diff options
| author | Hugh Dickins <hugh@veritas.com> | 2005-01-07 21:58:02 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@evo.osdl.org> | 2005-01-07 21:58:02 -0800 |
| commit | b37e39b03bcd49397cac7b937d9b180157705e08 (patch) | |
| tree | bff70e85ba5286bb0c150b260eb1ace00242a6da /include/linux | |
| parent | de146a08f93f5c4ab71503a79a7c5e300065b39a (diff) | |
[PATCH] vmtrunc: truncate_count not atomic
Why is mapping->truncate_count atomic? It's incremented inside i_mmap_lock
(and i_sem), and the reads don't need it to be atomic.
And why smp_rmb() before call to ->nopage? The compiler cannot reorder the
initial assignment of sequence after the call to ->nopage, and no cpu (yet!)
can read from the future, which is all that matters there.
And delete totally bogus reset of truncate_count from blkmtd add_device.
truncate_count is all about detecting i_size changes: i_size does not change
there; and if it did, the count should be incremented not reset.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/fs.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h index 2d9885aa2626..cd0b31b4afba 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -341,7 +341,7 @@ struct address_space { struct prio_tree_root i_mmap; /* tree of private and shared mappings */ struct list_head i_mmap_nonlinear;/*list VM_NONLINEAR mappings */ spinlock_t i_mmap_lock; /* protect tree, count, list */ - atomic_t truncate_count; /* Cover race condition with truncate */ + unsigned int truncate_count; /* Cover race condition with truncate */ unsigned long nrpages; /* number of total pages */ pgoff_t writeback_index;/* writeback starts here */ struct address_space_operations *a_ops; /* methods */ |