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netfs, afs: Use writeback retry to deal with alternate keys

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Use a hook in the new writeback code's retry algorithm to rotate the keys
once all the outstanding subreqs have failed rather than doing it
separately on each subreq.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
This commit is contained in:
David Howells 2024-03-15 15:15:44 +00:00
parent d41ca44c20
commit 1ecb146f7c
5 changed files with 112 additions and 108 deletions
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1
fs/afs/file.c
View File

@ -368,6 +368,7 @@ static int afs_check_write_begin(struct file *file, loff_t pos, unsigned len,
static void afs_free_request(struct netfs_io_request *rreq)
{
key_put(rreq->netfs_priv);
afs_put_wb_key(rreq->netfs_priv2);
}
static void afs_update_i_size(struct inode *inode, loff_t new_i_size)

1
fs/afs/internal.h
View File

@ -1601,6 +1601,7 @@ extern int afs_check_volume_status(struct afs_volume *, struct afs_operation *);
void afs_prepare_write(struct netfs_io_subrequest *subreq);
void afs_issue_write(struct netfs_io_subrequest *subreq);
void afs_begin_writeback(struct netfs_io_request *wreq);
void afs_retry_request(struct netfs_io_request *wreq, struct netfs_io_stream *stream);
extern int afs_writepages(struct address_space *, struct writeback_control *);
extern int afs_fsync(struct file *, loff_t, loff_t, int);
extern vm_fault_t afs_page_mkwrite(struct vm_fault *vmf);

