summaryrefslogtreecommitdiffstats
path: root/fs/afs/internal.h
AgeCommit message (Collapse)AuthorFilesLines
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner1-5/+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 license as published by the free software foundation either version 2 of the license 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 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-16afs: Pass pre-fetch server and volume break counts into afs_iget5_set()David Howells1-1/+3
Pass the server and volume break counts from before the status fetch operation that queried the attributes of a file into afs_iget5_set() so that the new vnode's break counters can be initialised appropriately. This allows detection of a volume or server break that happened whilst we were fetching the status or setting up the vnode. Fixes: c435ee34551e ("afs: Overhaul the callback handling") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Fix unlink to handle YFS.RemoveFile2 betterDavid Howells1-1/+0
Make use of the status update for the target file that the YFS.RemoveFile2 RPC op returns to correctly update the vnode as to whether the file was actually deleted or just had nlink reduced. Fixes: 30062bd13e36 ("afs: Implement YFS support in the fs client") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Make vnode->cb_interest RCU safeDavid Howells1-3/+9
Use RCU-based freeing for afs_cb_interest struct objects and use RCU on vnode->cb_interest. Use that change to allow afs_check_validity() to use read_seqbegin_or_lock() instead of read_seqlock_excl(). This also requires the caller of afs_check_validity() to hold the RCU read lock across the call. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Split afs_validate() so first part can be used under LOOKUP_RCUDavid Howells1-0/+1
Split afs_validate() so that the part that decides if the vnode is still valid can be used under LOOKUP_RCU conditions from afs_d_revalidate(). Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Don't save callback version and type fieldsDavid Howells1-2/+0
Don't save callback version and type fields as the version is about the format of the callback information and the type is relative to the particular RPC call. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Fix application of status and callback to be under same lockDavid Howells1-68/+66
When applying the status and callback in the response of an operation, apply them in the same critical section so that there's no race between checking the callback state and checking status-dependent state (such as the data version). Fix this by: (1) Allocating a joint {status,callback} record (afs_status_cb) before calling the RPC function for each vnode for which the RPC reply contains a status or a status plus a callback. A flag is set in the record to indicate if a callback was actually received. (2) These records are passed into the RPC functions to be filled in. The afs_decode_status() and yfs_decode_status() functions are removed and the cb_lock is no longer taken. (3) xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() no longer update the vnode. (4) xdr_decode_AFSCallBack() and xdr_decode_YFSCallBack() no longer update the vnode. (5) vnodes, expected data-version numbers and callback break counters (cb_break) no longer need to be passed to the reply delivery functions. Note that, for the moment, the file locking functions still need access to both the call and the vnode at the same time. (6) afs_vnode_commit_status() is now given the cb_break value and the expected data_version and the task of applying the status and the callback to the vnode are now done here. This is done under a single taking of vnode->cb_lock. (7) afs_pages_written_back() is now called by afs_store_data() rather than by the reply delivery function. afs_pages_written_back() has been moved to before the call point and is now given the first and last page numbers rather than a pointer to the call. (8) The indicator from YFS.RemoveFile2 as to whether the target file actually got removed (status.abort_code == VNOVNODE) rather than merely dropping a link is now checked in afs_unlink rather than in xdr_decode_YFSFetchStatus(). Supplementary fixes: (*) afs_cache_permit() now gets the caller_access mask from the afs_status_cb object rather than picking it out of the vnode's status record. afs_fetch_status() returns caller_access through its argument list for this purpose also. (*) afs_inode_init_from_status() now uses a write lock on cb_lock rather than a read lock and now sets the callback inside the same critical section. Fixes: c435ee34551e ("afs: Overhaul the callback handling") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Always get the reply timeDavid Howells1-1/+1
Always ask for the reply time from AF_RXRPC as it's used to calculate the callback expiry time and lock expiry times, so it's needed by most FS operations. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Fix order-1 allocation in afs_do_lookup()David Howells1-6/+5
