diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/obsolete/proc-sys-vm-nr_pdflush_threads | 5 | ||||
| -rw-r--r-- | Documentation/block/biodoc.txt | 11 | ||||
| -rw-r--r-- | Documentation/block/null_blk.txt | 19 |
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. |