Description: Fix source to compile on 3.19 kernels
Author: Stefan Bader <stefan.bader@canonical.com>
Forward: no

Fixes below inconsistent crash when trying to login to iSCSI target
server, observed with linux kernel v4.1.

-- snip --
CPU: 1 PID: 29883 Comm: istd1 Tainted: G           O    4.1.35-rt40-yocto-standard #1
Hardware name: To be filled by O.E.M. To be filled by O.E.M./Larne CRB, BIOS 4.6.5.4 09/18/2014
task: ffff88020f1f30c0 ti: ffff8800d7f3c000 task.ti: ffff8800d7f3c000
RIP: 0010:[<ffffffff8140d1ae>]  [<ffffffff8140d1ae>] copy_to_iter+0x3e/0x280
RSP: 0018:ffff8800d7f3f728  EFLAGS: 00010246
RAX: 00000000d7f3f928 RBX: 0000000000000030 RCX: 0000000000000030
RDX: ffff8800d7f3f900 RSI: 0000000000000030 RDI: ffff8800d1501e82
RBP: ffff8800d7f3f768 R08: 00000000c127d467 R09: 0000000000000000
R10: ffff88020f29e118 R11: 0000000000000004 R12: ffff8800d7f3f900
R13: 0000000000000030 R14: 0000000000000001 R15: 0000000000000246
FS:  00007f86f9c4c700(0000) GS:ffff88021ec80000(0000) knlGS:00000000f7733700
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000000024e CR3: 00000000d38b0000 CR4: 00000000000406e0
Stack:
ffff880214f14ec0 ffff8800d1501e82 ffff8800d7f3f748 0000000000000030
ffff88020f122500 0000000000000030 0000000000000000 0000000000000030
ffff8800d7f3f7c8 ffffffff81806981 ffff8800d7f3f798 ffffffff8105d72a
Call Trace:
[<ffffffff81806981>] skb_copy_datagram_iter+0x71/0x2b0
[<ffffffff8105d72a>] ? __local_bh_enable_ip+0x4a/0xb0
[<ffffffff8186c9c0>] tcp_recvmsg+0x5e0/0xbb0
[<ffffffff81898ded>] inet_recvmsg+0x8d/0xb0
[<ffffffff817f49f3>] sock_recvmsg+0x13/0x20
[<ffffffffa01655c3>] do_recv+0xe3/0x1f0 [iscsi_trgt]
[<ffffffff81153097>] ? __mod_zone_page_state+0x77/0xb0
[<ffffffff81417613>] ? __this_cpu_preempt_check+0x13/0x20
[<ffffffff81153097>] ? __mod_zone_page_state+0x77/0xb0
[<ffffffff8140fed5>] ? find_next_bit+0x15/0x30
[<ffffffff813fa8e0>] ? cpumask_next_and+0x30/0x50
[<ffffffff8113f785>] ? __alloc_pages_nodemask+0x165/0x980
[<ffffffff8107e370>] ? preempt_count_add+0xd0/0xf0
[<ffffffff8195da8b>] ? _raw_spin_lock+0x1b/0x60
[<ffffffff8109cfa8>] ? cpuacct_charge+0x58/0x70
[<ffffffff81089039>] ? update_curr+0xb9/0x190
[<ffffffff81417613>] ? __this_cpu_preempt_check+0x13/0x20
[<ffffffff8112b43f>] ? __perf_event_task_sched_in+0x4f/0x90
[<ffffffff8195dbbd>] ? _raw_spin_unlock_irq+0x1d/0x40
[<ffffffff8107e223>] ? finish_task_switch+0x63/0xe0
[<ffffffff81959e3b>] ? __schedule+0x38b/0x980
[<ffffffff8107e370>] ? preempt_count_add+0xd0/0xf0
[<ffffffffa0165c65>] istd+0x4d5/0x1390 [iscsi_trgt]
[<ffffffff81959e3b>] ? __schedule+0x38b/0x980
[<ffffffffa0165790>] ? nthread_wakeup+0x40/0x40 [iscsi_trgt]
[<ffffffffa0165790>] ? nthread_wakeup+0x40/0x40 [iscsi_trgt]
[<ffffffff8107748b>] kthread+0xbb/0xe0
[<ffffffff81950000>] ? wireless_dev_seq_show+0x100/0x180
[<ffffffff810773d0>] ? kthread_worker_fn+0x170/0x170
[<ffffffff8195e7a2>] ret_from_fork+0x42/0x70
[<ffffffff810773d0>] ? kthread_worker_fn+0x170/0x170
Code: 5a 10 48 89 7d c8 48 39 f3 48 0f 47 de 48 85 db 0f 84 6f 01 00 00 8b 02 49 89
d4 4c 8b 72 08 4c 8b 7a 18 a8 04 0f 85 a2 00 00 00 <4d> 8b 6f 08 4d 29 f5 49 39 dd 4c 0f 47 eb a8 02 0f 85 5c 01 00 
RSP <ffff8800d7f3f728>
CR2: 000000000000024e
------------[ cut here ]------------
-- snip --

