A transaction roll is not necessary immediately after setting the
INCOMPLETE flag when removing a node xattr entry with remote value
blocks. The remote block invalidation that immediately follows setting
the flag is an in-core only change. The next step after that is to start
unmapping the remote blocks from the attr fork, but the xattr remove
transaction reservation includes reservation for full tree splits of the
dabtree and bmap tree. The remote block unmap code will roll the
transaction as extents are unmapped and freed.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Some calls to xfs_trans_roll_inode and xfs_defer_finish routines are not
needed. If they are the last operations executed in these functions, and
no further changes are made, then higher level routines will roll or
commit the transactions.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
This patch adds a new helper function xfs_attr_node_shrink used to
shrink an attr name into an inode if it is small enough. This helps to
modularize the greater calling function xfs_attr_node_removename.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
This patch pulls xfs_attr_rmtval_invalidate out of
xfs_attr_rmtval_remove and into the calling functions. Eventually
__xfs_attr_rmtval_remove will replace xfs_attr_rmtval_remove when we
introduce delayed attributes. These functions are exepcted to return
-EAGAIN when they need a new transaction. Because the invalidate does
not need a new transaction, we need to separate it from the rest of the
function that does. This will enable __xfs_attr_rmtval_remove to
smoothly replace xfs_attr_rmtval_remove later.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Refactor xfs_attr_rmtval_remove to add helper function
__xfs_attr_rmtval_remove. We will use this later when we introduce
delayed attributes. This function will eventually replace
xfs_attr_rmtval_remove
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
New delayed allocation routines cannot be handling transactions so
pull them out into the calling functions
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Because new delayed attribute routines cannot roll transactions, we
carve off the parts of xfs_attr_rmtval_remove that we can use. This
will help to reduce repetitive code later when we introduce delayed
attributes.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
New delayed allocation routines cannot be handling transactions so
pull them up into the calling functions
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
To help pre-simplify xfs_attr_set_args, we need to hoist transaction
handling up, while modularizing the adjacent code down into helpers. In
this patch, hoist the commit in xfs_attr_try_sf_addname up into the
calling function, and also pull the attr list creation down.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Split out new helper function xfs_attr_leaf_try_add from
xfs_attr_leaf_addname. Because new delayed attribute routines cannot
roll transactions, we split off the parts of xfs_attr_leaf_addname that
we can use, and move the commit into the calling function.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Since delayed operations cannot roll transactions, pull up the
transaction handling into the calling function
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Break xfs_attr_rmtval_set into two helper functions
xfs_attr_rmt_find_hole and xfs_attr_rmtval_set_value.
xfs_attr_rmtval_set rolls the transaction between the helpers, but
delayed operations cannot. We will use the helpers later when
constructing new delayed attribute routines.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Delayed operations cannot return error codes. So we must check for
these conditions first before starting set or remove operations
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
This patch adds a new functions to check for the existence of an
attribute. Subroutines are also added to handle the cases of leaf
blocks, nodes or shortform. Common code that appears in existing attr
add and remove functions have been factored out to help reduce the
appearance of duplicated code. We will need these routines later for
delayed attributes since delayed operations cannot return error codes.
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix a leak-on-error bug reported by Dan Carpenter]
[darrick: fix unused variable warning reported by 0day]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reported-by: dan.carpenter@oracle.com
Reported-by: kernel test robot <lkp@intel.com>
Every call to xfs_da_state_alloc() also requires setting up state->args
and state->mp
Change xfs_da_state_alloc() to receive an xfs_da_args_t as argument and
return a xfs_da_state_t with both args and mp already set.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: reduce struct typedef usage]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
All their users have been converted to use MM API directly, no need to
keep them around anymore.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
xlog_ticket_alloc() is always called under NOFS context, except from
unmount path, which eitherway is holding many FS locks, so, there is no
need for its callers to keep passing allocation flags into it.
change xlog_ticket_alloc() to use default kmem_cache_zalloc(), remove
its alloc_flags argument, and always use GFP_NOFS | __GFP_NOFAIL flags.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Use kmem_cache_zalloc() directly.
With the exception of xlog_ticket_alloc() which will be dealt on the
next patch for readability.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Use kmem_cache_alloc() directly.
All kmem_zone_alloc() users pass 0 as flags, which are translated into:
GFP_KERNEL | __GFP_NOWARN, and kmem_zone_alloc() loops forever until the
allocation succeeds.
We can use __GFP_NOFAIL to tell the allocator to loop forever rather
than doing it ourself, and because the allocation will never fail, we do
not need to use __GFP_NOWARN anymore. Hence, all callers can be
converted to use GFP_KERNEL | __GFP_NOFAIL
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: add a comment back in about nofail]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Drop the repeated words "with" and "be" in comments.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: linux-xfs@vger.kernel.org
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The ondisk dquot stores the quota record type in the flags field.
