Commit ed5e5894 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

nommu: fix SYSV SHM for NOMMU 



Commit c4caa778 ("file
->get_unmapped_area() shouldn't duplicate work of get_unmapped_area()")
broke SYSV SHM for NOMMU by taking away the pointer to
shm_get_unmapped_area() from shm_file_operations.

Put it back conditionally on CONFIG_MMU=n.

file->f_ops->get_unmapped_area() is used to find out the base address for a
mapping of a mappable chardev device or mappable memory-based file (such as a
ramfs file).  It needs to be called prior to file->f_ops->mmap() being called.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Cc: Greg Ungerer <gerg@snapgear.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8ff410da

ipc/shm.c

+3 −0
Original line number Diff line number Diff line
@@ -298,6 +298,9 @@ static const struct file_operations shm_file_operations = { 
	.mmap		= shm_mmap,

	.fsync		= shm_fsync,

	.release	= shm_release,

#ifndef CONFIG_MMU

	.get_unmapped_area	= shm_get_unmapped_area,

#endif

};



static const struct file_operations shm_file_operations_huge = {

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