[PATCH V2 5/6] drivers/staging/ramster: ramster-specific new files

[Dan Magenheimer]

New files for ramster support:  The file ramster.h declares externs
and some pampd bitfield manipulation.  The file zcache.h declares
some zcache functions that now must be accessed from the ramster
glue code.  The file ramster_o2net.c is the glue between
zcache and the o2net messaging code, providing routines called
from zcache that initiate messages, and routines that handle
messages by calling zcache.

Signed-off-by: Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>

---

 drivers/staging/ramster/ramster.h       |  117 +++++++++
 drivers/staging/ramster/ramster_o2net.c |  419 +++++++++++++++++++++++++++++++
 drivers/staging/ramster/zcache.h        |   22 ++
 3 files changed, 558 insertions(+), 0 deletions(-)

diff --git a/drivers/staging/ramster/ramster.h b/drivers/staging/ramster/ramster.h
new file mode 100644
index 0000000..3293512
--- /dev/null
+++ b/drivers/staging/ramster/ramster.h
@@ -0,0 +1,117 @@
+/*
+ * ramster.h
+ *
+ * Peer-to-peer transcendent memory
+ *
+ * Copyright (c) 2009-2012, Dan Magenheimer, Oracle Corp.
+ */
+
+#ifndef _RAMSTER_H_
+#define _RAMSTER_H_
+
+/*
+ * format of remote pampd:
+ *   bit 0 == intransit
+ *   bit 1 == is_remote... if this bit is set, then
+ *   bit 2-9 == remotenode
+ *   bit 10-22 == size
+ *   bit 23-30 == cksum
+ */
+#define FAKE_PAMPD_INTRANSIT_BITS	1
+#define FAKE_PAMPD_ISREMOTE_BITS	1
+#define FAKE_PAMPD_REMOTENODE_BITS	8
+#define FAKE_PAMPD_REMOTESIZE_BITS	13
+#define FAKE_PAMPD_CHECKSUM_BITS	8
+
+#define FAKE_PAMPD_INTRANSIT_SHIFT	0
+#define FAKE_PAMPD_ISREMOTE_SHIFT	(FAKE_PAMPD_INTRANSIT_SHIFT + \
+					 FAKE_PAMPD_INTRANSIT_BITS)
+#define FAKE_PAMPD_REMOTENODE_SHIFT	(FAKE_PAMPD_ISREMOTE_SHIFT + \
+					 FAKE_PAMPD_ISREMOTE_BITS)
+#define FAKE_PAMPD_REMOTESIZE_SHIFT	(FAKE_PAMPD_REMOTENODE_SHIFT + \
+					 FAKE_PAMPD_REMOTENODE_BITS)
+#define FAKE_PAMPD_CHECKSUM_SHIFT	(FAKE_PAMPD_REMOTESIZE_SHIFT + \
+					 FAKE_PAMPD_REMOTESIZE_BITS)
+
+#define FAKE_PAMPD_MASK(x)		((1UL << (x)) - 1)
+
+static inline void *pampd_make_remote(int remotenode, size_t size,
+					unsigned char cksum)
+{
+	unsigned long fake_pampd = 0;
+	fake_pampd |= 1UL << FAKE_PAMPD_ISREMOTE_SHIFT;
+	fake_pampd |= ((unsigned long)remotenode &
+			FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTENODE_BITS)) <<
+				FAKE_PAMPD_REMOTENODE_SHIFT;
+	fake_pampd |= ((unsigned long)size &
+			FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTESIZE_BITS)) <<
+				FAKE_PAMPD_REMOTESIZE_SHIFT;
