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path: root/fs/afs/fs_probe.c (follow)
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* afs: Fix fileserver rotationDavid Howells2024-01-011-63/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the fileserver rotation so that it doesn't use RTT as the basis for deciding which server and address to use as this doesn't necessarily give a good indication of the best path. Instead, use the configurable preference list in conjunction with whatever probes have succeeded at the time of looking. To this end, make the following changes: (1) Keep an array of "server states" to track what addresses we've tried on each server and move the waitqueue entries there that we'll need for probing. (2) Each afs_server_state struct is made to pin the corresponding server's endpoint state rather than the afs_operation struct carrying a pin on the server we're currently looking at. (3) Drop the server list preference; we now always rescan the server list. (4) afs_wait_for_probes() now uses the server state list to guide it in what it waits for (and to provide the waitqueue entries) and returns an indication of whether we'd got a response, run out of responsive addresses or the endpoint state had been superseded and we need to restart the iteration. (5) Call afs_get_address_preferences*() occasionally to refresh the preference values. (6) When picking a server, scan the addresses of the servers for which we have as-yet untested communications, looking for the highest priority one and use that instead of trying all the addresses for a particular server in ascending-RTT order. (7) When a Busy or Offline state is seen across all available servers, do a short sleep. (8) If we detect that we accessed a future RO volume version whilst it is undergoing replication, reissue the op against the older version until at least half of the servers are replicated. (9) Whilst RO replication is ongoing, increase the frequency of Volume Location server checks for that volume to every ten minutes instead of hourly. Also add a tracepoint to track progress through the rotation algorithm. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Combine the endpoint state bools into a bitmaskDavid Howells2024-01-011-15/+15
| | | | | | | | | Combine the endpoint state bool-type members into a bitmask so that some of them can be waited upon more easily. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Keep a record of the current fileserver endpoint stateDavid Howells2024-01-011-92/+143
| | | | | | | | | | | | | | | | | | | Keep a record of the current fileserver endpoint state, including the probe state, and replace it when a new probe is started rather than just squelching the old state and overwriting it. Clearance of the old state can cause a race if there's another thread also currently trying to communicate with that server. It appears that this race might be the culprit for some occasions where kafs complains about invalid data in the RPC reply because the rotation algorithm fell all the way through without actually issuing an RPC call and the error return got filled in from the probe state (which has a zero error recorded). Whatever happens to be in the caller's reply buffer is then taken as the response. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Dispatch fileserver probes in priority orderDavid Howells2024-01-011-2/+23
| | | | | | | | | | | | When probing all the addresses for a fileserver, dispatch them in order of descending priority to try and get back highest priority one first. Also add a tracepoint to show the transmission and completion of the probes. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Add some more info to /proc/net/afs/serversDavid Howells2024-01-011-0/+2
| | | | | | | | | In /proc/net/afs/servers, show the cell name and the last error for each address in the server's list. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Fold the afs_addr_cursor struct inDavid Howells2023-12-241-22/+19
| | | | | | | | | Fold the afs_addr_cursor struct into the afs_operation struct and the afs_vl_cursor struct and fold its operations into their callers also. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Use peer + service_id as call addressDavid Howells2023-12-241-2/+2
| | | | | | | | | | | Use the rxrpc_peer plus the service ID as the call address instead of passing in a sockaddr_srx down to rxrpc. The peer record is obtained by using rxrpc_kernel_get_peer(). This avoids the need to repeatedly look up the peer and allows rxrpc to hold on to resources for it. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Add a tracepoint for struct afs_addr_listDavid Howells2023-12-241-2/+2
| | | | | | | | Add a tracepoint to track the lifetime of the afs_addr_list struct. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Rename addr_list::failed to probe_failedDavid Howells2023-12-241-3/+3
