afs: Make some RPC operations non-interruptible

Make certain RPC operations non-interruptible, including:

 (*) Set attributes
 (*) Store data

     We don't want to get interrupted during a flush on close, flush on
     unlock, writeback or an inode update, leaving us in a state where we
     still need to do the writeback or update.

 (*) Extend lock
 (*) Release lock

     We don't want to get lock extension interrupted as the file locks on
     the server are time-limited.  Interruption during lock release is less
     of an issue since the lock is time-limited, but it's better to
     complete the release to avoid a several-minute wait to recover it.

     *Setting* the lock isn't a problem if it's interrupted since we can
      just return to the user and tell them they were interrupted - at
      which point they can elect to retry.

 (*) Silly unlink

     We want to remove silly unlink files if we can, rather than leaving
     them for the salvager to clear up.

Note that whilst these calls are no longer interruptible, they do have
timeouts on them, so if the server stops responding the call will fail with
something like ETIME or ECONNRESET.

Without this, the following:

	kAFS: Unexpected error from FS.StoreData -512

appears in dmesg when a pending store data gets interrupted and some
processes may just hang.

Additionally, make the code that checks/updates the server record ignore
failure due to interruption if the main call is uninterruptible and if the
server has an address list.  The next op will check it again since the
expiration time on the old list has past.

Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 7051b58d8a55..d58848c357aa 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -469,6 +469,7 @@ int afs_fs_fetch_file_status(struct afs_fs_cursor *fc, struct afs_volsync *volsy
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
 
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -664,6 +665,7 @@ static int afs_fs_fetch_data64(struct afs_fs_cursor *fc, struct afs_read *req)
 	call->cb_break = fc->cb_break;
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -712,6 +714,7 @@ int afs_fs_fetch_data(struct afs_fs_cursor *fc, struct afs_read *req)
 	call->cb_break = fc->cb_break;
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -833,6 +836,7 @@ int afs_fs_create(struct afs_fs_cursor *fc,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call1(call, &vnode->fid, name);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -930,6 +934,7 @@ int afs_fs_remove(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call1(call, &dvnode->fid, name);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1023,6 +1028,7 @@ int afs_fs_link(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call1(call, &vnode->fid, name);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1138,6 +1144,7 @@ int afs_fs_symlink(struct afs_fs_cursor *fc,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call1(call, &vnode->fid, name);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1257,6 +1264,7 @@ int afs_fs_rename(struct afs_fs_cursor *fc,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call2(call, &orig_dvnode->fid, orig_name, new_name);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1362,6 +1370,7 @@ static int afs_fs_store_data64(struct afs_fs_cursor *fc,
 	*bp++ = htonl((u32) i_size);
 
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1439,6 +1448,7 @@ int afs_fs_store_data(struct afs_fs_cursor *fc, struct address_space *mapping,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1538,6 +1548,7 @@ static int afs_fs_setattr_size64(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1585,6 +1596,7 @@ static int afs_fs_setattr_size(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1630,6 +1642,7 @@ int afs_fs_setattr(struct afs_fs_cursor *fc, struct iattr *attr)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1815,6 +1828,7 @@ int afs_fs_get_volume_status(struct afs_fs_cursor *fc,
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1906,6 +1920,7 @@ int afs_fs_set_lock(struct afs_fs_cursor *fc, afs_lock_type_t type)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_calli(call, &vnode->fid, type);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1942,6 +1957,7 @@ int afs_fs_extend_lock(struct afs_fs_cursor *fc)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -1977,6 +1993,7 @@ int afs_fs_release_lock(struct afs_fs_cursor *fc)
 
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &vnode->fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -2211,6 +2228,7 @@ int afs_fs_fetch_status(struct afs_fs_cursor *fc,
 	call->cb_break = fc->cb_break;
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, fid);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }
@@ -2397,6 +2415,7 @@ int afs_fs_inline_bulk_status(struct afs_fs_cursor *fc,
 	call->cb_break = fc->cb_break;
 	afs_use_fs_server(call, fc->cbi);
 	trace_afs_make_fs_call(call, &fids[0]);
+	afs_set_fc_call(call, fc);
 	afs_make_call(&fc->ac, call, GFP_NOFS);
 	return afs_wait_for_call_to_complete(call, &fc->ac);
 }