diff -urN test.orig/drivers/block/loop.c test/drivers/block/loop.c
--- test.orig/drivers/block/loop.c Thu Feb 7 08:13:01 2002
+++ test/drivers/block/loop.c Thu Feb 7 08:36:53 2002
@@ -278,7 +278,7 @@
spin_lock_irq(&lo->lo_lock);
file = lo->lo_backing_file;
spin_unlock_irq(&lo->lo_lock);
- do_generic_file_read(file, &pos, &desc, lo_read_actor);
+ do_generic_file_read(file, &pos, &desc, lo_read_actor, 0);
return desc.error;
}
diff -urN test.orig/include/linux/errno.h test/include/linux/errno.h
--- test.orig/include/linux/errno.h Thu Feb 7 08:12:12 2002
+++ test/include/linux/errno.h Thu Feb 7 08:36:53 2002
@@ -21,6 +21,9 @@
#define EBADTYPE 527 /* Type not supported by server */
#define EJUKEBOX 528 /* Request initiated, but will not complete before timeout */
+/* Defined for TUX async IO */
+#define EWOULDBLOCKIO 530 /* Would block due to block-IO */
+
#endif
#endif
diff -urN test.orig/include/linux/fs.h test/include/linux/fs.h
--- test.orig/include/linux/fs.h Thu Feb 7 08:12:16 2002
+++ test/include/linux/fs.h Thu Feb 7 08:38:28 2002
@@ -794,6 +794,10 @@
* read, write, poll, fsync, readv, writev can be called
* without the big kernel lock held in all filesystems.
*/
+
+#define F_ATOMIC 0x0001
+#define F_OFFSETOK 0x0002
+
struct file_operations {
struct module *owner;
loff_t (*llseek) (struct file *, loff_t, int);
@@ -1487,12 +1491,13 @@
extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
extern ssize_t generic_file_read(struct file *, char *, size_t, loff_t *);
extern ssize_t generic_file_write(struct file *, const char *, size_t, loff_t *);
-extern void do_generic_file_read(struct file *, loff_t *, read_descriptor_t *, read_actor_t);
-extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
-extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
+extern void do_generic_file_read(struct file *, loff_t *, read_descriptor_t *, read_actor_t, int);
+
extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
extern ssize_t generic_read_dir(struct file *, char *, size_t, loff_t *);
extern int generic_file_open(struct inode * inode, struct file * filp);
+extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
+extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
extern struct file_operations generic_ro_fops;
diff -urN test.orig/mm/filemap.c test/mm/filemap.c
--- test.orig/mm/filemap.c Thu Feb 7 08:12:31 2002
+++ test/mm/filemap.c Thu Feb 7 08:36:53 2002
@@ -1139,7 +1139,7 @@
static void generic_file_readahead(int reada_ok,
struct file * filp, struct inode * inode,
- struct page * page)
+ struct page * page, int flags)
{
unsigned long end_index;
unsigned long index = page->index;
@@ -1269,7 +1269,7 @@
* This is really ugly. But the goto's actually try to clarify some
* of the logic when it comes to error handling etc.
*/
-void do_generic_file_read(struct file * filp, loff_t *ppos, read_descriptor_t * desc, read_actor_t actor)
+void do_generic_file_read(struct file * filp, loff_t *ppos, read_descriptor_t * desc, read_actor_t actor, int flags)
{
struct address_space *mapping = filp->f_dentry->d_inode->i_mapping;
struct inode *inode = mapping->host;
@@ -1328,13 +1328,17 @@
end_index = inode->i_size >> PAGE_CACHE_SHIFT;
- if (index > end_index)
+ if (index > end_index) {
+ desc->error = 0;
break;
+ }
nr = PAGE_CACHE_SIZE;
if (index == end_index) {
nr = inode->i_size & ~PAGE_CACHE_MASK;
- if (nr <= offset)
+ if (nr <= offset) {
+ desc->error = 0;
break;
+ }
}
nr = nr - offset;
@@ -1354,7 +1358,7 @@
if (!Page_Uptodate(page))
goto page_not_up_to_date;
- generic_file_readahead(reada_ok, filp, inode, page);
+ generic_file_readahead(reada_ok, filp, inode, page, flags);
page_ok:
/* If users can be writing to this page using arbitrary
* virtual addresses, take care about potential aliasing
@@ -1394,13 +1398,24 @@
* Ok, the page was not immediately readable, so let's try to read ahead while we're at it..
*/
page_not_up_to_date:
- generic_file_readahead(reada_ok, filp, inode, page);
+ generic_file_readahead(reada_ok, filp, inode, page, flags);
if (Page_Uptodate(page))
goto page_ok;
/* Get exclusive access to the page ... */
- lock_page(page);
+ if (flags & F_ATOMIC) {
+ if (TryLockPage(page)) {
+ if (Page_Uptodate(page))
+ goto page_ok;
+ printk("page_not_up_to_date: -EAGAIN\n");
+ desc->error = -EWOULDBLOCKIO;
+ page_cache_release(page);
+ break;
+ }
+ printk("page_not_up_to_date: atomic trylock succeeded\n");
+ } else
+ lock_page(page);
/* Did it get unhashed before we got the lock? */
if (!page->mapping) {
@@ -1424,11 +1439,12 @@
goto page_ok;
/* Again, try some read-ahead while waiting for the page to finish.. */
- generic_file_readahead(reada_ok, filp, inode, page);
- wait_on_page(page);
+ generic_file_readahead(reada_ok, filp, inode, page, flags);
+ if (!(flags & F_ATOMIC))
+ wait_on_page(page);
if (Page_Uptodate(page))
goto page_ok;
- error = -EIO;
+ error = (flags & F_ATOMIC) ? -EWOULDBLOCKIO : -EIO;
}
/* UHHUH! A synchronous read error occurred. Report it */
@@ -1437,6 +1453,11 @@
break;
no_cached_page:
+ if (flags & F_ATOMIC) {
+ spin_unlock(&pagecache_lock);
+ desc->error = -EWOULDBLOCKIO;
+ break;
+ }
/*
* Ok, it wasn't cached, so we need to create a new
* page..
@@ -1608,7 +1629,7 @@
desc.count = count;
desc.buf = buf;
desc.error = 0;
- do_generic_file_read(filp, ppos, &desc, file_read_actor);
+ do_generic_file_read(filp, ppos, &desc, file_read_actor, 0);
retval = desc.written;
if (!retval)
@@ -1733,7 +1754,7 @@
desc.count = count;
desc.buf = (char *) out_file;
desc.error = 0;
- do_generic_file_read(in_file, ppos, &desc, file_send_actor);
+ do_generic_file_read(in_file, ppos, &desc, file_send_actor, 0);
retval = desc.written;
if (!retval)
diff -urN test.orig/net/khttpd/datasending.c test/net/khttpd/datasending.c
--- test.orig/net/khttpd/datasending.c Thu Feb 7 08:13:10 2002
+++ test/net/khttpd/datasending.c Thu Feb 7 08:36:53 2002
@@ -127,7 +127,7 @@
desc.count = ReadSize;
desc.buf = (char *) CurrentRequest->sock;
desc.error = 0;
- do_generic_file_read(CurrentRequest->filp, ppos, &desc, sock_send_actor);
+ do_generic_file_read(CurrentRequest->filp, ppos, &desc, sock_send_actor, 0);
if (desc.written>0)
{
CurrentRequest->BytesSent += desc.written;