| | | | | | | | | Rename the failed member of struct addr_list to probe_failed as it's specifically related to probe failures. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* rxrpc, afs: Allow afs to pin rxrpc_peer objectsDavid Howells2023-12-241-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change rxrpc's API such that: (1) A new function, rxrpc_kernel_lookup_peer(), is provided to look up an rxrpc_peer record for a remote address and a corresponding function, rxrpc_kernel_put_peer(), is provided to dispose of it again. (2) When setting up a call, the rxrpc_peer object used during a call is now passed in rather than being set up by rxrpc_connect_call(). For afs, this meenat passing it to rxrpc_kernel_begin_call() rather than the full address (the service ID then has to be passed in as a separate parameter). (3) A new function, rxrpc_kernel_remote_addr(), is added so that afs can get a pointer to the transport address for display purposed, and another, rxrpc_kernel_remote_srx(), to gain a pointer to the full rxrpc address. (4) The function to retrieve the RTT from a call, rxrpc_kernel_get_srtt(), is then altered to take a peer. This now returns the RTT or -1 if there are insufficient samples. (5) Rename rxrpc_kernel_get_peer() to rxrpc_kernel_call_get_peer(). (6) Provide a new function, rxrpc_kernel_get_peer(), to get a ref on a peer the caller already has. This allows the afs filesystem to pin the rxrpc_peer records that it is using, allowing faster lookups and pointer comparisons rather than comparing sockaddr_rxrpc contents. It also makes it easier to get hold of the RTT. The following changes are made to afs: (1) The addr_list struct's addrs[] elements now hold a peer struct pointer and a service ID rather than a sockaddr_rxrpc. (2) When displaying the transport address, rxrpc_kernel_remote_addr() is used. (3) The port arg is removed from afs_alloc_addrlist() since it's always overridden. (4) afs_merge_fs_addr4() and afs_merge_fs_addr6() do peer lookup and may now return an error that must be handled. (5) afs_find_server() now takes a peer pointer to specify the address. (6) afs_find_server(), afs_compare_fs_alists() and afs_merge_fs_addr[46]{} now do peer pointer comparison rather than address comparison. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Turn the afs_addr_list address array into an array of structsDavid Howells2023-12-241-3/+3
| | | | | | | | | Turn the afs_addr_list address array into an array of structs, thereby allowing per-address (such as RTT) info to be added. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
* afs: Fix lost servers_outstanding countDavid Howells2022-12-221-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | The afs_fs_probe_dispatcher() work function is passed a count on net->servers_outstanding when it is scheduled (which may come via its timer). This is passed back to the work_item, passed to the timer or dropped at the end of the dispatcher function. But, at the top of the dispatcher function, there are two checks which skip the rest of the function: if the network namespace is being destroyed or if there are no fileservers to probe. These two return paths, however, do not drop the count passed to the dispatcher, and so, sometimes, the destruction of a network namespace, such as induced by rmmod of the kafs module, may get stuck in afs_purge_servers(), waiting for net->servers_outstanding to become zero. Fix this by adding the missing decrements in afs_fs_probe_dispatcher(). Fixes: f6cbb368bcb0 ("afs: Actively poll fileservers to maintain NAT or firewall openings") Reported-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/167164544917.2072364.3759519569649459359.stgit@warthog.procyon.org.uk/
* afs: Fix fileserver probe RTT handlingDavid Howells2022-11-291-2/+2
| | | | | | | | | | | | | | | | | | | | | The fileserver probing code attempts to work out the best fileserver to use for a volume by retrieving the RTT calculated by AF_RXRPC for the probe call sent to each server and comparing them. Sometimes, however, no RTT estimate is available and rxrpc_kernel_get_srtt() returns false, leading good fileservers to be given an RTT of UINT_MAX and thus causing the rotation algorithm to ignore them. Fix afs_select_fileserver() to ignore rxrpc_kernel_get_srtt()'s return value and just take the estimated RTT it provides - which will be capped at 1 second. Fixes: 1d4adfaf6574 ("rxrpc: Make rxrpc_kernel_get_srtt() indicate validity") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Tested-by: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/166965503999.3392585.13954054113218099395.stgit@warthog.procyon.org.uk/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* afs: Fix corruption in reads at fpos 2G-4G from an OpenAFS serverDavid Howells2021-09-131-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AFS-3 has two data fetch RPC variants, FS.FetchData and FS.FetchData64, and Linux's afs client switches between them when talking to a non-YFS server if the read size, the file position or the sum of the two have the upper 32 bits set of the 64-bit value. This is a problem, however, since the file position and length fields of FS.FetchData are *signed* 32-bit values. Fix this by capturing