afs_do_lookup() will do an order-1 allocation to allocate status records if there are more than 39 vnodes to stat. Fix this by allocating an array of {status,callback} records for each vnode we want to examine using vmalloc() if larger than a page. This not only gets rid of the order-1 allocation, but makes it easier to grow beyond 50 records for YFS servers. It also allows us to move to {status,callback} tuples for other calls too and makes it easier to lock across the application of the status and the callback to the vnode. Fixes: 5cf9dd55a0ec ("afs: Prospectively look up extra files when doing a single lookup") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Get rid of afs_call::reply[]David Howells1-3/+21
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>
2019-05-16afs: Make some RPC operations non-interruptibleDavid Howells1-1/+8
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>
2019-05-16afs: Fix the maximum lifespan of VL and probe callsDavid Howells1-0/+1
If an older AFS server doesn't support an operation, it may accept the call and then sit on it forever, happily responding to pings that make kafs think that the call is still alive. Fix this by setting the maximum lifespan of Volume Location service calls in particular and probe calls in general so that they don't run on endlessly if they're not supported. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-16afs: Fix cell DNS lookupDavid Howells1-5/+5
Currently, once configured, AFS cells are looked up in the DNS at regular intervals - which is a waste of resources if those cells aren't being used. It also leads to a problem where cells preloaded, but not configured, before the network is brought up end up effectively statically configured with no VL servers and are unable to get any. Fix this by not doing the DNS lookup until the first time a cell is touched. It is waited for if we don't have any cached records yet, otherwise the DNS lookup to maintain the record is done in the background. This has the downside that the first time you touch a cell, you now have to wait for the upcall to do the required DNS lookups rather than them already being cached. Further, the record is not replaced if the old record has at least one server in it and the new record doesn't have any. Fixes: 0a5143f2f89c ("afs: Implement VL server rotation") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-15afs: Fix afs_xattr_get_yfs() to not try freeing an error valueDavid Howells1-1/+1
afs_xattr_get_yfs() tries to free yacl, which may hold an error value (say if yfs_fs_fetch_opaque_acl() failed and returned an error). Fix this by allocating yacl up front (since it's a fixed-length struct, unlike afs_acl) and passing it in to the RPC function. This also allows the flags to be placed in the object rather than passing them through to the RPC function. Fixes: ae46578b963f ("afs: Get YFS ACLs and information through xattrs") Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-07afs: Implement YFS ACL settingDavid Howells1-0/+1
Implement the setting of YFS ACLs in AFS through the interface of setting the afs.yfs.acl extended attribute on the file. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-07afs: Get YFS ACLs and information through xattrsDavid Howells1-0/+13
The YFS/AuriStor variant of AFS provides more capable ACLs and provides per-volume ACLs and per-file ACLs as well as per-directory ACLs. It also provides some extra information that can be retrieved through four ACLs: (1) afs.yfs.acl The YFS file ACL (not the same format as afs.acl). (2) afs.yfs.vol_acl The YFS volume ACL. (3) afs.yfs.acl_inherited "1" if a file's ACL is inherited from its parent directory, "0" otherwise. (4) afs.yfs.acl_num_cleaned The number of of ACEs removed from the ACL by the server because the PT entries were removed from the PTS database (ie. the subject is no longer known). Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-07afs: implement acl settingJoe Gorse1-0/+1
Implements the setting of ACLs in AFS by means of setting the afs.acl extended attribute on the file. Signed-off-by: Joe Gorse <jhgorse@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-07afs: Get an AFS3 ACL as an xattrDavid Howells1-0/+7
Implement an xattr on AFS files called "afs.acl" that retrieves a file's ACL. It returns the raw AFS3 ACL from the result of calling FS.FetchACL, leaving any interpretation to userspace. Note that whilst YFS servers will respond to FS.FetchACL, this will render a more-advanced YFS ACL down. Use "afs.yfs.acl" instead for that. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-07afs: Log more information for "kAFS: AFS vnode with undefined type\n"David Howells1-1/+2
Log more information when "kAFS: AFS vnode with undefined type\n" is displayed due to a vnode record being retrieved from the server that appears to have a duff file type (usually 0). This prints more information to try and help pin down the problem. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-25afs: Provide mount-time configurable byte-range file locking emulationDavid Howells1-0/+14
