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authorCarsten Otte <cotte@de.ibm.com>2005-06-23 22:05:25 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-24 00:06:41 -0700
commitceffc078528befc008c6f2c2c4decda79eabd534 (patch)
treea289e10162bdef0c0d9f6533f1a647b0fe1ed7a9 /mm/filemap.h
parent420edbcc09008342c7b2665453f6b370739aadb0 (diff)
downloadlinux-sh-ceffc078528befc008c6f2c2c4decda79eabd534.tar.gz
[PATCH] xip: fs/mm: execute in place
- generic_file* file operations do no longer have a xip/non-xip split - filemap_xip.c implements a new set of fops that require get_xip_page aop to work proper. all new fops are exported GPL-only (don't like to see whatever code use those except GPL modules) - __xip_unmap now uses page_check_address, which is no longer static in rmap.c, and defined in linux/rmap.h - mm/filemap.h is now much more clean, plainly having just Linus' inline funcs moved here from filemap.c - fix includes in filemap_xip to make it build cleanly on i386 Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'mm/filemap.h')
-rw-r--r--mm/filemap.h94
1 files changed, 94 insertions, 0 deletions
diff --git a/mm/filemap.h b/mm/filemap.h
new file mode 100644
index 000000000000..c2d0546a57eb
--- /dev/null
+++ b/mm/filemap.h
@@ -0,0 +1,94 @@
+/*
+ * linux/mm/filemap.h
+ *
+ * Copyright (C) 1994-1999 Linus Torvalds
+ */
+
+#ifndef __FILEMAP_H
+#define __FILEMAP_H
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/uio.h>
+#include <linux/config.h>
+#include <asm/uaccess.h>
+
+extern size_t
+__filemap_copy_from_user_iovec(char *vaddr,
+ const struct iovec *iov,
+ size_t base,
+ size_t bytes);
+
+/*
+ * Copy as much as we can into the page and return the number of bytes which
+ * were sucessfully copied. If a fault is encountered then clear the page
+ * out to (offset+bytes) and return the number of bytes which were copied.
+ */
+static inline size_t
+filemap_copy_from_user(struct page *page, unsigned long offset,
+ const char __user *buf, unsigned bytes)
+{
+ char *kaddr;
+ int left;
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ left = __copy_from_user_inatomic(kaddr + offset, buf, bytes);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ if (left != 0) {
+ /* Do it the slow way */
+ kaddr = kmap(page);
+ left = __copy_from_user(kaddr + offset, buf, bytes);
+ kunmap(page);
+ }
+ return bytes - left;
+}
+
+/*
+ * This has the same sideeffects and return value as filemap_copy_from_user().
+ * The difference is that on a fault we need to memset the remainder of the
+ * page (out to offset+bytes), to emulate filemap_copy_from_user()'s
+ * single-segment behaviour.
+ */
+static inline size_t
+filemap_copy_from_user_iovec(struct page *page, unsigned long offset,
+ const struct iovec *iov, size_t base, size_t bytes)
+{
+ char *kaddr;
+ size_t copied;
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ copied = __filemap_copy_from_user_iovec(kaddr + offset, iov,
+ base, bytes);
+ kunmap_atomic(kaddr, KM_USER0);
+ if (copied != bytes) {
+ kaddr = kmap(page);
+ copied = __filemap_copy_from_user_iovec(kaddr + offset, iov,
+ base, bytes);
+ kunmap(page);
+ }
+ return copied;
+}
+
+static inline void
+filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes)
+{
+ const struct iovec *iov = *iovp;
+ size_t base = *basep;
+
+ while (bytes) {
+ int copy = min(bytes, iov->iov_len - base);
+
+ bytes -= copy;
+ base += copy;
+ if (iov->iov_len == base) {
+ iov++;
+ base = 0;
+ }
+ }
+ *iovp = iov;
+ *basep = base;
+}
+#endif