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-rw-r--r--Documentation/nommu-mmap.txt18
1 files changed, 12 insertions, 6 deletions
diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt
index 7714f57caad5..02b89dcf38ac 100644
--- a/Documentation/nommu-mmap.txt
+++ b/Documentation/nommu-mmap.txt
@@ -109,12 +109,18 @@ and it's also much more restricted in the latter case:
109FURTHER NOTES ON NO-MMU MMAP 109FURTHER NOTES ON NO-MMU MMAP
110============================ 110============================
111 111
112 (*) A request for a private mapping of less than a page in size may not return 112 (*) A request for a private mapping of a file may return a buffer that is not
113 a page-aligned buffer. This is because the kernel calls kmalloc() to 113 page-aligned. This is because XIP may take place, and the data may not be
114 allocate the buffer, not get_free_page(). 114 paged aligned in the backing store.
115 115
116 (*) A list of all the mappings on the system is visible through /proc/maps in 116 (*) A request for an anonymous mapping will always be page aligned. If
117 no-MMU mode. 117 possible the size of the request should be a power of two otherwise some
118 of the space may be wasted as the kernel must allocate a power-of-2
119 granule but will only discard the excess if appropriately configured as
120 this has an effect on fragmentation.
121
122 (*) A list of all the private copy and anonymous mappings on the system is
123 visible through /proc/maps in no-MMU mode.
118 124
119 (*) A list of all the mappings in use by a process is visible through 125 (*) A list of all the mappings in use by a process is visible through
120 /proc/<pid>/maps in no-MMU mode. 126 /proc/<pid>/maps in no-MMU mode.