Provide byte-range file locking emulation that can be configured at mount time to one of four modes: (1) flock=local. Locking is done locally only and no reference is made to the server. (2) flock=openafs. Byte-range locking is done locally only; whole-file locking is done with reference to the server. Whole-file locks cannot be upgraded unless the client holds an exclusive lock. (3) flock=strict. Byte-range and whole-file locking both require a sufficient whole-file lock on the server. (4) flock=write. As strict, but the client always gets an exclusive whole-file lock on the server. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-25afs: Implement sillyrename for unlink and renameDavid Howells1-0/+10
Implement sillyrename for AFS unlink and rename, using the NFS variant implementation as a basis. Note that the asynchronous file locking extender/releaser has to be notified with a state change to stop it complaining if there's a race between that and the actual file deletion. A tracepoint, afs_silly_rename, is also added to note the silly rename and the cleanup. The afs_edit_dir tracepoint is given some extra reason indicators and the afs_flock_ev tracepoint is given a silly-delete file lock cancellation indicator. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-25afs: Handle lock rpc ops failing on a file that got deletedDavid Howells1-0/+1
Holding a file lock on an AFS file does not prevent it from being deleted on the server, so we need to handle an error resulting from that when we try setting, extending or releasing a lock. Fix this by adding a "deleted" lock state and cancelling the lock extension process for that file and aborting all waiters for the lock. Fixes: 0fafdc9f888b ("afs: Fix file locking") Reported-by: Jonathan Billings <jsbillin@umich.edu> Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-25afs: Calculate lock extend timer from set/extend reply receptionDavid Howells1-0/+2
Record the timestamp on the first reply DATA packet received in response to a set- or extend-lock operation, then use this to calculate the time remaining till the lock expires rather than using whatever time the requesting process wakes up and finishes processing the operation as a base. Signed-off-by: David Howells <dhowells@redhat.com>
2019-04-25afs: Split wait from afs_make_call()David Howells1-5/+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>
2019-04-13afs: Fix in-progess ops to ignore server-level callback invalidationDavid Howells1-3/+1
The in-kernel afs filesystem client counts the number of server-level callback invalidation events (CB.InitCallBackState* RPC operations) that it receives from the server. This is stored in cb_s_break in various structures, including afs_server and afs_vnode. If an inode is examined by afs_validate(), say, the afs_server copy is compared, along with other break counters, to those in afs_vnode, and if one or more of the counters do not match, it is considered that the server's callback promise is broken. At points where this happens, AFS_VNODE_CB_PROMISED is cleared to indicate that the status must be refetched from the server. afs_validate() issues an FS.FetchStatus operation to get updated metadata - and based on the updated data_version may invalidate the pagecache too. However, the break counters are also used to determine whether to note a new callback in the vnode (which would set the AFS_VNODE_CB_PROMISED flag) and whether to cache the permit data included in the YFSFetchStatus record by the server. The problem comes when the server sends us a CB.InitCallBackState op. The first such instance doesn't cause cb_s_break to be incremented, but rather causes AFS_SERVER_FL_NEW to be cleared - but thereafter, say some hours after last use and all the volumes have been automatically unmounted and the server has forgotten about the client[*], this *will* likely cause an increment. [*] There are other circumstances too, such as the server restarting or needing to make space in its callback table. Note that the server won't send us a CB.InitCallBackState op until we talk to it again. So what happens is: (1) A mount for a new volume is attempted, a inode is created for the root vnode and vnode->cb_s_break and AFS_VNODE_CB_PROMISED aren't set immediately, as we don't have a nominated server to talk to yet - and we may iterate through a few to find one. (2) Before the operation happens, afs_fetch_status(), say, notes in the cursor (fc.cb_break) the break counter sum from the vnode, volume and server counters, but the server->cb_s_break is currently 0. (3) We send FS.FetchStatus to the server. The server sends us back CB.InitCallBackState. We increment server->cb_s_break. (4) Our FS.FetchStatus completes. The reply includes a callback record. (5) xdr_decode_AFSCallBack()/xdr_decode_YFSCallBack() check to see whether the callback promise was broken by checking the break counter sum from step (2) against the current sum. This fails because