the capability bits obtained from the fileserver when it's sent an FS.GetCapabilities RPC, rather than just discarding them, and then picking out the VICED_CAPABILITY_64BITFILES flag. This can then be used to decide whether to use FS.FetchData or FS.FetchData64 - and also FS.StoreData or FS.StoreData64 - rather than using upper_32_bits() to switch on the parameter values. This capabilities flag could also be used to limit the maximum size of the file, but all servers must be checked for that. Note that the issue does not exist with FS.StoreData - that uses *unsigned* 32-bit values. It's also not a problem with Auristor servers as its YFS.FetchData64 op uses unsigned 64-bit values. This can be tested by cloning a git repo through an OpenAFS client to an OpenAFS server and then doing "git status" on it from a Linux afs client[1]. Provided the clone has a pack file that's in the 2G-4G range, the git status will show errors like: error: packfile .git/objects/pack/pack-5e813c51d12b6847bbc0fcd97c2bca66da50079c.pack does not match index error: packfile .git/objects/pack/pack-5e813c51d12b6847bbc0fcd97c2bca66da50079c.pack does not match index This can be observed in the server's FileLog with something like the following appearing: Sun Aug 29 19:31:39 2021 SRXAFS_FetchData, Fid = 2303380852.491776.3263114, Host 192.168.11.201:7001, Id 1001 Sun Aug 29 19:31:39 2021 CheckRights: len=0, for host=192.168.11.201:7001 Sun Aug 29 19:31:39 2021 FetchData_RXStyle: Pos 18446744071815340032, Len 3154 Sun Aug 29 19:31:39 2021 FetchData_RXStyle: file size 2400758866 ... Sun Aug 29 19:31:40 2021 SRXAFS_FetchData returns 5 Note the file position of 18446744071815340032. This is the requested file position sign-extended. Fixes: b9b1f8d5930a ("AFS: write support fixes") Reported-by: Markus Suvanto <markus.suvanto@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Tested-by: Markus Suvanto <markus.suvanto@gmail.com> cc: linux-afs@lists.infradead.org cc: openafs-devel@openafs.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=214217#c9 [1] Link: https://lore.kernel.org/r/951332.1631308745@warthog.procyon.org.uk/
* rxrpc: Make rxrpc_kernel_get_srtt() indicate validityDavid Howells2020-08-201-2/+2
| | | | | | | | | Fix rxrpc_kernel_get_srtt() to indicate the validity of the returned smoothed RTT. If we haven't had any valid samples yet, the SRTT isn't useful. Fixes: c410bf01933e ("rxrpc: Fix the excessive initial retransmission timeout") Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Fix hang on rmmod due to outstanding timerDavid Howells2020-06-201-1/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fileserver probe timer, net->fs_probe_timer, isn't cancelled when the kafs module is being removed and so the count it holds on net->servers_outstanding doesn't get dropped.. This causes rmmod to wait forever. The hung process shows a stack like: afs_purge_servers+0x1b5/0x23c [kafs] afs_net_exit+0x44/0x6e [kafs] ops_exit_list+0x72/0x93 unregister_pernet_operations+0x14c/0x1ba unregister_pernet_subsys+0x1d/0x2a afs_exit+0x29/0x6f [kafs] __do_sys_delete_module.isra.0+0x1a2/0x24b do_syscall_64+0x51/0x95 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fix this by: (1) Attempting to cancel the probe timer and, if successful, drop the count that the timer was holding. (2) Make the timer function just drop the count and not schedule the prober if the afs portion of net namespace is being destroyed. Also, whilst we're at it, make the following changes: (3) Initialise net->servers_outstanding to 1 and decrement it before waiting on it so that it doesn't generate wake up events by being decremented to 0 until we're cleaning up. (4) Switch the atomic_dec() on ->servers_outstanding for ->fs_timer in afs_purge_servers() to use the helper function for that. Fixes: f6cbb368bcb0 ("afs: Actively poll fileservers to maintain NAT or firewall openings") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* afs: Adjust the fileserver rotation algorithm to reprobe/retry more quicklyDavid Howells2020-06-041-0/+47
| | | | | | | | | | Adjust the fileserver rotation algorithm so that if we've tried all the addresses on a server (cumulatively over multiple operations) until we've run out of untried addresses, immediately reprobe all that server's interfaces and retry the op at least once before we move onto the next server. Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Don't use probe running state to make decisions outside probe codeDavid Howells2020-06-041-6/+12
| | | | | | | | | | | | Don't use the running state for fileserver probes to make decisions about which server to use as the state is cleared at the start of a probe and also intermediate values might be misleading. Instead, add a separate 'latest known' rtt in the afs_server struct and a flag to indicate if the server is known to be responding and update these as and when we know what to change them to. Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Actively poll fileservers to maintain NAT or firewall openingsDavid Howells2020-05-311-68/+209
