diff options
| author | Michel Lespinasse <walken@google.com> | 2013-02-22 16:32:37 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-23 17:50:10 -0800 |
| commit | bebeb3d68b24bb4132d452c5707fe321208bcbcd (patch) | |
| tree | 6e609cb7323fb1b4b7026fa0e35867145a181094 /mm/nommu.c | |
| parent | 940e7da5163029978c2f6b5bbe213607add59062 (diff) | |
| download | lwn-bebeb3d68b24bb4132d452c5707fe321208bcbcd.tar.gz lwn-bebeb3d68b24bb4132d452c5707fe321208bcbcd.zip | |
mm: introduce mm_populate() for populating new vmas
When creating new mappings using the MAP_POPULATE / MAP_LOCKED flags (or
with MCL_FUTURE in effect), we want to populate the pages within the
newly created vmas. This may take a while as we may have to read pages
from disk, so ideally we want to do this outside of the write-locked
mmap_sem region.
This change introduces mm_populate(), which is used to defer populating
such mappings until after the mmap_sem write lock has been released.
This is implemented as a generalization of the former do_mlock_pages(),
which accomplished the same task but was using during mlock() /
mlockall().
Signed-off-by: Michel Lespinasse <walken@google.com>
Reported-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Andy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/nommu.c')
| -rw-r--r-- | mm/nommu.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/mm/nommu.c b/mm/nommu.c index b20db4e22263..7296a5a280e7 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1250,7 +1250,8 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long len, unsigned long prot, unsigned long flags, - unsigned long pgoff) + unsigned long pgoff, + bool *populate) { struct vm_area_struct *vma; struct vm_region *region; @@ -1260,6 +1261,8 @@ unsigned long do_mmap_pgoff(struct file *file, kenter(",%lx,%lx,%lx,%lx,%lx", addr, len, prot, flags, pgoff); + *populate = false; + /* decide whether we should attempt the mapping, and if so what sort of * mapping */ ret = validate_mmap_request(file, addr, len, prot, flags, pgoff, |