+	fake_pampd |= ((unsigned long)cksum &
+			FAKE_PAMPD_MASK(FAKE_PAMPD_CHECKSUM_BITS)) <<
+				FAKE_PAMPD_CHECKSUM_SHIFT;
+	return (void *)fake_pampd;
+}
+
+static inline unsigned int pampd_remote_node(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+	return (fake_pampd >> FAKE_PAMPD_REMOTENODE_SHIFT) &
+		FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTENODE_BITS);
+}
+
+static inline unsigned int pampd_remote_size(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+	return (fake_pampd >> FAKE_PAMPD_REMOTESIZE_SHIFT) &
+		FAKE_PAMPD_MASK(FAKE_PAMPD_REMOTESIZE_BITS);
+}
+
+static inline unsigned char pampd_remote_cksum(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+	return (fake_pampd >> FAKE_PAMPD_CHECKSUM_SHIFT) &
+		FAKE_PAMPD_MASK(FAKE_PAMPD_CHECKSUM_BITS);
+}
+
+static inline bool pampd_is_remote(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+	return (fake_pampd >> FAKE_PAMPD_ISREMOTE_SHIFT) &
+		FAKE_PAMPD_MASK(FAKE_PAMPD_ISREMOTE_BITS);
+}
+
+static inline bool pampd_is_intransit(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+	return (fake_pampd >> FAKE_PAMPD_INTRANSIT_SHIFT) &
+		FAKE_PAMPD_MASK(FAKE_PAMPD_INTRANSIT_BITS);
+}
+
+/* note that it is a BUG for intransit to be set without isremote also set */
+static inline void *pampd_mark_intransit(void *pampd)
+{
+	unsigned long fake_pampd = (unsigned long)pampd;
+
+	fake_pampd |= 1UL << FAKE_PAMPD_ISREMOTE_SHIFT;
+	fake_pampd |= 1UL << FAKE_PAMPD_INTRANSIT_SHIFT;
+	return (void *)fake_pampd;
+}
+
+static inline void *pampd_mask_intransit_and_remote(void *marked_pampd)
+{
+	unsigned long pampd = (unsigned long)marked_pampd;
+
+	pampd &= ~(1UL << FAKE_PAMPD_INTRANSIT_SHIFT);
+	pampd &= ~(1UL << FAKE_PAMPD_ISREMOTE_SHIFT);
+	return (void *)pampd;
+}
+
+extern int ramster_remote_async_get(struct tmem_xhandle *,
+				bool, int, size_t, uint8_t, void *extra);
+extern int ramster_remote_put(struct tmem_xhandle *, char *, size_t,
+				bool, int *);
+extern int ramster_remote_flush(struct tmem_xhandle *, int);
+extern int ramster_remote_flush_object(struct tmem_xhandle *, int);
+extern int ramster_o2net_register_handlers(void);
+
+#endif /* _TMEM_H */
diff --git a/drivers/staging/ramster/ramster_o2net.c b/drivers/staging/ramster/ramster_o2net.c
new file mode 100644
index 0000000..ee6a9ed
--- /dev/null
+++ b/drivers/staging/ramster/ramster_o2net.c
@@ -0,0 +1,419 @@
+/*
+ * ramster_o2net.c
+ *
+ * Copyright (c) 2011, Dan Magenheimer, Oracle Corp.
+ *
+ * Ramster_o2net provides an interface between zcache and o2net.