The original patch is at
http://launchpadlibrarian.net/218100509/iscsitarget_1.4.20.3+svn499-0ubuntu2_1.4.20.3+svn499-0ubuntu2.1.diff.gz,
those changes were taken using #ifs, inorder to allow compilation of 
iscsitarget package with linux kernels < 3.19.

Upstream-Status: Submitted [http://launchpadlibrarian.net/218100509/iscsitarget_1.4.20.3+svn499-0ubuntu2_1.4.20.3+svn499-0ubuntu2.1.diff.gz]

Signed-off-by: Jagadeesh Krishnanjanappa <jkrishnanjanappa@mvista.com>

diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/conn.c iscsitarget-1.4.20.3+svn502/kernel/conn.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/conn.c	2017-01-18 22:27:02.713167436 -0800
+++ iscsitarget-1.4.20.3+svn502/kernel/conn.c	2017-01-18 23:13:11.909214379 -0800
@@ -129,7 +129,11 @@ static void iet_socket_bind(struct iscsi
 
 	dprintk(D_GENERIC, "%llu\n", (unsigned long long) session->sid);
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	conn->sock = SOCKET_I(file_inode(conn->file));
+#else
 	conn->sock = SOCKET_I(conn->file->f_dentry->d_inode);
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 	conn->sock->sk->sk_user_data = conn;
 
 	write_lock_bh(&conn->sock->sk->sk_callback_lock);
diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/file-io.c iscsitarget-1.4.20.3+svn502/kernel/file-io.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/file-io.c	2014-05-06 13:59:55.000000000 -0700
+++ iscsitarget-1.4.20.3+svn502/kernel/file-io.c	2017-01-18 23:54:38.505717079 -0800
@@ -69,7 +69,11 @@ static int fileio_make_request(struct ie
 static int fileio_sync(struct iet_volume *lu, struct tio *tio)
 {
 	struct fileio_data *p = lu->private;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	struct inode *inode = file_inode(p->filp);
+#else
 	struct inode *inode = p->filp->f_dentry->d_inode;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 	struct address_space *mapping = inode->i_mapping;
 	loff_t ppos, count;
 	int res;
@@ -213,7 +217,11 @@ static int fileio_attach(struct iet_volu
 		eprintk("%d\n", err);
 		goto out;
 	}
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	inode = file_inode(p->filp);
+#else
 	inode = p->filp->f_dentry->d_inode;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 
 	if (S_ISREG(inode->i_mode))
 		;
diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/iscsi.c iscsitarget-1.4.20.3+svn502/kernel/iscsi.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/iscsi.c	2014-05-06 13:59:55.000000000 -0700
+++ iscsitarget-1.4.20.3+svn502/kernel/iscsi.c	2017-01-18 23:37:36.462970326 -0800
@@ -489,8 +489,12 @@ static void cmnd_skip_pdu(struct iscsi_c
 	}
 	conn->read_iov[i].iov_base = addr;
 	conn->read_iov[i].iov_len = size;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	iov_iter_init(&conn->read_msg.msg_iter, READ, conn->read_iov, ++i, conn->read_size);
+#else
 	conn->read_msg.msg_iov = conn->read_iov;
 	conn->read_msg.msg_iovlen = ++i;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 }
 
 static void iscsi_cmnd_reject(struct iscsi_cmnd *req, int reason)
@@ -718,7 +722,9 @@ static int cmnd_recv_pdu(struct iscsi_co
 	idx = offset >> PAGE_CACHE_SHIFT;
 	offset &= ~PAGE_CACHE_MASK;
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0)
 	conn->read_msg.msg_iov = conn->read_iov;
+#endif	/* LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0) */
 	conn->read_size = size = (size + 3) & -4;
 	conn->read_overflow = 0;
 