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an AFS client accesses a file, it receives a limited-duration callback promise that the server will notify it if another client changes a file. This callback duration can be a few hours in length. If a client mounts a volume and then an application prevents it from being unmounted, say by chdir'ing into it, but then does nothing for some time, the rxrpc_peer record will expire and rxrpc-level keepalive will cease. If there is NAT or a firewall between the client and the server, the route back for the server may close after a comparatively short duration, meaning that attempts by the server to notify the client may then bounce. The client, however, may (so far as it knows) still have a valid unexpired promise and will then rely on its cached data and will not see changes made on the server by a third party until it incidentally rechecks the status or the promise needs renewal. To deal with this, the client needs to regularly probe the server. This has two effects: firstly, it keeps a route open back for the server, and secondly, it causes the server to disgorge any notifications that got queued up because they couldn't be sent. Fix this by adding a mechanism to emit regular probes. Two levels of probing are made available: Under normal circumstances the 'slow' queue will be used for a fileserver - this just probes the preferred address once every 5 mins or so; however, if server fails to respond to any probes, the server will shift to the 'fast' queue from which all its interfaces will be probed every 30s. When it finally responds, the record will switch back to the slow queue. Further notes: (1) Probing is now no longer driven from the fileserver rotation algorithm. (2) Probes are dispatched to all interfaces on a fileserver when that an afs_server object is set up to record it. (3) The afs_server object is removed from the probe queues when we start to probe it. afs_is_probing_server() returns true if it's not listed - ie. it's undergoing probing. (4) The afs_server object is added back on to the probe queue when the final outstanding probe completes, but the probed_at time is set when we're about to launch a probe so that it's not dependent on the probe duration. (5) The timer and the work item added for this must be handed a count on net->servers_outstanding, which they hand on or release. This makes sure that network namespace cleanup waits for them. Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation") Reported-by: Dave Botsch <botsch@cnf.cornell.edu> Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Split the usage count on struct afs_serverDavid Howells2020-05-311-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split the usage count on the afs_server struct to have an active count that registers who's actually using it separately from the reference count on the object. This allows a future patch to dispatch polling probes without advancing the "unuse" time into the future each time we emit a probe, which would otherwise prevent unused server records from expiring. Included in this: (1) The latter part of afs_destroy_server() in which the RCU destruction of afs_server objects is invoked and the outstanding server count is decremented is split out into __afs_put_server(). (2) afs_put_server() now calls __afs_put_server() rather then setting the management timer. (3) The calls begun by afs_fs_give_up_all_callbacks() and afs_fs_get_capabilities() can now take a ref on the server record, so afs_destroy_server() can just drop its ref and needn't wait for the completion of these calls. They'll put the ref when they're done. (4) Because of (3), afs_fs_probe_done() no longer needs to wake up afs_destroy_server() with server->probe_outstanding. (5) afs_gc_servers can be simplified. It only needs to check if server->active is 0 rather than playing games with the refcount. (6) afs_manage_servers() can propose a server for gc if usage == 0 rather than if ref == 1. The gc is effected by (5). Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix a warningDavid Howells2020-05-231-1/+1
| | | | | | | | | | | | | Fix a warning due to an uninitialised variable. le included from ../fs/afs/fs_probe.c:11: ../fs/afs/fs_probe.c: In function 'afs_fileserver_probe_result': ../fs/afs/internal.h:1453:2: warning: 'rtt_us' may be used uninitialized in this function [-Wmaybe-uninitialized] 1453 | printk("[%-6.6s] "FMT"\n", current->comm ,##__VA_ARGS__) | ^~~~~~ ../fs/afs/fs_probe.c:35:15: note: 'rtt_us' was declared here Signed-off-by: David Howells <dhowells@redhat.com>
