Refresh linux-debug-zerocopy

.topdeps

@@ -1 +1 @@
-zfs-branch
+linux-kernel-module

.topmsg

@@ -1,11 +1,6 @@
 From: Brian Behlendorf <behlendorf1@llnl.gov>
-Subject: [PATCH] linux kernel module
+Subject: [PATCH] linux debug zerocopy
 
-Setup linux kernel module support, this includes:
+Add debug ONLY option for zerocopy
-- zfs context for kernel/user
-- kernel module build system integration
-- kernel module macros
-- kernel module symbol export
-- kernel module options
 
 Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

zfs/lib/libzpool/dmu.c

@@ -539,8 +539,8 @@ dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
 }
 
 int
-dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+dmu_read_impl(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
-    void *buf)
+    void *buf, int flags)
 {
 	dnode_t *dn;
 	dmu_buf_t **dbp;
@@ -584,6 +584,7 @@ dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 			bufoff = offset - db->db_offset;
 			tocpy = (int)MIN(db->db_size - bufoff, size);
 
+			if (!(flags & DMU_READ_ZEROCOPY))
 				bcopy((char *)db->db_data + bufoff, buf, tocpy);
 
 			offset += tocpy;
@@ -596,9 +597,16 @@ dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 	return (err);
 }
 
+int
+dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+    void *buf)
+{
+	return dmu_read_impl(os, object, offset, size, buf, 0);
+}
+
 void
-dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+dmu_write_impl(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
-    const void *buf, dmu_tx_t *tx)
+    const void *buf, dmu_tx_t *tx, int flags)
 {
 	dmu_buf_t **dbp;
 	int numbufs, i;
@@ -626,6 +634,7 @@ dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 		else
 			dmu_buf_will_dirty(db, tx);
 
+		if (!(flags & DMU_WRITE_ZEROCOPY))
 			bcopy(buf, (char *)db->db_data + bufoff, tocpy);
 
 		if (tocpy == db->db_size)
@@ -659,6 +668,13 @@ dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 	dmu_buf_rele_array(dbp, numbufs, FTAG);
 }
 
+void
+dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+    const void *buf, dmu_tx_t *tx)
+{
+	dmu_write_impl(os, object, offset, size, buf, tx, 0);
+}
+
 #ifdef _KERNEL
 int
 dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
@@ -1229,7 +1245,9 @@ dmu_fini(void)
 #if defined(_KERNEL) && defined(HAVE_SPL)
 EXPORT_SYMBOL(dmu_bonus_hold);
 EXPORT_SYMBOL(dmu_free_range);
+EXPORT_SYMBOL(dmu_read_impl);
 EXPORT_SYMBOL(dmu_read);
+EXPORT_SYMBOL(dmu_write_impl);
 EXPORT_SYMBOL(dmu_write);
 
 /* Get information on a DMU object. */

zfs/lib/libzpool/include/sys/dmu.h

@@ -156,6 +156,8 @@ void zfs_znode_byteswap(void *buf, size_t size);
  */
 #define DMU_MAX_ACCESS		(10<<20) /* 10MB */
 #define DMU_MAX_DELETEBLKCNT	(20480) /* ~5MB of indirect blocks */
+#define DMU_WRITE_ZEROCOPY	0x0001
+#define DMU_READ_ZEROCOPY	0x0002
 
 /*
  * Public routines to create, destroy, open, and close objsets.
@@ -472,8 +474,12 @@ int dmu_free_object(objset_t *os, uint64_t object);
  * Canfail routines will return 0 on success, or an errno if there is a
  * nonrecoverable I/O error.
  */
+int dmu_read_impl(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+	void *buf, int flags);
 int dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 	void *buf);
+void dmu_write_impl(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
+	const void *buf, dmu_tx_t *tx, int flags);
 void dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 	const void *buf, dmu_tx_t *tx);
 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,