5 files changed, 141 insertions, 3 deletions
diff --git a/kernel/Documentation/block/biodoc.txt b/kernel/Documentation/block/biodoc.txt
index fd12c0d83..5be8a7f4c 100644
--- a/kernel/Documentation/block/biodoc.txt
+++ b/kernel/Documentation/block/biodoc.txt
@@ -1109,7 +1109,7 @@ it will loop and handle as many sectors (on a bio-segment granularity)
 as specified.
 
 Now bh->b_end_io is replaced by bio->bi_end_io, but most of the time the
-right thing to use is bio_endio(bio, uptodate) instead.
+right thing to use is bio_endio(bio) instead.
 
 If the driver is dropping the io_request_lock from its request_fn strategy,
 then it just needs to replace that with q->queue_lock instead.
diff --git a/kernel/Documentation/block/biovecs.txt b/kernel/Documentation/block/biovecs.txt
index 74a32ad52..25689584e 100644
--- a/kernel/Documentation/block/biovecs.txt
+++ b/kernel/Documentation/block/biovecs.txt
@@ -24,7 +24,7 @@ particular, presenting the illusion of partially completed biovecs so that
 normal code doesn't have to deal with bi_bvec_done.
 
  * Driver code should no longer refer to biovecs directly; we now have
-   bio_iovec() and bio_iovec_iter() macros that return literal struct biovecs,
+   bio_iovec() and bio_iter_iovec() macros that return literal struct biovecs,
    constructed from the raw biovecs but taking into account bi_bvec_done and
    bi_size.
 
@@ -109,3 +109,11 @@ Other implications:
    over all the biovecs in the new bio - which is silly as it's not needed.
 