of step (3), so we don't set the callback record and, importantly, don't set AFS_VNODE_CB_PROMISED on the vnode. This does not preclude the syscall from progressing, and we don't loop here rechecking the status, but rather assume it's good enough for one round only and will need to be rechecked next time. (6) afs_validate() it triggered on the vnode, probably called from d_revalidate() checking the parent directory. (7) afs_validate() notes that AFS_VNODE_CB_PROMISED isn't set, so doesn't update vnode->cb_s_break and assumes the vnode to be invalid. (8) afs_validate() needs to calls afs_fetch_status(). Go back to step (2) and repeat, every time the vnode is validated. This primarily affects volume root dir vnodes. Everything subsequent to those inherit an already incremented cb_s_break upon mounting. The issue is that we assume that the callback record and the cached permit information in a reply from the server can't be trusted after getting a server break - but this is wrong since the server makes sure things are done in the right order, holding up our ops if necessary[*]. [*] There is an extremely unlikely scenario where a reply from before the CB.InitCallBackState could get its delivery deferred till after - at which point we think we have a promise when we don't. This, however, requires unlucky mass packet loss to one call. AFS_SERVER_FL_NEW tries to paper over the cracks for the initial mount from a server we've never contacted before, but this should be unnecessary. It's also further insulated from the problem on an initial mount by querying the server first with FS.GetCapabilities, which triggers the CB.InitCallBackState. Fix this by (1) Remove AFS_SERVER_FL_NEW. (2) In afs_calc_vnode_cb_break(), don't include cb_s_break in the calculation. (3) In afs_cb_is_broken(), don't include cb_s_break in the check. Signed-off-by: David Howells <dhowells@redhat.com>
2019-02-28afs: Use fs_context to pass parameters over automountDavid Howells1-1/+0
Alter the AFS automounting code to create and modify an fs_context struct when parameterising a new mount triggered by an AFS mountpoint rather than constructing device name and option strings. Also remove the cell=, vol= and rwpath options as they are then redundant. The reason they existed is because the 'device name' may be derived literally from a mountpoint object in the filesystem, so default cell and parent-type information needed to be passed in by some other method from the automount routines. The vol= option didn't end up being used. Signed-off-by: David Howells <dhowells@redhat.com> cc: Eric W. Biederman <ebiederm@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-28afs: Add fs_context supportDavid Howells1-4/+4
Add fs_context support to the AFS filesystem, converting the parameter parsing to store options there. This will form the basis for namespace propagation over mountpoints within the AFS model, thereby allowing AFS to be used in containers more easily. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-11-29afs: Fix missing net error handlingDavid Howells1-0/+9
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>
2018-10-24afs: Probe multiple fileservers simultaneouslyDavid Howells1-19/+79
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>
2018-10-24afs: Fix callback handlingDavid Howells1-3/+6
In some circumstances, the callback interest pointer is NULL, so in such a case we can't dereference it when checking to see if the callback is broken. This causes an oops in some circumstances. Fix this by replacing the function that worked out the aggregate break counter with one that actually does the comparison, and then make that return true (ie. broken) if there is no callback interest as yet (ie. the pointer is NULL). Fixes: 68251f0a6818 ("afs: Fix whole-volume callback handling") Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Eliminate the address pointer from the address list cursorDavid Howells1-1/+0
Eliminate the address pointer from the address list cursor as it's redundant (ac->addrs[ac->index] can be used to find the same address) and address lists must be replaced rather than being rearranged, so is of limited value. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Allow dumping of server cursor on operation failureDavid Howells1-0/+3
Provide an option to allow the file or volume location server cursor to be dumped if the rotation routine falls off the end without managing to contact a server. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Implement YFS support in the fs clientDavid Howells1-1/+34
Implement support for talking to YFS-variant fileservers in the cache manager and the filesystem client. These implement upgraded services on the same port as their AFS services. YFS fileservers provide expanded capabilities over AFS. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Calc callback expiry in op reply deliveryDavid Howells1-0/+2