+ *
+ * FIXME: support more than two nodes
+ */
+
+#include <linux/list.h>
+#include "cluster/tcp.h"
+#include "cluster/nodemanager.h"
+#include "tmem.h"
+#include "zcache.h"
+#include "ramster.h"
+
+#define RMSTR_KEY	0x77347734
+
+enum {
+	RMSTR_TMEM_PUT_EPH = 100,
+	RMSTR_TMEM_PUT_PERS,
+	RMSTR_TMEM_ASYNC_GET_REQUEST,
+	RMSTR_TMEM_ASYNC_GET_AND_FREE_REQUEST,
+	RMSTR_TMEM_ASYNC_GET_REPLY,
+	RMSTR_TMEM_FLUSH,
+	RMSTR_TMEM_FLOBJ,
+	RMSTR_TMEM_DESTROY_POOL,
+};
+
+#define RMSTR_O2NET_MAX_LEN \
+		(O2NET_MAX_PAYLOAD_BYTES - sizeof(struct tmem_xhandle))
+
+#include "cluster/tcp_internal.h"
+
+static struct o2nm_node *ramster_choose_node(int *nodenum,
+						struct tmem_xhandle *xh)
+{
+	struct o2nm_node *node = NULL;
+	int i;
+
+/* FIXME reproducibly pick a node based on xh that is NOT this node */
+	i = o2nm_this_node();
+	i = !i;		/* FIXME ONLY FOR TWO NODES */
+	node = o2nm_get_node_by_num(i);
+		/* WARNING: THIS DOES NOT CHECK TO ENSURE CONNECTED */
+	if (node != NULL)
+		*nodenum = i;
+	return node;
+}
+
+static void ramster_put_node(struct o2nm_node *node)
+{
+	o2nm_node_put(node);
+}
+
+/* FIXME following buffer should be per-cpu, protected by preempt_disable */
+static char ramster_async_get_buf[O2NET_MAX_PAYLOAD_BYTES];
+
+static int ramster_remote_async_get_request_handler(struct o2net_msg *msg,
+				u32 len, void *data, void **ret_data)
+{
+	char *pdata;
+	struct tmem_xhandle xh;
+	int found;
+	size_t size = RMSTR_O2NET_MAX_LEN;
+	u16 msgtype = be16_to_cpu(msg->msg_type);
+	bool get_and_free = (msgtype == RMSTR_TMEM_ASYNC_GET_AND_FREE_REQUEST);
+	unsigned long flags;
+
+	xh = *(struct tmem_xhandle *)msg->buf;
+	if (xh.xh_data_size > RMSTR_O2NET_MAX_LEN)
+		BUG();
+	pdata = ramster_async_get_buf;
+	*(struct tmem_xhandle *)pdata = xh;
+	pdata += sizeof(struct tmem_xhandle);
+	local_irq_save(flags);
+	found = zcache_get(xh.client_id, xh.pool_id, &xh.oid, xh.index,
+				pdata, &size, 1, get_and_free ? 1 : -1);
+	local_irq_restore(flags);
+	if (found < 0) {
+#if 0
+static unsigned long cnt;
+cnt++;
+if (!(cnt&(cnt-1)))
+pr_err("TESTING ArrgREQ zcache_get %s failed, assuming is this OK? cnt=%lu\n",
+	(get_and_free) ? "eph" : "pers", cnt);
+#endif
+		/* a zero size indicates the get failed */
+		size = 0;
+	}
+	if (size > RMSTR_O2NET_MAX_LEN)
+		BUG();
+#if 0
+if (size != 0) {
+/* DOH! RMSTR_O2NET_MAX_LEN==4032... means zcache_get is returning failure
+   which means maybe a race with a flush? */
+unsigned char cksum;
+int i;
+char *tmp;
+for (tmp = pdata, cksum = 0, i = 0; i < size; i++)
+	cksum += *tmp;
+if ((xh.xh_data_size != size) || (xh.xh_data_cksum != cksum))
+pr_err("TESTING ArrgREQ, HUH xh_data_size=%d, exp=%d, cksum=%d, exp=%d,"
+	"xh=(%d,0x%llx.0x%llx.0x%llx,%x), %s\n",
+	(int)xh.xh_data_size, (int)size, xh.xh_data_cksum, cksum,
+	xh.pool_id, xh.oid.oid[0], xh.oid.oid[1], xh.oid.oid[2],
+	xh.index, (get_and_free ? "eph" : "pers"));
+else {
+#if 0
+static unsigned long cnt;
+cnt++;
+if (!(cnt&(cnt-1)))
+pr_err("TESTING ArrgREQ cnt=%lu, xh_data_size=%d, exp=%d, cksum=%d, exp=%d\n",
