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-rw-r--r--Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads5
-rw-r--r--Documentation/block/biodoc.txt11
-rw-r--r--Documentation/block/null_blk.txt19
3 files changed, 19 insertions, 16 deletions
diff --git a/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads b/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads
deleted file mode 100644
index b0b0eeb20fe3..000000000000
--- a/Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads
+++ /dev/null
@@ -1,5 +0,0 @@
-What: /proc/sys/vm/nr_pdflush_threads
-Date: June 2012
-Contact: Wanpeng Li <liwp@linux.vnet.ibm.com>
-Description: Since pdflush is replaced by per-BDI flusher, the interface of old pdflush
- exported in /proc/sys/vm/ should be removed.
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 9490f2845f06..86927029a52d 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -216,10 +216,9 @@ may need to abort DMA operations and revert to PIO for the transfer, in
which case a virtual mapping of the page is required. For SCSI it is also
done in some scenarios where the low level driver cannot be trusted to
handle a single sg entry correctly. The driver is expected to perform the
-kmaps as needed on such occasions using the __bio_kmap_atomic and bio_kmap_irq
-routines as appropriate. A driver could also use the blk_queue_bounce()
-routine on its own to bounce highmem i/o to low memory for specific requests
-if so desired.
+kmaps as needed on such occasions as appropriate. A driver could also use
+the blk_queue_bounce() routine on its own to bounce highmem i/o to low
+memory for specific requests if so desired.
iii. The i/o scheduler algorithm itself can be replaced/set as appropriate
@@ -1137,8 +1136,8 @@ use dma_map_sg for scatter gather) to be able to ship it to the driver. For
PIO drivers (or drivers that need to revert to PIO transfer once in a
while (IDE for example)), where the CPU is doing the actual data
transfer a virtual mapping is needed. If the driver supports highmem I/O,
-(Sec 1.1, (ii) ) it needs to use __bio_kmap_atomic and bio_kmap_irq to
-temporarily map a bio into the virtual address space.
+(Sec 1.1, (ii) ) it needs to use kmap_atomic or similar to temporarily map
+a bio into the virtual address space.
8. Prior/Related/Impacted patches
diff --git a/Documentation/block/null_blk.txt b/Documentation/block/null_blk.txt
index 3140dbd860d8..733927a7b501 100644
--- a/Documentation/block/null_blk.txt
+++ b/Documentation/block/null_blk.txt
@@ -38,7 +38,7 @@ gb=[Size in GB]: Default: 250GB
bs=[Block size (in bytes)]: Default: 512 bytes
The block size reported to the system.
-nr_devices=[Number of devices]: Default: 2
+nr_devices=[Number of devices]: Default: 1
Number of block devices instantiated. They are instantiated as /dev/nullb0,
etc.
@@ -52,13 +52,13 @@ irqmode=[0-2]: Default: 1-Soft-irq
2: Timer: Waits a specific period (completion_nsec) for each IO before
completion.
-completion_nsec=[ns]: Default: 10.000ns
+completion_nsec=[ns]: Default: 10,000ns
Combined with irqmode=2 (timer). The time each completion event must wait.
-submit_queues=[0..nr_cpus]:
+submit_queues=[1..nr_cpus]:
The number of submission queues attached to the device driver. If unset, it
- defaults to 1 on single-queue and bio-based instances. For multi-queue,
- it is ignored when use_per_node_hctx module parameter is 1.
+ defaults to 1. For multi-queue, it is ignored when use_per_node_hctx module
+ parameter is 1.
hw_queue_depth=[0..qdepth]: Default: 64
The hardware queue depth of the device.
@@ -73,3 +73,12 @@ use_per_node_hctx=[0/1]: Default: 0
use_lightnvm=[0/1]: Default: 0
Register device with LightNVM. Requires blk-mq and CONFIG_NVM to be enabled.
+
+no_sched=[0/1]: Default: 0
+ 0: nullb* use default blk-mq io scheduler.
+ 1: nullb* doesn't use io scheduler.
+
+shared_tags=[0/1]: Default: 0
+ 0: Tag set is not shared.
+ 1: Tag set shared between devices for blk-mq. Only makes sense with
+ nr_devices > 1, otherwise there's no tag set to share.