207
fs/afs/write.c
View File

@ -29,43 +29,39 @@ static void afs_pages_written_back(struct afs_vnode *vnode, loff_t start, unsign
/*
* Find a key to use for the writeback. We cached the keys used to author the
* writes on the vnode. *_wbk will contain the last writeback key used or NULL
* and we need to start from there if it's set.
* writes on the vnode. wreq->netfs_priv2 will contain the last writeback key
* record used or NULL and we need to start from there if it's set.
* wreq->netfs_priv will be set to the key itself or NULL.
*/
static int afs_get_writeback_key(struct afs_vnode *vnode,
struct afs_wb_key **_wbk)
static void afs_get_writeback_key(struct netfs_io_request *wreq)
{
struct afs_wb_key *wbk = NULL;
struct list_head *p;
int ret = -ENOKEY, ret2;
struct afs_wb_key *wbk, *old = wreq->netfs_priv2;
struct afs_vnode *vnode = AFS_FS_I(wreq->inode);
key_put(wreq->netfs_priv);
wreq->netfs_priv = NULL;
wreq->netfs_priv2 = NULL;
spin_lock(&vnode->wb_lock);
if (*_wbk)
p = (*_wbk)->vnode_link.next;
if (old)
wbk = list_next_entry(old, vnode_link);
else
p = vnode->wb_keys.next;
wbk = list_first_entry(&vnode->wb_keys, struct afs_wb_key, vnode_link);
while (p != &vnode->wb_keys) {
wbk = list_entry(p, struct afs_wb_key, vnode_link);
list_for_each_entry_from(wbk, &vnode->wb_keys, vnode_link) {
_debug("wbk %u", key_serial(wbk->key));
ret2 = key_validate(wbk->key);
if (ret2 == 0) {
if (key_validate(wbk->key) == 0) {
refcount_inc(&wbk->usage);
wreq->netfs_priv = key_get(wbk->key);
wreq->netfs_priv2 = wbk;
_debug("USE WB KEY %u", key_serial(wbk->key));
break;
}
wbk = NULL;
if (ret == -ENOKEY)
ret = ret2;
p = p->next;
}
spin_unlock(&vnode->wb_lock);
if (*_wbk)
afs_put_wb_key(*_wbk);
*_wbk = wbk;
return 0;
afs_put_wb_key(old);
}
static void afs_store_data_success(struct afs_operation *op)
@ -87,84 +83,6 @@ static const struct afs_operation_ops afs_store_data_operation = {
.success = afs_store_data_success,
};
/*
* write to a file
*/
static int afs_store_data(struct afs_vnode *vnode, struct iov_iter *iter, loff_t pos)
{
struct afs_operation *op;
struct afs_wb_key *wbk = NULL;
loff_t size = iov_iter_count(iter);
int ret = -ENOKEY;
_enter("%s{%llx:%llu.%u},%llx,%llx",
vnode->volume->name,
vnode->fid.vid,
vnode->fid.vnode,
vnode->fid.unique,
size, pos);
ret = afs_get_writeback_key(vnode, &wbk);
if (ret) {
_leave(" = %d [no keys]", ret);
return ret;
}
op = afs_alloc_operation(wbk->key, vnode->volume);
if (IS_ERR(op)) {
afs_put_wb_key(wbk);
return -ENOMEM;
}
afs_op_set_vnode(op, 0, vnode);
op->file[0].dv_delta = 1;
op->file[0].modification = true;
op->store.pos = pos;
op->store.size = size;
op->flags |= AFS_OPERATION_UNINTR;
op->ops = &afs_store_data_operation;
try_next_key:
afs_begin_vnode_operation(op);
op->store.write_iter = iter;
op->store.i_size = max(pos + size, vnode->netfs.remote_i_size);
op->mtime = inode_get_mtime(&vnode->netfs.inode);
afs_wait_for_operation(op);
switch (afs_op_error(op)) {
case -EACCES:
case -EPERM:
case -ENOKEY:
case -EKEYEXPIRED:
case -EKEYREJECTED:
case -EKEYREVOKED:
_debug("next");
ret = afs_get_writeback_key(vnode, &wbk);
if (ret == 0) {
key_put(op->key);
op->key = key_get(wbk->key);
goto try_next_key;
}
break;
}
afs_put_wb_key(wbk);
_leave(" = %d", afs_op_error(op));
return afs_put_operation(op);
}
/*
* Writeback calls this when it finds a folio that needs uploading. This isn't
* called if writeback only has copy-to-cache to deal with.
*/
void afs_begin_writeback(struct netfs_io_request *wreq)
{
wreq->io_streams[0].avail = true;
}
/*
* Prepare a subrequest to write to the server. This sets the max_len
* parameter.
@ -183,11 +101,20 @@ void afs_prepare_write(struct netfs_io_subrequest *subreq)
static void afs_issue_write_worker(struct work_struct *work)
{
struct netfs_io_subrequest *subreq = container_of(work, struct netfs_io_subrequest, work);
struct afs_vnode *vnode = AFS_FS_I(subreq->rreq->inode);
ssize_t ret;
struct netfs_io_request *wreq = subreq->rreq;
struct afs_operation *op;
struct afs_vnode *vnode = AFS_FS_I(wreq->inode);
unsigned long long pos = subreq->start + subreq->transferred;
size_t len = subreq->len - subreq->transferred;
int ret = -ENOKEY;
_enter("%x[%x],%zx",
subreq->rreq->debug_id, subreq->debug_index, subreq->io_iter.count);
_enter("R=%x[%x],%s{%llx:%llu.%u},%llx,%zx",
wreq->debug_id, subreq->debug_index,
vnode->volume->name,
vnode->fid.vid,
vnode->fid.vnode,
vnode->fid.unique,
pos, len);
#if 0 // Error injection
if (subreq->debug_index == 3)
@ -199,7 +126,41 @@ static void afs_issue_write_worker(struct work_struct *work)
}
#endif
ret = afs_store_data(vnode, &subreq->io_iter, subreq->start);
op = afs_alloc_operation(wreq->netfs_priv, vnode->volume);
if (IS_ERR(op))
return netfs_write_subrequest_terminated(subreq, -EAGAIN, false);
afs_op_set_vnode(op, 0, vnode);
op->file[0].dv_delta = 1;
op->file[0].modification = true;
op->store.pos = pos;
op->store.size = len;
op->flags |= AFS_OPERATION_UNINTR;
op->ops = &afs_store_data_operation;
afs_begin_vnode_operation(op);
op->store.write_iter = &subreq->io_iter;
op->store.i_size = umax(pos + len, vnode->netfs.remote_i_size);
op->mtime = inode_get_mtime(&vnode->netfs.inode);
afs_wait_for_operation(op);
ret = afs_put_operation(op);
switch (ret) {
case -EACCES:
case -EPERM:
case -ENOKEY:
case -EKEYEXPIRED:
case -EKEYREJECTED:
case -EKEYREVOKED:
/* If there are more keys we can try, use the retry algorithm
* to rotate the keys.
*/
if (wreq->netfs_priv2)
set_bit(NETFS_SREQ_NEED_RETRY, &subreq->flags);
break;
}
netfs_write_subrequest_terminated(subreq, ret < 0 ? ret : subreq->len, false);
}
@ -210,6 +171,40 @@ void afs_issue_write(struct netfs_io_subrequest *subreq)
WARN_ON_ONCE(1);
}
/*
* Writeback calls this when it finds a folio that needs uploading. This isn't
* called if writeback only has copy-to-cache to deal with.
*/
void afs_begin_writeback(struct netfs_io_request *wreq)
{
afs_get_writeback_key(wreq);
wreq->io_streams[0].avail = true;
}
/*
* Prepare to retry the writes in request. Use this to try rotating the
* available writeback keys.
*/
void afs_retry_request(struct netfs_io_request *wreq, struct netfs_io_stream *stream)
{
struct netfs_io_subrequest *subreq =
list_first_entry(&stream->subrequests,
struct netfs_io_subrequest, rreq_link);
switch (subreq->error) {
case -EACCES:
case -EPERM:
case -ENOKEY:
case -EKEYEXPIRED:
case -EKEYREJECTED:
case -EKEYREVOKED:
afs_get_writeback_key(wreq);
if (!wreq->netfs_priv)
stream->failed = true;
break;
}
}
/*
* write some of the pending data back to the server
*/

