, page, wreq);
+ rc = obdfs_brw(WRITE, inode, page, 1);
+ /* XXX probably should handle error here somehow. I think that
+ * ext2 also does the same thing - discard write even if error?
+ */
+ put_page(page);
+ list_del(&wreq->wb_list);
+ kmem_cache_free(obdfs_wreq_cachep, wreq);
+
+ EXIT;
+ return rc;
+}
- rc = iops(inode)->o_brw(WRITE, iid(inode), inode, page, 1);
+/*
+ * Add a page to the write request cache list for later writing
+ */
+static int
+obdfs_add_to_page_cache(struct inode *inode, struct page *page)
+{
+ struct obdfs_wreq *wreq;
- SetPageUptodate(page);
+ ENTRY;
+ wreq = kmem_cache_alloc(obdfs_wreq_cachep, SLAB_KERNEL);
+ CDEBUG(D_INODE, "adding inode %ld page %p, wreq: %p\n",
+ inode->i_ino, page, wreq);
+ if (!wreq) {
+ EXIT;
+ return -ENOMEM;
+ }
+ memset(wreq, 0, sizeof(*wreq));
+
+ wreq->wb_page = page;
+ wreq->wb_inode = inode;
+
+ get_page(wreq->wb_page);
+ list_add(&wreq->wb_list, &OBD_LIST(inode));
+
+ /* For testing purposes, we write out the page here.
+ * In the future, a flush daemon will write out the page.
+ */
+ wreq = obdfs_find_in_page_cache(inode, page);
+ if (!wreq) {
+ CDEBUG(D_INODE, "XXXX Can't find page after adding it!!!\n");
+ return -EINVAL;
+ } else
+ return obdfs_remove_from_page_cache(wreq);
+
+ return 0;
+}
+
+
+int obdfs_do_writepage(struct inode *inode, struct page *page, int sync)
+{
+ int rc;
+
+ ENTRY;
+ PDEBUG(page, "WRITEPAGE");
+ if ( sync ) {
+ rc = obdfs_brw(WRITE, inode, page, 1);
+ } else {
+ /* XXX flush stuff */
+ rc = obdfs_add_to_page_cache(inode, page);
+ }
+
+ if (!rc)
+ SetPageUptodate(page);
PDEBUG(page,"WRITEPAGE");
return rc;
}
+/* returns the page unlocked, but with a reference */
+int obdfs_writepage(struct dentry *dentry, struct page *page)
+{
+ return obdfs_do_writepage(dentry->d_inode, page, 0);
+}
+
/*
* This does the "real" work of the write. The generic routine has
* allocated the page, locked it, done all the page alignment stuff
ENTRY;
if ( !Page_Uptodate(page) ) {
- status = iops(inode)->o_brw(READ, iid(inode), inode, page, 1);
- if (status == PAGE_SIZE ) {
+ status = obdfs_brw(READ, inode, page, 1);
+ if (!status) {
SetPageUptodate(page);
} else {
return status;
status = -EFAULT;
if (bytes) {
-
lock_kernel();
status = obdfs_writepage(file->f_dentry, page);
unlock_kernel();
return bytes;
}
-
-
-
-
-void report_inode(struct page * page) {
- struct inode *inode = (struct inode *)0;
- int offset = (int)&inode->i_data;
- inode = (struct inode *)( (char *)page->mapping - offset);
- if ( inode->i_sb->s_magic == 0x4711 )
- printk("----> ino %ld , dev %d\n", inode->i_ino, inode->i_dev);
-}
-
/*
return an up to date page:
- if locked is true then is returned locked
hash = page_hash(&inode->i_data, offset);
page = grab_cache_page(&inode->i_data, offset);
+ /* Yuck, no page */
+ if (! page) {
+ printk("grab_cache_page says no dice ...\n");
+ return 0;
+ }
+
PDEBUG(page, "GETPAGE: got page - before reading\n");
/* now check if the data in the page is up to date */
if ( Page_Uptodate(page)) {
return page;
}
- /* it's not: read it */
- if (! page) {
- printk("get_page_map says no dice ...\n");
- return 0;
- }
+ rc = obdfs_brw(READ, inode, page, create);
- rc = iops(inode)->o_brw(READ, iid(inode), inode, page, create);
if ( rc != PAGE_SIZE ) {
SetPageError(page);
UnlockPage(page);
}
-struct file_operations obdfs_file_ops = {
- NULL, /* lseek - default */
- generic_file_read, /* read */
- obdfs_file_write, /* write - bad */
- obdfs_readdir, /* readdir */
- NULL, /* poll - default */
- NULL, /* ioctl */
- NULL, /* mmap */
- NULL, /* no special open code */
- NULL, /* flush */
- NULL, /* no special release code */
- NULL, /* fsync */
- NULL, /* fasync */
- NULL, /* check_media_change */
- NULL /* revalidate */
-};
-
-struct inode_operations obdfs_inode_ops = {
- &obdfs_file_ops, /* default directory file-ops */
- obdfs_create, /* create */
- obdfs_lookup, /* lookup */
- obdfs_link, /* link */
- obdfs_unlink, /* unlink */
- obdfs_symlink, /* symlink */
- obdfs_mkdir, /* mkdir */
- obdfs_rmdir, /* rmdir */
- obdfs_mknod, /* mknod */
- obdfs_rename, /* rename */
- obdfs_readlink, /* readlink */
- NULL, /* follow_link */
- NULL, /* get_block */
- obdfs_readpage, /* readpage */
- obdfs_writepage,/* writepage */
- NULL, /* truncate */
- NULL, /* permission */
- NULL /* revalidate */
-};
git://git.whamcloud.com / fs / lustre-release.git / blobdiff