Rename this field to d_type to make the _type relationship between the
ondisk and incore dquot more obvious.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create an XFS_DQTYPE_ANY mask for ondisk dquots flags, and use that to
ensure that we never accept any garbage flags when we're loading dquots.
While we're at it, restructure the quota type flag checking to use the
proper masking.
Note that I plan to add y2038 support soon, which will require a new
xfs_dqtype_t flag for extended timestamp support, hence all the work to
make the type masking work correctly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a new type (xfs_dqtype_t) to represent the type of an incore
dquot (user, group, project, or none). Rename the incore dquot's
dq_flags field to q_type.
This allows us to replace all the "uint type" arguments to the quota
functions with "xfs_dqtype_t type", to make it obvious when we're
passing a quota type argument into a function.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fix a few places where we open-coded this mask constant.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When XFS' quota functions take a parameter for the quota type, they only
care about the three quota record types (user, group, project).
Internal state flags and whatnot should never be passed by callers and
are an error. Now that we've moved responsibility for filtering out
internal state to the callers, we can drop the masking everywhere else.
In other words, if you call a quota function, you must only pass in
one of XFS_DQTYPE_{USER,GROUP,PROJ}.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Always use the xfs_dquot_type helper to extract the quota type from an
incore dquot. This moves responsibility for filtering internal state
information and whatnot to anybody passing around a struct xfs_dquot.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Certain functions can only act upon one quota type, so refactor those
functions to use switch statements, in keeping with all the other high
level xfs quota api calls.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Remove these macros and use xfs_dquot_type() for everything.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a small helper to test if enforcement is enabled for a
given incore dquot and replace the open-code logic testing.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We're going to split up the incore dquot state flags from the ondisk
dquot flags (eventually renaming this "type") so start by renaming the
three flags and the bitmask that are going to participate in this.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xfs_qm_reset_dqcounts (aka quotacheck) is the only xfs_dqblk_verify
caller that actually knows the specific quota type that it's looking
for. Since everything else just pass in type==0 (including the buffer
verifier), drop the parameter and open-code the check like
xfs_dquot_from_disk already does.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add all the xfs_dquot fields to the tracepoint for that type; add a new
tracepoint type for the qtrx structure (dquot transaction deltas); and
use our new tracepoints. This makes it easier for the author to trace
changes to dquot counters for debugging.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently, xfs quotas have the ability to send netlink warnings when a
user exceeds the limits. They also have all the support code necessary
to convert softlimit warnings into failures if the number of warnings
exceeds a limit set by the administrator. Unfortunately, we never
actually increase the warning counter, so this never actually happens.
Make it so we actually do something useful with the warning counts.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
We always initialize the default quota limits to something nowadays, so
we don't need to check that the defaults are set to something before
using them.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Hoist the code that adjusts the incore quota reservation count
adjustments into a separate function, both to reduce the level of
indentation and also to reduce the amount of open-coded logic.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we've refactored the resource usage and limits into
per-resource structures, we can refactor some of the open-coded
reservation limit checking in xfs_trans_dqresv.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we can pass around quota resource and limit structures, clean
up the open-coded field setting in xfs_qm_scall_setqlim.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Refactor the open-coded test for whether or not we're over quota.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
struct xfs_dquot already has a pointer to the xfs mount, so remove the
redundant parameter from xfs_qm_adjust_dq*.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we've split up the dquot resource fields into separate structs,
do the same for the default limits to enable further refactoring.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we've stopped using qcore entirely, drop it from the incore
dquot.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add timers fields to the incore dquot, and use that instead of the ones
in qcore. This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Add warning counter fields to the incore dquot, and use that instead of
the ones in qcore. This eliminates a bunch of endian conversions and
will eventually allow us to remove qcore entirely.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Add counter fields to the incore dquot, and use that instead of the ones
in qcore. This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Add limits fields in the incore dquot, and use that instead of the ones
in qcore. This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Introduce a new struct xfs_dquot_res that we'll use to track all the
incore data for a particular resource type (block, inode, rt block).
This will help us (once we've eliminated q_core) to declutter quota
functions that currently open-code field access or pass around fields
around explicitly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Add a dquot id field to the incore dquot, and use that instead of the
one in qcore. This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.
We also rearrange the start of xfs_dquot to remove padding holes, saving
8 bytes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Use the incore dq_flags to figure out the dquot type. This is the first
step towards removing xfs_disk_dquot from the incore dquot.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Move the dquot cluster size #define to xfs_format.h. It is an important
part of the ondisk format because the ondisk dquot record size is not an
even power of two, which means that the buffer size we use is
significant here because the kernel leaves slack space at the end of the
buffer to avoid having to deal with a dquot record crossing a block
boundary.
This is also an excuse to fix one of the longstanding discrepancies
between kernel and userspace libxfs headers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Rename the existing incore dquot "dq_flags" field to "q_flags" to match
everything else in the structure, then move the two actual dquot state
flags to the XFS_DQFLAG_ namespace from XFS_DQ_.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
