afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
|
|
|
/* Fileserver-directed operation handling.
|
|
|
|
|
*
|
|
|
|
|
* Copyright (C) 2020 Red Hat, Inc. All Rights Reserved.
|
|
|
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
|
#include <linux/slab.h>
|
|
|
|
|
#include <linux/fs.h>
|
|
|
|
|
#include "internal.h"
|
|
|
|
|
|
|
|
|
|
static atomic_t afs_operation_debug_counter;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Create an operation against a volume.
|
|
|
|
|
*/
|
|
|
|
|
struct afs_operation *afs_alloc_operation(struct key *key, struct afs_volume *volume)
|
|
|
|
|
{
|
|
|
|
|
struct afs_operation *op;
|
|
|
|
|
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
op = kzalloc(sizeof(*op), GFP_KERNEL);
|
|
|
|
|
if (!op)
|
|
|
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
|
|
|
|
|
|
if (!key) {
|
|
|
|
|
key = afs_request_key(volume->cell);
|
|
|
|
|
if (IS_ERR(key)) {
|
|
|
|
|
kfree(op);
|
|
|
|
|
return ERR_CAST(key);
|
|
|
|
|
}
|
|
|
|
|
} else {
|
|
|
|
|
key_get(key);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
op->key = key;
|
2020-04-30 00:02:04 +08:00
|
|
|
op->volume = afs_get_volume(volume, afs_volume_trace_get_new_op);
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
op->net = volume->cell->net;
|
|
|
|
|
op->cb_v_break = volume->cb_v_break;
|
|
|
|
|
op->debug_id = atomic_inc_return(&afs_operation_debug_counter);
|
|
|
|
|
op->error = -EDESTADDRREQ;
|
|
|
|
|
op->ac.error = SHRT_MAX;
|
|
|
|
|
|
|
|
|
|
_leave(" = [op=%08x]", op->debug_id);
|
|
|
|
|
return op;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Lock the vnode(s) being operated upon.
|
|
|
|
|
*/
|
|
|
|
|
static bool afs_get_io_locks(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
struct afs_vnode *vnode = op->file[0].vnode;
|
|
|
|
|
struct afs_vnode *vnode2 = op->file[1].vnode;
|
|
|
|
|
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
if (op->flags & AFS_OPERATION_UNINTR) {
|
|
|
|
|
mutex_lock(&vnode->io_lock);
|
|
|
|
|
op->flags |= AFS_OPERATION_LOCK_0;
|
|
|
|
|
_leave(" = t [1]");
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (!vnode2 || !op->file[1].need_io_lock || vnode == vnode2)
|
|
|
|
|
vnode2 = NULL;
|
|
|
|
|
|
|
|
|
|
if (vnode2 > vnode)
|
|
|
|
|
swap(vnode, vnode2);
|
|
|
|
|
|
|
|
|
|
if (mutex_lock_interruptible(&vnode->io_lock) < 0) {
|
2020-07-08 16:27:07 +08:00
|
|
|
op->error = -ERESTARTSYS;
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
op->flags |= AFS_OPERATION_STOP;
|
|
|
|
|
_leave(" = f [I 0]");
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
op->flags |= AFS_OPERATION_LOCK_0;
|
|
|
|
|
|
|
|
|
|
if (vnode2) {
|
|
|
|
|
if (mutex_lock_interruptible_nested(&vnode2->io_lock, 1) < 0) {
|
2020-07-08 16:27:07 +08:00
|
|
|
op->error = -ERESTARTSYS;
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
op->flags |= AFS_OPERATION_STOP;
|
|
|
|
|
mutex_unlock(&vnode->io_lock);
|
|
|
|
|
op->flags &= ~AFS_OPERATION_LOCK_0;
|
|
|
|
|
_leave(" = f [I 1]");
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
op->flags |= AFS_OPERATION_LOCK_1;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
_leave(" = t [2]");
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void afs_drop_io_locks(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
struct afs_vnode *vnode = op->file[0].vnode;
|
|
|
|
|
struct afs_vnode *vnode2 = op->file[1].vnode;
|
|
|
|
|
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
if (op->flags & AFS_OPERATION_LOCK_1)
|
|
|
|
|
mutex_unlock(&vnode2->io_lock);
|
|
|
|
|
if (op->flags & AFS_OPERATION_LOCK_0)
|
|
|
|
|
mutex_unlock(&vnode->io_lock);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void afs_prepare_vnode(struct afs_operation *op, struct afs_vnode_param *vp,
|
|
|
|
|
unsigned int index)
|
|
|
|
|
{
|
|
|
|
|
struct afs_vnode *vnode = vp->vnode;
|
|
|
|
|
|
|
|
|
|
if (vnode) {
|
|
|
|
|
vp->fid = vnode->fid;
|
|
|
|
|
vp->dv_before = vnode->status.data_version;
|
|
|
|
|
vp->cb_break_before = afs_calc_vnode_cb_break(vnode);
|
|
|
|
|
if (vnode->lock_state != AFS_VNODE_LOCK_NONE)
|
|
|
|
|
op->flags |= AFS_OPERATION_CUR_ONLY;
|
afs: Fix speculative status fetches
The generic/464 xfstest causes kAFS to emit occasional warnings of the
form:
kAFS: vnode modified {100055:8a} 30->31 YFS.StoreData64 (c=6015)
This indicates that the data version received back from the server did not
match the expected value (the DV should be incremented monotonically for
each individual modification op committed to a vnode).