@@ -730,16 +736,25 @@ static int cmnd_recv_pdu(struct iscsi_co
 		conn->read_iov[i].iov_base =  addr + offset;
 		if (offset + size <= PAGE_CACHE_SIZE) {
 			conn->read_iov[i].iov_len = size;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+			iov_iter_init(&conn->read_msg.msg_iter, READ, conn->read_iov, ++i, conn->read_size);
+#else
 			conn->read_msg.msg_iovlen = ++i;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 			break;
 		}
 		conn->read_iov[i].iov_len = PAGE_CACHE_SIZE - offset;
 		size -= conn->read_iov[i].iov_len;
 		offset = 0;
 		if (++i >= ISCSI_CONN_IOV_MAX) {
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0)
 			conn->read_msg.msg_iovlen = i;
+#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0) */
 			conn->read_overflow = size;
 			conn->read_size -= size;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+			iov_iter_init(&conn->read_msg.msg_iter, READ, conn->read_iov, i, conn->read_size);
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 			break;
 		}
 
@@ -918,7 +933,9 @@ static int nop_out_start(struct iscsi_co
 
 	if ((size = cmnd->pdu.datasize)) {
 		size = (size + 3) & -4;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0)
 		conn->read_msg.msg_iov = conn->read_iov;
+#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0) */
 		if (cmnd->pdu.bhs.itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
 			struct tio *tio;
 			int pg_cnt = get_pgcnt(size);
@@ -946,7 +963,11 @@ static int nop_out_start(struct iscsi_co
 		}
 		assert(!size);
 		conn->read_overflow = size;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+		iov_iter_init(&conn->read_msg.msg_iter, READ, conn->read_iov, i, conn->read_size);
+#else
 		conn->read_msg.msg_iovlen = i;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 	}
 
 out:
@@ -986,7 +1007,11 @@ static void scsi_cmnd_start(struct iscsi
 		set_cmnd_lunit(req);
 
 	switch (req_hdr->scb[0]) {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	case SERVICE_ACTION_IN_16:
+#else
 	case SERVICE_ACTION_IN:
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 		if ((req_hdr->scb[1] & 0x1f) != 0x10)
 			goto error;
 	case INQUIRY:
diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/nthread.c iscsitarget-1.4.20.3+svn502/kernel/nthread.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/nthread.c	2014-05-06 13:59:55.000000000 -0700
+++ iscsitarget-1.4.20.3+svn502/kernel/nthread.c	2017-01-18 23:45:03.291033881 -0800
@@ -42,9 +42,14 @@ static inline void iscsi_conn_init_read(
 	len = (len + 3) & -4; // XXX ???
 	conn->read_iov[0].iov_base = data;
 	conn->read_iov[0].iov_len = len;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0)
 	conn->read_msg.msg_iov = conn->read_iov;
 	conn->read_msg.msg_iovlen = 1;
+#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3, 19, 0) */
 	conn->read_size = (len + 3) & -4;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	iov_iter_init(&conn->read_msg.msg_iter, READ, conn->read_iov, 1, conn->read_size);
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 }
 
 static void iscsi_conn_read_ahs(struct iscsi_conn *conn, struct iscsi_cmnd *cmnd)
@@ -83,14 +88,31 @@ static int is_data_available(struct iscs
 
