From 863981e96738983919de841ec669e157e6bdaeb0 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Sun, 11 Sep 2016 04:34:46 -0300
Subject: Linux-libre 4.7.1-gnu

---
 drivers/s390/block/dasd.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 91 insertions(+), 1 deletion(-)

(limited to 'drivers/s390/block/dasd.c')

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index c78db05e7..8973d34ce 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -75,6 +75,8 @@ static void dasd_block_timeout(unsigned long);
 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
 static void dasd_profile_exit(struct dasd_profile *);
+static void dasd_hosts_init(struct dentry *, struct dasd_device *);
+static void dasd_hosts_exit(struct dasd_device *);
 
 /*
  * SECTION: Operations on the device structure.
@@ -267,6 +269,7 @@ static int dasd_state_known_to_basic(struct dasd_device *device)
 		dasd_debugfs_setup(dev_name(&device->cdev->dev),
 				   dasd_debugfs_root_entry);
 	dasd_profile_init(&device->profile, device->debugfs_dentry);
+	dasd_hosts_init(device->debugfs_dentry, device);
 
 	/* register 'device' debug area, used for all DBF_DEV_XXX calls */
 	device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
@@ -304,6 +307,7 @@ static int dasd_state_basic_to_known(struct dasd_device *device)
 		return rc;
 	dasd_device_clear_timer(device);
 	dasd_profile_exit(&device->profile);
+	dasd_hosts_exit(device);
 	debugfs_remove(device->debugfs_dentry);
 	DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
 	if (device->debug_area != NULL) {
@@ -1150,6 +1154,58 @@ int dasd_profile_on(struct dasd_profile *profile)
 
 #endif				/* CONFIG_DASD_PROFILE */
 
+static int dasd_hosts_show(struct seq_file *m, void *v)
+{
+	struct dasd_device *device;
+	int rc = -EOPNOTSUPP;
+
+	device = m->private;
+	dasd_get_device(device);
+
+	if (device->discipline->hosts_print)
+		rc = device->discipline->hosts_print(device, m);
+
+	dasd_put_device(device);
+	return rc;
+}
+
+static int dasd_hosts_open(struct inode *inode, struct file *file)
+{
+	struct dasd_device *device = inode->i_private;
+
+	return single_open(file, dasd_hosts_show, device);
+}
+
+static const struct file_operations dasd_hosts_fops = {
+	.owner		= THIS_MODULE,
+	.open		= dasd_hosts_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static void dasd_hosts_exit(struct dasd_device *device)
+{
+	debugfs_remove(device->hosts_dentry);
+	device->hosts_dentry = NULL;
+}
+
+static void dasd_hosts_init(struct dentry *base_dentry,
+			    struct dasd_device *device)
+{
+	struct dentry *pde;
+	umode_t mode;
+
+	if (!base_dentry)
+		return;
+
+	mode = S_IRUSR | S_IFREG;
+	pde = debugfs_create_file("host_access_list", mode, base_dentry,
+				  device, &dasd_hosts_fops);
+	if (pde && !IS_ERR(pde))
+		device->hosts_dentry = pde;
+}
+
 /*
  * Allocate memory for a channel program with 'cplength' channel
  * command words and 'datasize' additional space. There are two
@@ -1582,6 +1638,9 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
 	struct dasd_ccw_req *cqr, *next;
 	struct dasd_device *device;
 	unsigned long long now;
+	int nrf_suppressed = 0;
+	int fp_suppressed = 0;
+	u8 *sense = NULL;
 	int expires;
 
 	if (IS_ERR(irb)) {
@@ -1617,7 +1676,23 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
 			dasd_put_device(device);
 			return;
 		}
-		device->discipline->dump_sense_dbf(device, irb, "int");
+
+		/*
+		 * In some cases 'File Protected' or 'No Record Found' errors
+		 * might be expected and debug log messages for the
+		 * corresponding interrupts shouldn't be written then.
+		 * Check if either of the according suppress bits is set.
+		 */
+		sense = dasd_get_sense(irb);
+		if (sense) {
+			fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) &&
+				test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags);
+			nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) &&
+				test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags);
+		}
+		if (!(fp_suppressed || nrf_suppressed))
+			device->discipline->dump_sense_dbf(device, irb, "int");
+
 		if (device->features & DASD_FEATURE_ERPLOG)
 			device->discipline->dump_sense(device, cqr, irb);
 		device->discipline->check_for_device_change(device, cqr, irb);
@@ -2256,6 +2331,7 @@ static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible)
 {
 	struct dasd_device *device;
 	struct dasd_ccw_req *cqr, *n;
+	u8 *sense = NULL;
 	int rc;
 
 retry:
@@ -2301,6 +2377,20 @@ retry:
 
 	rc = 0;
 	list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
+		/*
+		 * In some cases the 'File Protected' or 'Incorrect Length'
+		 * error might be expected and error recovery would be
+		 * unnecessary in these cases.	Check if the according suppress
+		 * bit is set.
+		 */
+		sense = dasd_get_sense(&cqr->irb);
+		if (sense && sense[1] & SNS1_FILE_PROTECTED &&
+		    test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags))
+			continue;
+		if (scsw_cstat(&cqr->irb.scsw) == 0x40 &&
+		    test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags))
+			continue;
+
 		/*
 		 * for alias devices simplify error recovery and
 		 * return to upper layer
-- 
cgit v1.2.3-54-g00ecf