+	cnt, (int)xh.xh_data_size, (int)size, xh.xh_data_cksum, cksum);
+#endif
+}
+}
+#endif
+	*ret_data = pdata - sizeof(struct tmem_xhandle);
+	/* now make caller (o2net_process_message) handle specially */
+	o2net_force_data_magic(msg, RMSTR_TMEM_ASYNC_GET_REPLY, RMSTR_KEY);
+	return size + sizeof(struct tmem_xhandle);
+}
+
+static int ramster_remote_async_get_reply_handler(struct o2net_msg *msg,
+				u32 len, void *data, void **ret_data)
+{
+	char *in = (char *)msg->buf;
+	int datalen = len - sizeof(struct o2net_msg);
+	int ret = -1;
+	struct tmem_xhandle *xh = (struct tmem_xhandle *)in;
+
+	in += sizeof(struct tmem_xhandle);
+	datalen -= sizeof(struct tmem_xhandle);
+	BUG_ON(datalen < 0 || datalen > PAGE_SIZE);
+	ret = zcache_localify(xh->pool_id, &xh->oid, xh->index,
+				in, datalen, xh->extra);
+#if 1
+if (ret == -EEXIST)
+pr_err("TESTING ArrgREP, aborted overwrite on racy put\n");
+#endif
+	return ret;
+}
+
+int ramster_remote_put_handler(struct o2net_msg *msg,
+				u32 len, void *data, void **ret_data)
+{
+	struct tmem_xhandle *xh;
+	char *p = (char *)msg->buf;
+	int datalen = len - sizeof(struct o2net_msg) -
+				sizeof(struct tmem_xhandle);
+	u16 msgtype = be16_to_cpu(msg->msg_type);
+	bool ephemeral = (msgtype == RMSTR_TMEM_PUT_EPH);
+	unsigned long flags;
+	int ret;
+
+	xh = (struct tmem_xhandle *)p;
+	p += sizeof(struct tmem_xhandle);
+	zcache_autocreate_pool(xh->client_id, xh->pool_id, ephemeral);
+	local_irq_save(flags);
+	ret = zcache_put(xh->client_id, xh->pool_id, &xh->oid, xh->index,
+				p, datalen, 1, ephemeral ? 1 : -1);
+	local_irq_restore(flags);
+	return ret;
+}
+
+int ramster_remote_flush_handler(struct o2net_msg *msg,
+				u32 len, void *data, void **ret_data)
+{
+	struct tmem_xhandle *xh;
+	char *p = (char *)msg->buf;
+
+	xh = (struct tmem_xhandle *)p;
+	p += sizeof(struct tmem_xhandle);
+	(void)zcache_flush(xh->client_id, xh->pool_id, &xh->oid, xh->index);
+	return 0;
+}
+
+int ramster_remote_flobj_handler(struct o2net_msg *msg,
+				u32 len, void *data, void **ret_data)
+{
+	struct tmem_xhandle *xh;
+	char *p = (char *)msg->buf;
+
+	xh = (struct tmem_xhandle *)p;
+	p += sizeof(struct tmem_xhandle);
+	(void)zcache_flush_object(xh->client_id, xh->pool_id, &xh->oid);
+	return 0;
+}
+
+int ramster_remote_async_get(struct tmem_xhandle *xh, bool free, int remotenode,
+				size_t expect_size, uint8_t expect_cksum,
+				void *extra)
+{
+	int ret = -1, status;
+	struct o2nm_node *node = NULL;
+	struct kvec vec[1];
+	size_t veclen = 1;
+	u32 msg_type;
+
+	node = o2nm_get_node_by_num(remotenode);
+	if (node == NULL)
+		goto out;
+	xh->client_id = o2nm_this_node(); /* which node is getting */
+	xh->xh_data_cksum = expect_cksum;
+	xh->xh_data_size = expect_size;
+	xh->extra = extra;
+	vec[0].iov_len = sizeof(*xh);
+	vec[0].iov_base = xh;
+	if (free)
+		msg_type = RMSTR_TMEM_ASYNC_GET_AND_FREE_REQUEST;
+	else
+		msg_type = RMSTR_TMEM_ASYNC_GET_REQUEST;
+	ret = o2net_send_message_vec(msg_type, RMSTR_KEY,
