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-rw-r--r--Documentation/block/biodoc.txt11
1 files changed, 6 insertions, 5 deletions
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 3c5434c83daf..ecad6ee75705 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -186,8 +186,9 @@ a virtual address mapping (unlike the earlier scheme of virtual address
186do not have a corresponding kernel virtual address space mapping) and 186do not have a corresponding kernel virtual address space mapping) and
187low-memory pages. 187low-memory pages.
188 188
189Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA 189Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion
190aspects and mapping of scatter gather lists, and support for 64 bit PCI. 190on PCI high mem DMA aspects and mapping of scatter gather lists, and support
191for 64 bit PCI.
191 192
192Special handling is required only for cases where i/o needs to happen on 193Special handling is required only for cases where i/o needs to happen on
193pages at physical memory addresses beyond what the device can support. In these 194pages at physical memory addresses beyond what the device can support. In these
@@ -953,14 +954,14 @@ elevator_allow_merge_fn called whenever the block layer determines
953 results in some sort of conflict internally, 954 results in some sort of conflict internally,
954 this hook allows it to do that. 955 this hook allows it to do that.
955 956
956elevator_dispatch_fn fills the dispatch queue with ready requests. 957elevator_dispatch_fn* fills the dispatch queue with ready requests.
957 I/O schedulers are free to postpone requests by 958 I/O schedulers are free to postpone requests by
958 not filling the dispatch queue unless @force 959 not filling the dispatch queue unless @force
959 is non-zero. Once dispatched, I/O schedulers 960 is non-zero. Once dispatched, I/O schedulers
960 are not allowed to manipulate the requests - 961 are not allowed to manipulate the requests -
961 they belong to generic dispatch queue. 962 they belong to generic dispatch queue.
962 963
963elevator_add_req_fn called to add a new request into the scheduler 964elevator_add_req_fn* called to add a new request into the scheduler
964 965
965elevator_queue_empty_fn returns true if the merge queue is empty. 966elevator_queue_empty_fn returns true if the merge queue is empty.
966 Drivers shouldn't use this, but rather check 967 Drivers shouldn't use this, but rather check
@@ -990,7 +991,7 @@ elevator_activate_req_fn Called when device driver first sees a request.
990elevator_deactivate_req_fn Called when device driver decides to delay 991elevator_deactivate_req_fn Called when device driver decides to delay
991 a request by requeueing it. 992 a request by requeueing it.
992 993
993elevator_init_fn 994elevator_init_fn*
994elevator_exit_fn Allocate and free any elevator specific storage 995elevator_exit_fn Allocate and free any elevator specific storage
995 for a queue. 996 for a queue.
996 997