* rxrpc: Fix the excessive initial retransmission timeoutDavid Howells2020-05-111-13/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rxrpc currently uses a fixed 4s retransmission timeout until the RTT is sufficiently sampled. This can cause problems with some fileservers with calls to the cache manager in the afs filesystem being dropped from the fileserver because a packet goes missing and the retransmission timeout is greater than the call expiry timeout. Fix this by: (1) Copying the RTT/RTO calculation code from Linux's TCP implementation and altering it to fit rxrpc. (2) Altering the various users of the RTT to make use of the new SRTT value. (3) Replacing the use of rxrpc_resend_timeout to use the calculated RTO value instead (which is needed in jiffies), along with a backoff. Notes: (1) rxrpc provides RTT samples by matching the serial numbers on outgoing DATA packets that have the RXRPC_REQUEST_ACK set and PING ACK packets against the reference serial number in incoming REQUESTED ACK and PING-RESPONSE ACK packets. (2) Each packet that is transmitted on an rxrpc connection gets a new per-connection serial number, even for retransmissions, so an ACK can be cross-referenced to a specific trigger packet. This allows RTT information to be drawn from retransmitted DATA packets also. (3) rxrpc maintains the RTT/RTO state on the rxrpc_peer record rather than on an rxrpc_call because many RPC calls won't live long enough to generate more than one sample. (4) The calculated SRTT value is in units of 8ths of a microsecond rather than nanoseconds. The (S)RTT and RTO values are displayed in /proc/net/rxrpc/peers. Fixes: 17926a79320a ([AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both"") Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Remove some unused bitsDavid Howells2020-04-241-4/+1
| | | | | | | | | | | | | | Remove three bits: (1) afs_server::no_epoch is neither set nor used. (2) afs_server::have_result is set and a wakeup is applied to it, but nothing looks at it or waits on it. (3) afs_vl_dump_edestaddrreq() prints afs_addr_list::probed, but nothing sets it for VL servers. Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Fix unpinned address list during probingDavid Howells2020-03-271-0/+2
| | | | | | | | | | | | | | | | | | When it's probing all of a fileserver's interfaces to find which one is best to use, afs_do_probe_fileserver() takes a lock on the server record and notes the pointer to the address list. It doesn't, however, pin the address list, so as soon as it drops the lock, there's nothing to stop the address list from being freed under us. Fix this by taking a ref on the address list inside the locked section and dropping it at the end of the function. Fixes: 3bf0fb6f33dd ("afs: Probe multiple fileservers simultaneously") Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36Thomas Gleixner2019-05-241-5/+1
| | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public licence as published by the free software foundation either version 2 of the licence or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 114 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* afs: Get rid of afs_call::reply[]David Howells2019-05-161-2/+2
| | | | | | | | Replace the afs_call::reply[] array with a bunch of typed members so that the compiler can use type-checking on them. It's also easier for the eye to see what's going on. Signed-off-by: David Howells <dhowells@redhat.com>
* afs: Split wait from afs_make_call()David Howells2019-04-251-6/+7
| | | | | | | | | Split the call to afs_wait_for_call_to_complete() from afs_make_call() to make it easier to handle asynchronous calls and to make it easier to convert a synchronous call to an asynchronous one in future, for instance when someone tries to interrupt an operation by pressing Ctrl-C. Signed-off-by: David Howells <dhowells@redhat.com>
* fs/: remove caller signal_pending branch predictionsDavidlohr Bueso2019-01-041-1/+1
| | | | | | | | | | | This is already done for us internally by the signal machinery. [akpm@linux-foundation.org: fix fs/buffer.c] Link: http://lkml.kernel.org/r/20181116002713.8474-7-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* afs: Fix missing net error handlingDavid Howells2018-11-301-15/+24
| | | | | | | | | | | | | | | | | | | | | | | kAFS can be given certain network errors (EADDRNOTAVAIL, EHOSTDOWN and ERFKILL) that it doesn't handle in its server/address rotation algorithms. They cause the probing and rotation to abort immediately rather than rotating. Fix this by: (1) Abstracting out the error prioritisation from the VL and FS rotation algorithms into a common function and expand usage into the server probing code. When multiple errors are available, this code selects the one we'd prefer to return. (2) Add handling for EADDRNOTAVAIL, EHOSTDOWN and ERFKILL. Fixes: 0fafdc9f888b ("afs: Fix file locking") Fixes: 0338747d8454 ("afs: Probe multiple fileservers simultaneously") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* afs: Probe multiple fileservers simultaneouslyDavid Howells2018-10-241-0/+270
Send probes to all the unprobed fileservers in a fileserver list on all addresses simultaneously in an attempt to find out the fastest route whilst not getting stuck for 20s on any server or address that we don't get a reply from. This alleviates the problem whereby attempting to access a new server can take a long time because the rotation algorithm ends up rotating through all servers and addresses until it finds one that responds. Signed-off-by: David Howells <dhowells@redhat.com>