diff options
Diffstat (limited to 'Documentation/block/biodoc.txt')
-rw-r--r-- | Documentation/block/biodoc.txt | 11 |
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 | |||
186 | do not have a corresponding kernel virtual address space mapping) and | 186 | do not have a corresponding kernel virtual address space mapping) and |
187 | low-memory pages. | 187 | low-memory pages. |
188 | 188 | ||
189 | Note: Please refer to DMA-mapping.txt for a discussion on PCI high mem DMA | 189 | Note: Please refer to Documentation/PCI/PCI-DMA-mapping.txt for a discussion |
190 | aspects and mapping of scatter gather lists, and support for 64 bit PCI. | 190 | on PCI high mem DMA aspects and mapping of scatter gather lists, and support |
191 | for 64 bit PCI. | ||
191 | 192 | ||
192 | Special handling is required only for cases where i/o needs to happen on | 193 | Special handling is required only for cases where i/o needs to happen on |
193 | pages at physical memory addresses beyond what the device can support. In these | 194 | pages 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 | ||
956 | elevator_dispatch_fn fills the dispatch queue with ready requests. | 957 | elevator_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 | ||
963 | elevator_add_req_fn called to add a new request into the scheduler | 964 | elevator_add_req_fn* called to add a new request into the scheduler |
964 | 965 | ||
965 | elevator_queue_empty_fn returns true if the merge queue is empty. | 966 | elevator_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. | |||
990 | elevator_deactivate_req_fn Called when device driver decides to delay | 991 | elevator_deactivate_req_fn Called when device driver decides to delay |
991 | a request by requeueing it. | 992 | a request by requeueing it. |
992 | 993 | ||
993 | elevator_init_fn | 994 | elevator_init_fn* |
994 | elevator_exit_fn Allocate and free any elevator specific storage | 995 | elevator_exit_fn Allocate and free any elevator specific storage |
995 | for a queue. | 996 | for a queue. |
996 | 997 | ||