 static void forward_iov(struct msghdr *msg, int len)
 {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	struct iovec *iov;
+
+	while (msg->msg_iter.iov->iov_len <= len) {
+		len -= msg->msg_iter.iov->iov_len;
+		msg->msg_iter.iov++;
+		msg->msg_iter.nr_segs--;
+	}
+#else
 	while (msg->msg_iov->iov_len <= len) {
 		len -= msg->msg_iov->iov_len;
 		msg->msg_iov++;
 		msg->msg_iovlen--;
 	}
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	/* XXX: discards const ... */
+	iov = msg->msg_iter.iov;
+	iov->iov_base = (char *) msg->msg_iter.iov->iov_base + len;
+	iov->iov_len -= len;
+#else
 	msg->msg_iov->iov_base = (char *) msg->msg_iov->iov_base + len;
 	msg->msg_iov->iov_len -= len;
+#endif	/* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 }
 
 static int do_recv(struct iscsi_conn *conn, int state)
@@ -98,6 +120,9 @@ static int do_recv(struct iscsi_conn *co
 	mm_segment_t oldfs;
 	struct msghdr msg;
 	struct iovec iov[ISCSI_CONN_IOV_MAX];
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	size_t iovlen = ISCSI_CONN_IOV_MAX;
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 	int i, len, res;
 
 	if (!test_bit(CONN_ACTIVE, &conn->state)) {
@@ -110,12 +135,23 @@ static int do_recv(struct iscsi_conn *co
 		goto out;
 	}
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	if (conn->read_msg.msg_iter.nr_segs < iovlen)
+		iovlen = conn->read_msg.msg_iter.nr_segs;
+
+	for (i = 0, len = 0; i < iovlen; i++) {
+		iov[i] = conn->read_msg.msg_iter.iov[i];
+		len += iov[i].iov_len;
+	}
+	iov_iter_init(&msg.msg_iter, READ, iov, iovlen, len);
+#else
 	msg.msg_iov = iov;
 	msg.msg_iovlen = min_t(size_t, conn->read_msg.msg_iovlen, ISCSI_CONN_IOV_MAX);
 	for (i = 0, len = 0; i < msg.msg_iovlen; i++) {
 		iov[i] = conn->read_msg.msg_iov[i];
 		len += iov[i].iov_len;
 	}
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 
 	oldfs = get_fs();
 	set_fs(get_ds());
diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/target_disk.c iscsitarget-1.4.20.3+svn502/kernel/target_disk.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/target_disk.c	2014-05-06 13:59:55.000000000 -0700
+++ iscsitarget-1.4.20.3+svn502/kernel/target_disk.c	2017-01-18 23:45:51.451010417 -0800
@@ -606,7 +606,11 @@ static int disk_execute_cmnd(struct iscs
 	case REQUEST_SENSE:
 		send_data_rsp(cmnd, build_request_sense_response);
 		break;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	case SERVICE_ACTION_IN_16:
+#else
 	case SERVICE_ACTION_IN:
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 		send_data_rsp(cmnd, build_service_action_in_response);
 		break;
 	case READ_6:
diff -Naurp iscsitarget-1.4.20.3+svn502_org/kernel/volume.c iscsitarget-1.4.20.3+svn502/kernel/volume.c
--- iscsitarget-1.4.20.3+svn502_org/kernel/volume.c	2014-05-06 13:59:55.000000000 -0700
+++ iscsitarget-1.4.20.3+svn502/kernel/volume.c	2017-01-18 23:47:07.957561600 -0800
@@ -398,7 +398,11 @@ int is_volume_reserved(struct iet_volume
 		case READ_CAPACITY:
 			/* allowed commands when reserved */
 			break;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+		case SERVICE_ACTION_IN_16:
+#else
 		case SERVICE_ACTION_IN:
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 			if ((scb[1] & 0x1F) == 0x10)
 				break;
 			/* fall through */
@@ -465,7 +469,11 @@ int is_volume_reserved(struct iet_volume
 		if (excl_access_ro && !registered)
 			err = -EBUSY;
 		break;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0)
+	case SERVICE_ACTION_IN_16:
+#else
 	case SERVICE_ACTION_IN:
+#endif /* LINUX_VERSION_CODE >= KERNEL_VERSION(3, 19, 0) */
 		if ((scb[1] & 0x1F) == 0x10)
 			break;
 		/* fall through */