diff options
| author |   José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-11 10:41:07 +0300 |
|---|---|---|
| committer | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-13 08:17:18 +0300 |
| commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
| tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/Documentation/filesystems/dax.txt | |
| parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) | |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/Documentation/filesystems/dax.txt')
| -rw-r--r-- | kernel/Documentation/filesystems/dax.txt | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/kernel/Documentation/filesystems/dax.txt b/kernel/Documentation/filesystems/dax.txt index baf411186..7bde64014 100644 --- a/kernel/Documentation/filesystems/dax.txt +++ b/kernel/Documentation/filesystems/dax.txt @@ -18,8 +18,10 @@ Usage ----- If you have a block device which supports DAX, you can make a filesystem -on it as usual. When mounting it, use the -o dax option manually -or add 'dax' to the options in /etc/fstab. +on it as usual. The DAX code currently only supports files with a block +size equal to your kernel's PAGE_SIZE, so you may need to specify a block +size when creating the filesystem. When mounting it, use the "-o dax" +option on the command line or add 'dax' to the options in /etc/fstab. Implementation Tips for Block Driver Writers @@ -58,9 +60,10 @@ Filesystem support consists of - implementing the direct_IO address space operation, and calling dax_do_io() instead of blockdev_direct_IO() if S_DAX is set - implementing an mmap file operation for DAX files which sets the - VM_MIXEDMAP flag on the VMA, and setting the vm_ops to include handlers - for fault and page_mkwrite (which should probably call dax_fault() and - dax_mkwrite(), passing the appropriate get_block() callback) + VM_MIXEDMAP and VM_HUGEPAGE flags on the VMA, and setting the vm_ops to + include handlers for fault, pmd_fault and page_mkwrite (which should + probably call dax_fault(), dax_pmd_fault() and dax_mkwrite(), passing the + appropriate get_block() callback) - calling dax_truncate_page() instead of block_truncate_page() for DAX files - calling dax_zero_page_range() instead of zero_user() for DAX files - ensuring that there is sufficient locking between reads, writes, |