What is happening is that a lookup call is doing a bulk status fetch
speculatively on a bunch of vnodes in a directory besides getting the
status of the vnode it's actually interested in. This is racing with a
StoreData operation (though it could also occur with, say, a MakeDir op).
On the client, a modification operation locks the vnode, but the bulk
status fetch only locks the parent directory, so no ordering is imposed
there (thereby avoiding an avenue to deadlock).
On the server, the StoreData op handler doesn't lock the vnode until it's
received all the request data, and downgrades the lock after committing the
data until it has finished sending change notifications to other clients -
which allows the status fetch to occur before it has finished.
This means that:
- a status fetch can access the target vnode either side of the exclusive
section of the modification
- the status fetch could start before the modification, yet finish after,
and vice-versa.
- the status fetch and the modification RPCs can complete in either order.
- the status fetch can return either the before or the after DV from the
modification.
- the status fetch might regress the locally cached DV.
Some of these are handled by the previous fix[1], but that's not sufficient
because it checks the DV it received against the DV it cached at the start
of the op, but the DV might've been updated in the meantime by a locally
generated modification op.
Fix this by the following means:
(1) Keep track of when we're performing a modification operation on a
vnode. This is done by marking vnode parameters with a 'modification'
note that causes the AFS_VNODE_MODIFYING flag to be set on the vnode
for the duration.
(2) Alter the speculation race detection to ignore speculative status
fetches if either the vnode is marked as being modified or the data
version number is not what we expected.
Note that whilst the "vnode modified" warning does get recovered from as it
causes the client to refetch the status at the next opportunity, it will
also invalidate the pagecache, so changes might get lost.
Fixes: a9e5c87ca744 ("afs: Fix speculative status fetch going out of order wrt to modifications")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-and-reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/160605082531.252452.14708077925602709042.stgit@warthog.procyon.org.uk/ [1]
Link: https://lore.kernel.org/linux-fsdevel/161961335926.39335.2552653972195467566.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 20:47:08 +08:00
|
|
|
if (vp->modification)
|
|
|
|
|
set_bit(AFS_VNODE_MODIFYING, &vnode->flags);
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (vp->fid.vnode)
|
|
|
|
|
_debug("PREP[%u] {%llx:%llu.%u}",
|
|
|
|
|
index, vp->fid.vid, vp->fid.vnode, vp->fid.unique);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Begin an operation on the fileserver.
|
|
|
|
|
*
|
|
|
|
|
* Fileserver operations are serialised on the server by vnode, so we serialise
|
|
|
|
|
* them here also using the io_lock.
|
|
|
|
|
*/
|
|
|
|
|
bool afs_begin_vnode_operation(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
struct afs_vnode *vnode = op->file[0].vnode;
|
|
|
|
|
|
|
|
|
|
ASSERT(vnode);
|
|
|
|
|
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
if (op->file[0].need_io_lock)
|
|
|
|
|
if (!afs_get_io_locks(op))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
afs_prepare_vnode(op, &op->file[0], 0);
|
|
|
|
|
afs_prepare_vnode(op, &op->file[1], 1);
|
|
|
|
|
op->cb_v_break = op->volume->cb_v_break;
|
|
|
|
|
_leave(" = true");
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Tidy up a filesystem cursor and unlock the vnode.
|
|
|
|
|
*/
|
|
|
|
|
static void afs_end_vnode_operation(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
if (op->error == -EDESTADDRREQ ||
|
|
|
|
|
op->error == -EADDRNOTAVAIL ||
|
|
|
|
|
op->error == -ENETUNREACH ||
|
|
|
|
|
op->error == -EHOSTUNREACH)
|
|
|
|
|
afs_dump_edestaddrreq(op);
|
|
|
|
|
|
|
|
|
|
afs_drop_io_locks(op);
|
|
|
|
|
|
|
|
|
|
if (op->error == -ECONNABORTED)
|
|
|
|
|
op->error = afs_abort_to_error(op->ac.abort_code);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Wait for an in-progress operation to complete.
