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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: Fix cell DNS lookupDavid Howells1-66/+103
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_cell records to always have a VL server list recordDavid Howells1-8/+11
Fix it such that afs_cell records always have a VL server list record attached, even if it's a dummy one, so that various checks can be removed. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-15afs: Fix missing lock when replacing VL server listDavid Howells1-3/+2
When afs_update_cell() replaces the cell->vl_servers list, it uses RCU protocol so that proc is protected, but doesn't take ->vl_servers_lock to protect afs_start_vl_iteration() (which does actually take a shared lock). Fix this by making afs_update_cell() take an exclusive lock when replacing ->vl_servers. Fixes: 0a5143f2f89c ("afs: Implement VL server rotation") Signed-off-by: David Howells <dhowells@redhat.com>
2019-02-25afs: Fix manually set volume location server listDavid Howells1-0/+1
When a cell with a volume location server list is added manually by echoing the details into /proc/net/afs/cells, a record is added but the flag saying it has been looked up isn't set. This causes the VL server rotation code to wait forever, with the top of /proc/pid/stack looking like: afs_select_vlserver+0x3a6/0x6f3 afs_vl_lookup_vldb+0x4b/0x92 afs_create_volume+0x25/0x1b9 ... with the thread stuck in afs_start_vl_iteration() waiting for AFS_CELL_FL_NO_LOOKUP_YET to be cleared. Fix this by clearing AFS_CELL_FL_NO_LOOKUP_YET when setting up a record if that record's details were supplied manually. Fixes: 0a5143f2f89c ("afs: Implement VL server rotation") Reported-by: Dave Botsch <dwb7@cornell.edu> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-24afs: Fix TTL on VL server and address listsDavid Howells1-4/+22
Currently the TTL on VL server and address lists isn't set in all circumstances and may be set to poor choices in others, since the TTL is derived from the SRV/AFSDB DNS record if and when available. Fix the TTL by limiting the range to a minimum and maximum from the current time. At some point these can be made into sysctl knobs. Further, use the TTL we obtained from the upcall to set the expiry on negative results too; in future a mechanism can be added to force reloading of such data. Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24afs: Implement VL server rotationDavid Howells1-19/+20
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>
2018-10-12afs: Fix cell proc listDavid Howells1-2/+15
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>
2018-06-15afs: Display manually added cells in dynamic root mountDavid Howells1-4/+8
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>
2018-05-23afs: Implement network namespacingDavid Howells1-2/+2
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 Howells1-4/+4
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>
2018-04-09afs: Implement @cell substitution handlingDavid Howells1-0/+2
Implement @cell substitution handling such that if @cell is seen as a name in a dynamic root mount, then the name of the root cell for that network namespace will be substituted for @cell during lookup. The substitution of @cell for the current net namespace is set by writing the cell name to /proc/fs/afs/rootcell. The value can be obtained by reading the file. For example: # mount -t afs none /kafs -o dyn # echo grand.central.org >/proc/fs/afs/rootcell # ls /kafs/@cell archive/ cvs/ doc/ local/ project/ service/ software/ user/ www/ # cat /proc/fs/afs/rootcell grand.central.org Signed-off-by: David Howells <dhowells@redhat.com>
2018-04-09afs: Don't over-increment the cell usage count when pinning itDavid Howells1-2/+2
AFS cells that are added or set as the workstation cell through /proc are pinned against removal by setting the AFS_CELL_FL_NO_GC flag on them and taking a ref. The ref should be only taken if the flag wasn't already set. Fix this by making it conditional. Without this an assertion failure will occur during module removal indicating that the refcount is too elevated. Signed-off-by: David Howells <dhowells@redhat.com>
2018-04-09afs: Fix checker warningsDavid Howells1-3/+3
