diff options
Diffstat (limited to 'Documentation/block/biodoc.txt')
| -rw-r--r-- | Documentation/block/biodoc.txt | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt index 34bf8f6..980a6e6 100644 --- a/Documentation/block/biodoc.txt +++ b/Documentation/block/biodoc.txt @@ -391,7 +391,7 @@ forced such requests to be broken up into small chunks before being passed on to the generic block layer, only to be merged by the i/o scheduler when the underlying device was capable of handling the i/o in one shot. Also, using the buffer head as an i/o structure for i/os that didn't originate -from the buffer cache unecessarily added to the weight of the descriptors +from the buffer cache unnecessarily added to the weight of the descriptors which were generated for each such chunk. The following were some of the goals and expectations considered in the @@ -403,14 +403,14 @@ i. Should be appropriate as a descriptor for both raw and buffered i/o - for raw i/o. ii. Ability to represent high-memory buffers (which do not have a virtual address mapping in kernel address space). -iii.Ability to represent large i/os w/o unecessarily breaking them up (i.e +iii.Ability to represent large i/os w/o unnecessarily breaking them up (i.e greater than PAGE_SIZE chunks in one shot) iv. At the same time, ability to retain independent identity of i/os from different sources or i/o units requiring individual completion (e.g. for latency reasons) v. Ability to represent an i/o involving multiple physical memory segments (including non-page aligned page fragments, as specified via readv/writev) - without unecessarily breaking it up, if the underlying device is capable of + without unnecessarily breaking it up, if the underlying device is capable of handling it. vi. Preferably should be based on a memory descriptor structure that can be passed around different types of subsystems or layers, maybe even |