    So, don't use bi_vcnt anymore.
+
+ * The current interface allows the block layer to split bios as needed, so we
+   could eliminate a lot of complexity particularly in stacked drivers. Code
+   that creates bios can then create whatever size bios are convenient, and
+   more importantly stacked drivers don't have to deal with both their own bio
+   size limitations and the limitations of the underlying devices. Thus
+   there's no need to define ->merge_bvec_fn() callbacks for individual block
+   drivers.
diff --git a/kernel/Documentation/block/null_blk.txt b/kernel/Documentation/block/null_blk.txt
index 2f6c6ff71..d8880ca30 100644
--- a/kernel/Documentation/block/null_blk.txt
+++ b/kernel/Documentation/block/null_blk.txt
@@ -70,3 +70,6 @@ use_per_node_hctx=[0/1]: Default: 0
      parameter.
   1: The multi-queue block layer is instantiated with a hardware dispatch
      queue for each CPU node in the system.
+
+use_lightnvm=[0/1]: Default: 0
+  Register device with LightNVM. Requires blk-mq to be used.
diff --git a/kernel/Documentation/block/pr.txt b/kernel/Documentation/block/pr.txt
new file mode 100644
index 000000000..d3eb1ca65
--- /dev/null
+++ b/kernel/Documentation/block/pr.txt
@@ -0,0 +1,119 @@
+
+Block layer support for Persistent Reservations
+===============================================
+
+The Linux kernel supports a user space interface for simplified
+Persistent Reservations which map to block devices that support
+these (like SCSI). Persistent Reservations allow restricting
+access to block devices to specific initiators in a shared storage
+setup.
+
+This document gives a general overview of the support ioctl commands.
+For a more detailed reference please refer the the SCSI Primary
+Commands standard, specifically the section on Reservations and the
+"PERSISTENT RESERVE IN" and "PERSISTENT RESERVE OUT" commands.
+
+All implementations are expected to ensure the reservations survive
+a power loss and cover all connections in a multi path environment.
+These behaviors are optional in SPC but will be automatically applied
+by Linux.
+
+
+The following types of reservations are supported:
+--------------------------------------------------
+
+ - PR_WRITE_EXCLUSIVE
+
+	Only the initiator that owns the reservation can write to the
+	device.  Any initiator can read from the device.
+
+ - PR_EXCLUSIVE_ACCESS
+
+	Only the initiator that owns the reservation can access the
+	device.
+
+ - PR_WRITE_EXCLUSIVE_REG_ONLY
+
+	Only initiators with a registered key can write to the device,
+	Any initiator can read from the device.
+
+ - PR_EXCLUSIVE_ACCESS_REG_ONLY
+
+	Only initiators with a registered key can access the device.
+
+ - PR_WRITE_EXCLUSIVE_ALL_REGS
+
+	Only initiators with a registered key can write to the device,
+	Any initiator can read from the device.
+	All initiators with a registered key are considered reservation
+	holders.
+	Please reference the SPC spec on the meaning of a reservation
+	holder if you want to use this type. 
+
+ - PR_EXCLUSIVE_ACCESS_ALL_REGS
+
+	Only initiators with a registered key can access the device.
+	All initiators with a registered key are considered reservation
+	holders.
+	Please reference the SPC spec on the meaning of a reservation
+	holder if you want to use this type. 
+
+
+The following ioctl are supported:
+----------------------------------
+
+1. IOC_PR_REGISTER
+
+This ioctl command registers a new reservation if the new_key argument
+is non-null.  If no existing reservation exists old_key must be zero,
+if an existing reservation should be replaced old_key must contain
+the old reservation key.
+
+If the new_key argument is 0 it unregisters the existing reservation passed
+in old_key.
+
+
+2. IOC_PR_RESERVE
+
+This ioctl command reserves the device and thus restricts access for other
+devices based on the type argument.  The key argument must be the existing
+reservation key for the device as acquired by the IOC_PR_REGISTER,
+IOC_PR_REGISTER_IGNORE, IOC_PR_PREEMPT or IOC_PR_PREEMPT_ABORT commands.
+
+
+3. IOC_PR_RELEASE
+
+This ioctl command releases the reservation specified by key and flags
+and thus removes any access restriction implied by it.
+
+
+4. IOC_PR_PREEMPT
+
+This ioctl command releases the existing reservation referred to by
+old_key and replaces it with a a new reservation of type for the
+reservation key new_key.
+
+
+5. IOC_PR_PREEMPT_ABORT
+
+This ioctl command works like IOC_PR_PREEMPT except that it also aborts
+any outstanding command sent over a connection identified by old_key.
+
+6. IOC_PR_CLEAR
+
+This ioctl command unregisters both key and any other reservation key
+registered with the device and drops any existing reservation.
+
+
+Flags
+-----
+
+All the ioctls have a flag field.  Currently only one flag is supported:
+
+ - PR_FL_IGNORE_KEY
+
+	Ignore the existing reservation key.  This is commonly supported for
+	IOC_PR_REGISTER, and some implementation may support the flag for
+	IOC_PR_RESERVE.
+
+For all unknown flags the kernel will return -EOPNOTSUPP.
diff --git a/kernel/Documentation/block/queue-sysfs.txt b/kernel/Documentation/block/queue-sysfs.txt
index 3a29f8914..e5d914845 100644
--- a/kernel/Documentation/block/queue-sysfs.txt
+++ b/kernel/Documentation/block/queue-sysfs.txt
@@ -20,7 +20,7 @@ This shows the size of internal allocation of the device in bytes, if
 reported by the device. A value of '0' means device does not support
 the discard functionality.
 
-discard_max_bytes (RO)
+discard_max_hw_bytes (RO)
 ----------------------
 Devices that support discard functionality may have internal limits on
 the number of bytes that can be trimmed or unmapped in a single operation.
@@ -29,6 +29,14 @@ number of bytes that can be discarded in a single operation. Discard
 requests issued to the device must not exceed this limit. A discard_max_bytes
 value of 0 means that the device does not support discard functionality.
 
+discard_max_bytes (RW)
+----------------------
+While discard_max_hw_bytes is the hardware limit for the device, this
+setting is the software limit. Some devices exhibit large latencies when
+large discards are issued, setting this value lower will make Linux issue
+smaller discards and potentially help reduce latencies induced by large
+discard operations.
+
 discard_zeroes_data (RO)
 ------------------------
 When read, this file will show if the discarded block are zeroed by the