Calculate the callback expiration time at the point of operation reply delivery, using the reply time queried from AF_RXRPC on that call as a base. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Add a couple of tracepoints to log I/O errorsDavid Howells1-0/+11
Add a couple of tracepoints to log the production of I/O errors within the AFS filesystem. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Implement VL server rotationDavid Howells1-13/+101
Track VL servers as independent entities rather than lumping all their addresses together into one set and implement server-level rotation by: (1) Add the concept of a VL server list, where each server has its own separate address list. This code is similar to the FS server list. (2) Use the DNS resolver to retrieve a set of servers and their associated addresses, ports, preference and weight ratings. (3) In the case of a legacy DNS resolver or an address list given directly through /proc/net/afs/cells, create a list containing just a dummy server record and attach all the addresses to that. (4) Implement a simple rotation policy, for the moment ignoring the priorities and weights assigned to the servers. (5) Show the address list through /proc/net/afs/<cell>/vlservers. This also displays the source and status of the data as indicated by the upcall. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Improve FS server rotation error handlingDavid Howells1-0/+1
Improve the error handling in FS server rotation by: (1) Cache the latest useful error value for the fs operation as a whole in struct afs_fs_cursor separately from the error cached in the afs_addr_cursor struct. The one in the address cursor gets clobbered occasionally. Copy over the error to the fs operation only when it's something we'd be interested in passing to userspace. (2) Make it so that EDESTADDRREQ is the default that is seen only if no addresses are available to be accessed. (3) When calling utility functions, such as checking a volume status or probing a fileserver, don't let a successful result clobber the cached error in the cursor; instead, stash the result in a temporary variable until it has been assessed. (4) Don't return ETIMEDOUT or ETIME if a better error, such as ENETUNREACH, is already cached. (5) On leaving the rotation loop, turn any remote abort code into a more useful error than ECONNABORTED. Fixes: d2ddc776a458 ("afs: Overhaul volume and server record caching and fileserver rotation") Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Set up the iov_iter before calling afs_extract_data()David Howells1-4/+52
afs_extract_data sets up a temporary iov_iter and passes it to AF_RXRPC each time it is called to describe the remaining buffer to be filled. Instead: (1) Put an iterator in the afs_call struct. (2) Set the iterator for each marshalling stage to load data into the appropriate places. A number of convenience functions are provided to this end (eg. afs_extract_to_buf()). This iterator is then passed to afs_extract_data(). (3) Use the new ITER_DISCARD iterator to discard any excess data provided by FetchData. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Better tracing of protocol errorsDavid Howells1-1/+1
Include the site of detection of AFS protocol errors in trace lines to better be able to determine what went wrong. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+2
Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12afs: Fix cell proc listDavid Howells1-2/+2
Access to the list of cells by /proc/net/afs/cells has a couple of problems: (1) It should be checking against SEQ_START_TOKEN for the keying the header line. (2) It's only holding the RCU read lock, so it can't just walk over the list without following the proper RCU methods. Fix these by using an hlist instead of an ordinary list and using the appropriate accessor functions to follow it with RCU. Since the code that adds a cell to the list must also necessarily change, sort the list on insertion whilst we're at it. Fixes: 989782dcdc91 ("afs: Overhaul cell database management") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-04afs: Do better max capacity handling on address listsDavid Howells1-3/+5
Note the maximum allocated capacity in an afs_addr_list struct and discard addresses that would exceed it in afs_merge_fs_addr{4,6}(). Also, since the current maximum capacity is less than 255, reduce the relevant members to bytes. Signed-off-by: David Howells <dhowells@redhat.com>
2018-08-23fs/afs: use new return type vm_fault_tSouptick Joarder1-1/+2
Use new return type vm_fault_t for fault handler in struct vm_operations_struct. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. See 1c8f422059ae ("mm: change return type to vm_fault_t") for reference. Link: http://lkml.kernel.org/r/20180702152017.GA3780@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-15afs: Optimise callback breaking by not repeating volume lookupDavid Howells1-2/+13