+					vec, veclen, remotenode, &status);
+	ramster_put_node(node);
+	if (ret < 0) {
+		/* FIXME handle bad message possibilities here? */
+		pr_err("UNTESTED ret<0 in ramster_remote_async_get\n");
+	}
+	ret = status;
+out:
+	return ret;
+}
+
+int ramster_remote_put(struct tmem_xhandle *xh, char *data, size_t size,
+				bool ephemeral, int *remotenode)
+{
+	int nodenum, ret = -1, status;
+	struct o2nm_node *node = NULL;
+	struct kvec vec[2];
+	size_t veclen = 2;
+	u32 msg_type;
+
+	BUG_ON(size > RMSTR_O2NET_MAX_LEN);
+	xh->client_id = o2nm_this_node(); /* which node is putting */
+	vec[0].iov_len = sizeof(*xh);
+	vec[0].iov_base = xh;
+	vec[1].iov_len = size;
+	vec[1].iov_base = data;
+	node = ramster_choose_node(&nodenum, xh);
+	if (!node)
+		goto out;
+
+#if 1
+{
+	extern struct o2net_node *o2net_nn_from_num(u8);
+	struct o2net_node *nn = o2net_nn_from_num(nodenum);
+	WARN_ON_ONCE(nn->nn_persistent_error || !nn->nn_sc_valid);
+}
+#endif
+
+	if (ephemeral)
+		msg_type = RMSTR_TMEM_PUT_EPH;
+	else
+		msg_type = RMSTR_TMEM_PUT_PERS;
+#if 1
+/* leave me here to see if it catches a weird crash I've seen a couple times */
+{
+static int last_hardirq_cnt, last_softirq_cnt, last_preempt_cnt;
+int cur_hardirq_cnt, cur_softirq_cnt, cur_preempt_cnt;
+cur_hardirq_cnt = hardirq_count() >> HARDIRQ_SHIFT;
+if (cur_hardirq_cnt > last_hardirq_cnt) {
+	last_hardirq_cnt = cur_hardirq_cnt;
+	if (!(last_hardirq_cnt&(last_hardirq_cnt-1)))
+		pr_err("TESTING RRP hardirq_count=%d\n", last_hardirq_cnt);
+}
+cur_softirq_cnt = softirq_count() >> SOFTIRQ_SHIFT;
+if (cur_softirq_cnt > last_softirq_cnt) {
+	last_softirq_cnt = cur_softirq_cnt;
+	if (!(last_softirq_cnt&(last_softirq_cnt-1)))
+		pr_err("TESTING RRP softirq_count=%d\n", last_softirq_cnt);
+}
+cur_preempt_cnt = preempt_count() & PREEMPT_MASK;
+if (cur_preempt_cnt > last_preempt_cnt) {
+	last_preempt_cnt = cur_preempt_cnt;
+	if (!(last_preempt_cnt&(last_preempt_cnt-1)))
+		pr_err("TESTING RRP preempt_count=%d\n", last_preempt_cnt);
+}
+}
+#endif
+
+	ret = o2net_send_message_vec(msg_type, RMSTR_KEY,
+						vec, veclen, nodenum, &status);
+#if 1
+	if (ret != 0) {
+		pr_err("UNTESTED case in ramster_remote_put\n");
+		ret = -1;
+	}
+#endif
+	if (ret < 0)
+		ret = -1;
+	else {
+		ret = status;
+		*remotenode = nodenum;
+	}
+
+	ramster_put_node(node);
+out:
+	return ret;
+}
+
+int ramster_remote_flush(struct tmem_xhandle *xh, int remotenode)
+{
+	int ret = -1, status;
+	struct o2nm_node *node = NULL;
+	struct kvec vec[1];
+	size_t veclen = 1;
+
+	node = o2nm_get_node_by_num(remotenode);
+	BUG_ON(node == NULL);
+	xh->client_id = o2nm_this_node(); /* which node is flushing */
+	vec[0].iov_len = sizeof(*xh);
+	vec[0].iov_base = xh;
+	BUG_ON(irqs_disabled());
+	BUG_ON(in_softirq());
+	ret = o2net_send_message_vec(RMSTR_TMEM_FLUSH, RMSTR_KEY,
+					vec, veclen, remotenode, &status);
+	ramster_put_node(node);
+	return ret;
+}
+
+int ramster_remote_flush_object(struct tmem_xhandle *xh, int remotenode)
+{
+	int ret = -1, status;