|
|
|
|
|
*/
|
|
|
|
|
void afs_wait_for_operation(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
_enter("");
|
|
|
|
|
|
|
|
|
|
while (afs_select_fileserver(op)) {
|
2020-04-30 08:03:49 +08:00
|
|
|
op->cb_s_break = op->server->cb_s_break;
|
|
|
|
|
if (test_bit(AFS_SERVER_FL_IS_YFS, &op->server->flags) &&
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
op->ops->issue_yfs_rpc)
|
|
|
|
|
op->ops->issue_yfs_rpc(op);
|
2021-03-02 18:26:45 +08:00
|
|
|
else if (op->ops->issue_afs_rpc)
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
op->ops->issue_afs_rpc(op);
|
2021-03-02 18:26:45 +08:00
|
|
|
else
|
|
|
|
|
op->ac.error = -ENOTSUPP;
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
|
2021-03-02 18:26:45 +08:00
|
|
|
if (op->call)
|
|
|
|
|
op->error = afs_wait_for_call_to_complete(op->call, &op->ac);
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
}
|
|
|
|
|
|
2020-06-16 07:34:09 +08:00
|
|
|
switch (op->error) {
|
|
|
|
|
case 0:
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
_debug("success");
|
|
|
|
|
op->ops->success(op);
|
2020-06-16 07:34:09 +08:00
|
|
|
break;
|
|
|
|
|
case -ECONNABORTED:
|
|
|
|
|
if (op->ops->aborted)
|
|
|
|
|
op->ops->aborted(op);
|
2020-09-18 16:11:15 +08:00
|
|
|
fallthrough;
|
2020-06-16 07:34:09 +08:00
|
|
|
default:
|
2020-09-18 16:11:15 +08:00
|
|
|
if (op->ops->failed)
|
|
|
|
|
op->ops->failed(op);
|
2020-06-16 07:34:09 +08:00
|
|
|
break;
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
|
|
afs_end_vnode_operation(op);
|
|
|
|
|
|
|
|
|
|
if (op->error == 0 && op->ops->edit_dir) {
|
|
|
|
|
_debug("edit_dir");
|
|
|
|
|
op->ops->edit_dir(op);
|
|
|
|
|
}
|
|
|
|
|
_leave("");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Dispose of an operation.
|
|
|
|
|
*/
|
|
|
|
|
int afs_put_operation(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
int i, ret = op->error;
|
|
|
|
|
|
|
|
|
|
_enter("op=%08x,%d", op->debug_id, ret);
|
|
|
|
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|
|
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|
|
if (op->ops && op->ops->put)
|
|
|
|
|
op->ops->put(op);
|
afs: Fix speculative status fetches
The generic/464 xfstest causes kAFS to emit occasional warnings of the
form:
kAFS: vnode modified {100055:8a} 30->31 YFS.StoreData64 (c=6015)
This indicates that the data version received back from the server did not
match the expected value (the DV should be incremented monotonically for
each individual modification op committed to a vnode).
What is happening is that a lookup call is doing a bulk status fetch
speculatively on a bunch of vnodes in a directory besides getting the
status of the vnode it's actually interested in. This is racing with a
StoreData operation (though it could also occur with, say, a MakeDir op).
On the client, a modification operation locks the vnode, but the bulk
status fetch only locks the parent directory, so no ordering is imposed
there (thereby avoiding an avenue to deadlock).
On the server, the StoreData op handler doesn't lock the vnode until it's
received all the request data, and downgrades the lock after committing the
data until it has finished sending change notifications to other clients -
which allows the status fetch to occur before it has finished.
This means that:
- a status fetch can access the target vnode either side of the exclusive
section of the modification
- the status fetch could start before the modification, yet finish after,
and vice-versa.
- the status fetch and the modification RPCs can complete in either order.
- the status fetch can return either the before or the after DV from the
modification.
- the status fetch might regress the locally cached DV.
Some of these are handled by the previous fix[1], but that's not sufficient
because it checks the DV it received against the DV it cached at the start
of the op, but the DV might've been updated in the meantime by a locally
generated modification op.
Fix this by the following means:
(1) Keep track of when we're performing a modification operation on a
vnode. This is done by marking vnode parameters with a 'modification'
note that causes the AFS_VNODE_MODIFYING flag to be set on the vnode
for the duration.
(2) Alter the speculation race detection to ignore speculative status
fetches if either the vnode is marked as being modified or the data
version number is not what we expected.
Note that whilst the "vnode modified" warning does get recovered from as it
causes the client to refetch the status at the next opportunity, it will
also invalidate the pagecache, so changes might get lost.