At the moment, afs_break_callbacks calls afs_break_one_callback() for each separate FID it was given, and the latter looks up the volume individually for each one. However, this is inefficient if two or more FIDs have the same vid as we could reuse the volume. This is complicated by cell aliasing whereby we may have multiple cells sharing a volume and can therefore have multiple callback interests for any particular volume ID. At the moment afs_break_one_callback() scans the entire list of volumes we're getting from a server and breaks the appropriate callback in every matching volume, regardless of cell. This scan is done for every FID. Optimise callback breaking by the following means: (1) Sort the FID list by vid so that all FIDs belonging to the same volume are clumped together. This is done through the use of an indirection table as we cannot do an insertion sort on the afs_callback_break array as we decode FIDs into it as we subsequently also have to decode callback info into it that corresponds by array index only. We also don't really want to bubblesort afterwards if we can avoid it. (2) Sort the server->cb_interests array by vid so that all the matching volumes are grouped together. This permits the scan to stop after finding a record that has a higher vid. (3) When breaking FIDs, we try to keep server->cb_break_lock as long as possible, caching the start point in the array for that volume group as long as possible. It might make sense to add another layer in that list and have a refcounted volume ID anchor that has the matching interests attached to it rather than being in the list. This would allow the lock to be dropped without losing the cursor. Signed-off-by: David Howells <dhowells@redhat.com>
2018-06-15afs: Display manually added cells in dynamic root mountDavid Howells1-1/+6
Alter the dynroot mount so that cells created by manipulation of /proc/fs/afs/cells and /proc/fs/afs/rootcell and by specification of a root cell as a module parameter will cause directories for those cells to be created in the dynamic root superblock for the network namespace[*]. To this end: (1) Only one dynamic root superblock is now created per network namespace and this is shared between all attempts to mount it. This makes it easier to find the superblock to modify. (2) When a dynamic root superblock is created, the list of cells is walked and directories created for each cell already defined. (3) When a new cell is added, if a dynamic root superblock exists, a directory is created for it. (4) When a cell is destroyed, the directory is removed. (5) These directories are created by calling lookup_one_len() on the root dir which automatically creates them if they don't exist. [*] Inasmuch as network namespaces are currently supported here. Signed-off-by: David Howells <dhowells@redhat.com>
2018-06-15afs: Handle CONFIG_PROC_FS=nDavid Howells1-0/+8
The AFS filesystem depends at the moment on /proc for configuration and also presents information that way - however, this causes a compilation failure if procfs is disabled. Fix it so that the procfs bits aren't compiled in if procfs is disabled. This means that you can't configure the AFS filesystem directly, but it is still usable provided that an up-to-date keyutils is installed to look up cells by SRV or AFSDB DNS records. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: David Howells <dhowells@redhat.com>
2018-06-02Merge tag 'afs-fixes-20180514' into afs-procAl Viro1-3/+22
backmerge AFS fixes that went into mainline and deal with the conflict in fs/afs/fsclient.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-23afs: Implement network namespacingDavid Howells1-19/+24
Implement network namespacing within AFS, but don't yet let mounts occur outside the init namespace. An additional patch will be required propagate the network namespace across automounts. Signed-off-by: David Howells <dhowells@redhat.com>
2018-05-23afs: Mark afs_net::ws_cell as __rcu and set using rcu functionsDavid Howells1-1/+1
The afs_net::ws_cell member is sometimes used under RCU conditions from within an seq-readlock. It isn't, however, marked __rcu and it isn't set using the proper RCU barrier-imposing functions. Fix this by annotating it with __rcu and using appropriate barriers to make sure accesses are correctly ordered. Without this, the code can produce the following warning: >> fs/afs/proc.c:151:24: sparse: incompatible types in comparison expression (different address spaces) Fixes: f044c8847bb6 ("afs: Lay the groundwork for supporting network namespaces") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: David Howells <dhowells@redhat.com>
2018-05-14afs: Fix whole-volume callback handlingDavid Howells1-0/+15
It's possible for an AFS file server to issue a whole-volume notification that callbacks on all the vnodes in the file have been broken. This is done for R/O and backup volumes (which don't have per-file callbacks) and for things like a volume being taken offline. Fix callback handling to detect whole-volume notifications, to track it across operations and to check it during inode validation. Fixes: c435ee34551e ("afs: Overhaul the callback handling") Signed-off-by: David Howells <dhowells@redhat.com>