Fix warnings raised by checker, including: (*) Warnings raised by unequal comparison for the purposes of sorting, where the endianness doesn't matter: fs/afs/addr_list.c:246:21: warning: restricted __be16 degrades to integer fs/afs/addr_list.c:246:30: warning: restricted __be16 degrades to integer fs/afs/addr_list.c:248:21: warning: restricted __be32 degrades to integer fs/afs/addr_list.c:248:49: warning: restricted __be32 degrades to integer fs/afs/addr_list.c:283:21: warning: restricted __be16 degrades to integer fs/afs/addr_list.c:283:30: warning: restricted __be16 degrades to integer (*) afs_set_cb_interest() is not actually used and can be removed. (*) afs_cell_gc_delay() should be provided with a sysctl. (*) afs_cell_destroy() needs to use rcu_access_pointer() to read cell->vl_addrs. (*) afs_init_fs_cursor() should be static. (*) struct afs_vnode::permit_cache needs to be marked __rcu. (*) afs_server_rcu() needs to use rcu_access_pointer(). (*) afs_destroy_server() should use rcu_access_pointer() on server->addresses as the server object is no longer accessible. (*) afs_find_server() casts __be16/__be32 values to int in order to directly compare them for the purpose of finding a match in a list, but is should also annotate the cast with __force to avoid checker warnings. (*) afs_check_permit() accesses vnode->permit_cache outside of the RCU readlock, though it doesn't then access the value; the extraneous access is deleted. False positives: (*) Conditional locking around the code in xdr_decode_AFSFetchStatus. This can be dealt with in a separate patch. fs/afs/fsclient.c:148:9: warning: context imbalance in 'xdr_decode_AFSFetchStatus' - different lock contexts for basic block (*) Incorrect handling of seq-retry lock context balance: fs/afs/inode.c:455:38: warning: context imbalance in 'afs_getattr' - different lock contexts for basic block fs/afs/server.c:52:17: warning: context imbalance in 'afs_find_server' - different lock contexts for basic block fs/afs/server.c:128:17: warning: context imbalance in 'afs_find_server_by_uuid' - different lock contexts for basic block Errors: (*) afs_lookup_cell_rcu() needs to break out of the seq-retry loop, not go round again if it successfully found the workstation cell. (*) Fix UUID decode in afs_deliver_cb_probe_uuid(). (*) afs_cache_permit() has a missing rcu_read_unlock() before one of the jumps to the someone_else_changed_it label. Move the unlock to after the label. (*) afs_vl_get_addrs_u() is using ntohl() rather than htonl() when encoding to XDR. (*) afs_deliver_yfsvl_get_endpoints() is using htonl() rather than ntohl() when decoding from XDR. Signed-off-by: David Howells <dhowells@redhat.com>
2018-04-06fscache: Pass object size in rather than calling back for itDavid Howells1-1/+1
Pass the object size in to fscache_acquire_cookie() and fscache_write_page() rather than the netfs providing a callback by which it can be received. This makes it easier to update the size of the object when a new page is written that extends the object. The current object size is also passed by fscache to the check_aux function, obviating the need to store it in the aux data. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Anna Schumaker <anna.schumaker@netapp.com> Tested-by: Steve Dickson <steved@redhat.com>
2018-04-04fscache: Attach the index key and aux data to the cookieDavid Howells1-1/+3
Attach copies of the index key and auxiliary data to the fscache cookie so that: (1) The callbacks to the netfs for this stuff can be eliminated. This can simplify things in the cache as the information is still available, even after the cache has relinquished the cookie. (2) Simplifies the locking requirements of accessing the information as we don't have to worry about the netfs object going away on us. (3) The cache can do lazy updating of the coherency information on disk. As long as the cache is flushed before reboot/poweroff, there's no need to update the coherency info on disk every time it changes. (4) Cookies can be hashed or put in a tree as the index key is easily available. This allows: (a) Checks for duplicate cookies can be made at the top fscache layer rather than down in the bowels of the cache backend. (b) Caching can be added to a netfs object that has a cookie if the cache is brought online after the netfs object is allocated. A certain amount of space is made in the cookie for inline copies of the data, but if it won't fit there, extra memory will be allocated for it. The downside of this is that live cache operation requires more memory. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Anna Schumaker <anna.schumaker@netapp.com> Tested-by: Steve Dickson <steved@redhat.com>
2018-03-20sched/wait, fs/afs: Convert wait_on_atomic_t() usage to the new ↵Peter Zijlstra1-3/+3