Fixes: a9e5c87ca744 ("afs: Fix speculative status fetch going out of order wrt to modifications")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-and-reviewed-by: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/160605082531.252452.14708077925602709042.stgit@warthog.procyon.org.uk/ [1]
Link: https://lore.kernel.org/linux-fsdevel/161961335926.39335.2552653972195467566.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 20:47:08 +08:00
|
|
|
if (op->file[0].modification)
|
|
|
|
|
clear_bit(AFS_VNODE_MODIFYING, &op->file[0].vnode->flags);
|
|
|
|
|
if (op->file[1].modification && op->file[1].vnode != op->file[0].vnode)
|
|
|
|
|
clear_bit(AFS_VNODE_MODIFYING, &op->file[1].vnode->flags);
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
if (op->file[0].put_vnode)
|
|
|
|
|
iput(&op->file[0].vnode->vfs_inode);
|
|
|
|
|
if (op->file[1].put_vnode)
|
|
|
|
|
iput(&op->file[1].vnode->vfs_inode);
|
|
|
|
|
|
|
|
|
|
if (op->more_files) {
|
|
|
|
|
for (i = 0; i < op->nr_files - 2; i++)
|
|
|
|
|
if (op->more_files[i].put_vnode)
|
|
|
|
|
iput(&op->more_files[i].vnode->vfs_inode);
|
|
|
|
|
kfree(op->more_files);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
afs_end_cursor(&op->ac);
|
|
|
|
|
afs_put_serverlist(op->net, op->server_list);
|
2020-04-30 00:02:04 +08:00
|
|
|
afs_put_volume(op->net, op->volume, afs_volume_trace_put_put_op);
|
2020-08-20 21:37:12 +08:00
|
|
|
key_put(op->key);
|
afs: Build an abstraction around an "operation" concept
Turn the afs_operation struct into the main way that most fileserver
operations are managed. Various things are added to the struct, including
the following:
(1) All the parameters and results of the relevant operations are moved
into it, removing corresponding fields from the afs_call struct.
afs_call gets a pointer to the op.
(2) The target volume is made the main focus of the operation, rather than
the target vnode(s), and a bunch of op->vnode->volume are made
op->volume instead.
(3) Two vnode records are defined (op->file[]) for the vnode(s) involved
in most operations. The vnode record (struct afs_vnode_param)
contains:
- The vnode pointer.
- The fid of the vnode to be included in the parameters or that was
returned in the reply (eg. FS.MakeDir).
- The status and callback information that may be returned in the
reply about the vnode.
- Callback break and data version tracking for detecting
simultaneous third-parth changes.
(4) Pointers to dentries to be updated with new inodes.
(5) An operations table pointer. The table includes pointers to functions
for issuing AFS and YFS-variant RPCs, handling the success and abort
of an operation and handling post-I/O-lock local editing of a
directory.
To make this work, the following function restructuring is made:
(A) The rotation loop that issues calls to fileservers that can be found
in each function that wants to issue an RPC (such as afs_mkdir()) is
extracted out into common code, in a new file called fs_operation.c.
(B) The rotation loops, such as the one in afs_mkdir(), are replaced with
a much smaller piece of code that allocates an operation, sets the
parameters and then calls out to the common code to do the actual
work.
(C) The code for handling the success and failure of an operation are
moved into operation functions (as (5) above) and these are called
from the core code at appropriate times.
(D) The pseudo inode getting stuff used by the dynamic root code is moved
over into dynroot.c.
(E) struct afs_iget_data is absorbed into the operation struct and
afs_iget() expects to be given an op pointer and a vnode record.
(F) Point (E) doesn't work for the root dir of a volume, but we know the
FID in advance (it's always vnode 1, unique 1), so a separate inode
getter, afs_root_iget(), is provided to special-case that.
(G) The inode status init/update functions now also take an op and a vnode
record.
(H) The RPC marshalling functions now, for the most part, just take an
afs_operation struct as their only argument. All the data they need
is held there. The result delivery functions write their answers
there as well.
(I) The call is attached to the operation and then the operation core does
the waiting.
And then the new operation code is, for the moment, made to just initialise
the operation, get the appropriate vnode I/O locks and do the same rotation
loop as before.
This lays the foundation for the following changes in the future:
(*) Overhauling the rotation (again).
(*) Support for asynchronous I/O, where the fileserver rotation must be
done asynchronously also.
Signed-off-by: David Howells <dhowells@redhat.com>
2020-04-11 03:51:51 +08:00
|
|
|
kfree(op);
|
|
|
|
|
return ret;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int afs_do_sync_operation(struct afs_operation *op)
|
|
|
|
|
{
|
|
|
|
|
afs_begin_vnode_operation(op);
|
|
|
|
|
afs_wait_for_operation(op);
|
|
|
|
|
return afs_put_operation(op);
|
|
|
|
|
}
|