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-rw-r--r--Documentation/block/biodoc.txt6
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index 34bf8f60d8f8..980a6e6f5981 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
391on to the generic block layer, only to be merged by the i/o scheduler 391on to the generic block layer, only to be merged by the i/o scheduler
392when the underlying device was capable of handling the i/o in one shot. 392when the underlying device was capable of handling the i/o in one shot.
393Also, using the buffer head as an i/o structure for i/os that didn't originate 393Also, using the buffer head as an i/o structure for i/os that didn't originate
394from the buffer cache unecessarily added to the weight of the descriptors 394from the buffer cache unnecessarily added to the weight of the descriptors
395which were generated for each such chunk. 395which were generated for each such chunk.
396 396
397The following were some of the goals and expectations considered in the 397The 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 -
403 for raw i/o. 403 for raw i/o.
404ii. Ability to represent high-memory buffers (which do not have a virtual 404ii. Ability to represent high-memory buffers (which do not have a virtual
405 address mapping in kernel address space). 405 address mapping in kernel address space).
406iii.Ability to represent large i/os w/o unecessarily breaking them up (i.e 406iii.Ability to represent large i/os w/o unnecessarily breaking them up (i.e
407 greater than PAGE_SIZE chunks in one shot) 407 greater than PAGE_SIZE chunks in one shot)
408iv. At the same time, ability to retain independent identity of i/os from 408iv. At the same time, ability to retain independent identity of i/os from
409 different sources or i/o units requiring individual completion (e.g. for 409 different sources or i/o units requiring individual completion (e.g. for
410 latency reasons) 410 latency reasons)
411v. Ability to represent an i/o involving multiple physical memory segments 411v. Ability to represent an i/o involving multiple physical memory segments
412 (including non-page aligned page fragments, as specified via readv/writev) 412 (including non-page aligned page fragments, as specified via readv/writev)
413 without unecessarily breaking it up, if the underlying device is capable of 413 without unnecessarily breaking it up, if the underlying device is capable of
414 handling it. 414 handling it.
415vi. Preferably should be based on a memory descriptor structure that can be 415vi. Preferably should be based on a memory descriptor structure that can be
416 passed around different types of subsystems or layers, maybe even 416 passed around different types of subsystems or layers, maybe even