wait_var_event() API The old wait_on_atomic_t() is going to get removed, use the more flexible wait_var_event() API instead. No change in functionality. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-24afs: cell: Remove unnecessary code in afs_lookup_cellGustavo A. R. Silva1-6/+1
Due to recent changes this piece of code is no longer needed. Addresses-Coverity-ID: 1462033 Link: https://lkml.kernel.org/r/4923.1510957307@warthog.procyon.org.uk Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Overhaul volume and server record caching and fileserver rotationDavid Howells1-5/+2
The current code assumes that volumes and servers are per-cell and are never shared, but this is not enforced, and, indeed, public cells do exist that are aliases of each other. Further, an organisation can, say, set up a public cell and a private cell with overlapping, but not identical, sets of servers. The difference is purely in the database attached to the VL servers. The current code will malfunction if it sees a server in two cells as it assumes global address -> server record mappings and that each server is in just one cell. Further, each server may have multiple addresses - and may have addresses of different families (IPv4 and IPv6, say). To this end, the following structural changes are made: (1) Server record management is overhauled: (a) Server records are made independent of cell. The namespace keeps track of them, volume records have lists of them and each vnode has a server on which its callback interest currently resides. (b) The cell record no longer keeps a list of servers known to be in that cell. (c) The server records are now kept in a flat list because there's no single address to sort on. (d) Server records are now keyed by their UUID within the namespace. (e) The addresses for a server are obtained with the VL.GetAddrsU rather than with VL.GetEntryByName, using the server's UUID as a parameter. (f) Cached server records are garbage collected after a period of non-use and are counted out of existence before purging is allowed to complete. This protects the work functions against rmmod. (g) The servers list is now in /proc/fs/afs/servers. (2) Volume record management is overhauled: (a) An RCU-replaceable server list is introduced. This tracks both servers and their coresponding callback interests. (b) The superblock is now keyed on cell record and numeric volume ID. (c) The volume record is now tied to the superblock which mounts it, and is activated when mounted and deactivated when unmounted. This makes it easier to handle the cache cookie without causing a double-use in fscache. (d) The volume record is loaded from the VLDB using VL.GetEntryByNameU to get the server UUID list. (e) The volume name is updated if it is seen to have changed when the volume is updated (the update is keyed on the volume ID). (3) The vlocation record is got rid of and VLDB records are no longer cached. Sufficient information is stored in the volume record, though an update to a volume record is now no longer shared between related volumes (volumes come in bundles of three: R/W, R/O and backup). and the following procedural changes are made: (1) The fileserver cursor introduced previously is now fleshed out and used to iterate over fileservers and their addresses. (2) Volume status is checked during iteration, and the server list is replaced if a change is detected. (3) Server status is checked during iteration, and the address list is replaced if a change is detected. (4) The abort code is saved into the address list cursor and -ECONNABORTED returned in afs_make_call() if a remote abort happened rather than translating the abort into an error message. This allows actions to be taken depending on the abort code more easily. (a) If a VMOVED abort is seen then this is handled by rechecking the volume and restarting the iteration. (b) If a VBUSY, VRESTARTING or VSALVAGING abort is seen then this is handled by sleeping for a short period and retrying and/or trying other servers that might serve that volume. A message is also displayed once until the condition has cleared. (c) If a VOFFLINE abort is seen, then this is handled as VBUSY for the moment. (d) If a VNOVOL abort is seen, the volume is rechecked in the VLDB to see if it has been deleted; if not, the fileserver is probably indicating that the volume couldn't be attached and needs salvaging. (e) If statfs() sees one of these aborts, it does not sleep, but rather returns an error, so as not to block the umount program. (5) The fileserver iteration functions in vnode.c are