+	struct o2nm_node *node = NULL;
+	struct kvec vec[1];
+	size_t veclen = 1;
+
+	node = o2nm_get_node_by_num(remotenode);
+	BUG_ON(node == NULL);
+	xh->client_id = o2nm_this_node(); /* which node is flobjing */
+	vec[0].iov_len = sizeof(*xh);
+	vec[0].iov_base = xh;
+	ret = o2net_send_message_vec(RMSTR_TMEM_FLOBJ, RMSTR_KEY,
+					vec, veclen, remotenode, &status);
+	ramster_put_node(node);
+	return ret;
+}
+
+/*
+ * Handler registration
+ */
+
+static LIST_HEAD(ramster_o2net_unreg_list);
+
+static void ramster_o2net_unregister_handlers(void)
+{
+	o2net_unregister_handler_list(&ramster_o2net_unreg_list);
+}
+
+int ramster_o2net_register_handlers(void)
+{
+	int status;
+
+	status = o2net_register_handler(RMSTR_TMEM_PUT_EPH, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_put_handler,
+				NULL, NULL, &ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_PUT_PERS, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_put_handler,
+				NULL, NULL, &ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_ASYNC_GET_REQUEST, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_async_get_request_handler,
+				NULL, NULL,
+				&ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_ASYNC_GET_AND_FREE_REQUEST,
+				RMSTR_KEY, RMSTR_O2NET_MAX_LEN,
+				ramster_remote_async_get_request_handler,
+				NULL, NULL,
+				&ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_ASYNC_GET_REPLY, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_async_get_reply_handler,
+				NULL, NULL,
+				&ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_FLUSH, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_flush_handler,
+				NULL, NULL,
+				&ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	status = o2net_register_handler(RMSTR_TMEM_FLOBJ, RMSTR_KEY,
+				RMSTR_O2NET_MAX_LEN,
+				ramster_remote_flobj_handler,
+				NULL, NULL,
+				&ramster_o2net_unreg_list);
+	if (status)
+		goto bail;
+
+	pr_info("ramster_o2net: handlers registered\n");
+
+bail:
+	if (status) {
+		ramster_o2net_unregister_handlers();
+		pr_err("ramster_o2net: couldn't register handlers\n");
+	}
+	return status;
+}
diff --git a/drivers/staging/ramster/zcache.h b/drivers/staging/ramster/zcache.h
new file mode 100644
index 0000000..250b121
--- /dev/null
+++ b/drivers/staging/ramster/zcache.h
@@ -0,0 +1,22 @@
+/*
+ * zcache.h
+ *
+ * External zcache functions
+ *
+ * Copyright (c) 2009-2012, Dan Magenheimer, Oracle Corp.
+ */
+
+#ifndef _ZCACHE_H_
+#define _ZCACHE_H_
+
+extern int zcache_put(int, int, struct tmem_oid *, uint32_t,
+			char *, size_t, bool, int);
+extern int zcache_autocreate_pool(int, int, bool);
+extern int zcache_get(int, int, struct tmem_oid *, uint32_t,
+			char *, size_t *, bool, int);
+extern int zcache_flush(int, int, struct tmem_oid *, uint32_t);
+extern int zcache_flush_object(int, int, struct tmem_oid *);
+extern int zcache_localify(int, struct tmem_oid *, uint32_t,
+			char *, size_t, void *);
+
+#endif /* _ZCACHE_H */
-- 
1.7.1

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