The problem described in 2a5d574 also applies to XFS's file or inode
fallocate method. Both paths may trigger writeback and expose this
issue, see the full stack below.
When layered on XFS a warning will be emitted under CentOS7 when entering
either the file or inode fallocate method with PF_FSTRANS already set.
To avoid triggering this error PF_FSTRANS is cleared and then reset
in vn_space().
WARNING: at fs/xfs/xfs_aops.c:982 xfs_vm_writepage+0x58b/0x5d0
Linux 4.11 compat: remove stub for __put_task_struct
Before kernel 2.6.29 credentials were embedded in task_structs, and zfs had
cases where one thread would need to refer to the credential of another thread,
forcing it to take a hold on the foreign thread's task_struct to ensure it was
not freed.
Since 2.6.29, the credential has been moved out of the task_struct into a
cred_t.
In addition, the mainline kernel originally did not export __put_task_struct()
but the RHEL5 kernel did, according to zfsonlinux/spl@e811949a570. As of
2.6.39 the mainline kernel exports it.
There is no longer zfs code that takes or releases holds on a task_struct, and
so there is no longer any reference to __put_task_struct().
This affects the linux 4.11 kernel because the prototype for
__put_task_struct() is in a new include file (linux/sched/task.h) and so the
config check failed to detect the exported symbol.
Removing the unnecessary stub and corresponding config check. This works on
kernels since the oldest one currently supported, 2.6.32 as shipped with
Centos/RHEL.
Reviewed-by: Chunwei Chen <email address hidden>
Reviewed-by: Brian Behlendorf <email address hidden>
Signed-off-by: Olaf Faaland <email address hidden>
Closes #608
There are changes to vfs_getattr() in torvalds/linux@a528d35. The new
interface is:
int vfs_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
The request_mask argument indicates which field(s) the caller intends to
use. Fields the caller does not specify via request_mask may be set in
the returned struct anyway, but their values may be approximate.
The query_flags argument indicates whether the filesystem must update
the attributes from the backing store.
This patch uses the query_flags which result in vfs_getattr behaving the same
as it did with the 2-argument version which the kernel provided before
Linux 4.11.
Members blksize and blocks are now always the same size regardless of
arch. They match the size of the equivalent members in vnode_t.
The configure checks are modified to ensure that the appropriate
vfs_getattr() interface is used.
A more complete fix, removing the ZFS dependency on vfs_getattr()
entirely, is deferred as it is a much larger project.
Reviewed-by: Chunwei Chen <email address hidden>
Reviewed-by: Brian Behlendorf <email address hidden>
Signed-off-by: Olaf Faaland <email address hidden>
Closes #608
Unlike other architectures which sanitize the LDFLAGS from the
environment in arch/<arch>/Makefile. The powerpc Makefile
allows LDFLAGS to be passed through resulting in the following
build failure.
/usr/bin/ld: unrecognized option '-Wl,-z,relro'
LDFLAGS is set in /usr/lib/rpm/redhat/macros by default. Clear
the environment variable when building kmods for powerpc.
Reviewed-by: Giuseppe Di Natale <email address hidden>
Signed-off-by: Brian Behlendorf <email address hidden>
Closes #607