9
fs/netfs/write_collect.c
View File

@ -163,6 +163,13 @@ static void netfs_retry_write_stream(struct netfs_io_request *wreq,
_enter("R=%x[%x:]", wreq->debug_id, stream->stream_nr);
if (list_empty(&stream->subrequests))
return;
if (stream->source == NETFS_UPLOAD_TO_SERVER &&
wreq->netfs_ops->retry_request)
wreq->netfs_ops->retry_request(wreq, stream);
if (unlikely(stream->failed))
return;
@ -182,8 +189,6 @@ static void netfs_retry_write_stream(struct netfs_io_request *wreq,
return;
}
if (list_empty(&stream->subrequests))
return;
next = stream->subrequests.next;
do {

2
include/linux/netfs.h
View File

@ -235,6 +235,7 @@ struct netfs_io_request {
struct iov_iter iter; /* Unencrypted-side iterator */
struct iov_iter io_iter; /* I/O (Encrypted-side) iterator */
void *netfs_priv; /* Private data for the netfs */
void *netfs_priv2; /* Private data for the netfs */
struct bio_vec *direct_bv; /* DIO buffer list (when handling iovec-iter) */
unsigned int direct_bv_count; /* Number of elements in direct_bv[] */
unsigned int debug_id;
@ -306,6 +307,7 @@ struct netfs_request_ops {
void (*begin_writeback)(struct netfs_io_request *wreq);
void (*prepare_write)(struct netfs_io_subrequest *subreq);
void (*issue_write)(struct netfs_io_subrequest *subreq);
void (*retry_request)(struct netfs_io_request *wreq, struct netfs_io_stream *stream);
void (*invalidate_cache)(struct netfs_io_request *wreq);
};