now merged into their callers and more heavily macroised around the cursor. vnode.c is removed. (6) Operations on a particular vnode are serialised on that vnode because the server will lock that vnode whilst it operates on it, so a second op sent will just have to wait. (7) Fileservers are probed with FS.GetCapabilities before being used. This is where service upgrade will be done. (8) A callback interest on a fileserver is set up before an FS operation is performed and passed through to afs_make_call() so that it can be set on the vnode if the operation returns a callback. The callback interest is passed through to afs_iget() also so that it can be set there too. In general, record updating is done on an as-needed basis when we try to access servers, volumes or vnodes rather than offloading it to work items and special threads. Notes: (1) Pre AFS-3.4 servers are no longer supported, though this can be added back if necessary (AFS-3.4 was released in 1998). (2) VBUSY is retried forever for the moment at intervals of 1s. (3) /proc/fs/afs/<cell>/servers no longer exists. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Add an address list conceptDavid Howells1-111/+58
Add an RCU replaceable address list structure to hold a list of server addresses. The list also holds the To this end: (1) A cell's VL server address list can be loaded directly via insmod or echo to /proc/fs/afs/cells or dynamically from a DNS query for AFSDB or SRV records. (2) Anyone wanting to use a cell's VL server address must wait until the cell record comes online and has tried to obtain some addresses. (3) An FS server's address list, for the moment, has a single entry that is the key to the server list. This will change in the future when a server is instead keyed on its UUID and the VL.GetAddrsU operation is used. (4) An 'address cursor' concept is introduced to handle iteration through the address list. This is passed to the afs_make_call() as, in the future, stuff (such as abort code) that doesn't outlast the call will be returned in it. In the future, we might want to annotate the list with information about how each address fares. We might then want to propagate such annotations over address list replacement. Whilst we're at it, we allow IPv6 addresses to be specified in colon-delimited lists by enclosing them in square brackets. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Overhaul cell database managementDavid Howells1-282/+634
Overhaul the way that the in-kernel AFS client keeps track of cells in the following manner: (1) Cells are now held in an rbtree to make walking them quicker and RCU managed (though this is probably overkill). (2) Cells now have a manager work item that: (A) Looks after fetching and refreshing the VL server list. (B) Manages cell record lifetime, including initialising and destruction. (B) Manages cell record caching whereby threads are kept around for a certain time after last use and then destroyed. (C) Manages the FS-Cache index cookie for a cell. It is not permitted for a cookie to be in use twice, so we have to be careful to not allow a new cell record to exist at the same time as an old record of the same name. (3) Each AFS network namespace is given a manager work item that manages the cells within it, maintaining a single timer to prod cells into updating their DNS records. This uses the reduce_timer() facility to make the timer expire at the soonest timed event that needs happening. (4) When a module is being unloaded, cells and cell managers are now counted out using dec_after_work() to make sure the module text is pinned until after the data structures have been cleaned up. (5) Each cell's VL server list is now protected by a seqlock rather than a semaphore. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Allow IPv6 address specification of VL serversDavid Howells1-10/+21
Allow VL server specifications to be given IPv6 addresses as well as IPv4 addresses, for example as: echo add foo.org 1111:2222:3333:0:4444:5555:6666:7777 >/proc/fs/afs/cells Note that ':' is the expected separator for separating IPv4 addresses, but if a ',' is detected or no '.' is detected in the string, the delimiter is switched to ','. This also works with DNS AFSDB or SRV record strings fetched by upcall from userspace. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Keep and pass sockaddr_rxrpc addresses rather than in_addrDavid Howells1-3/+15
Keep and pass sockaddr_rxrpc addresses around rather than keeping and passing in_addr addresses to allow for the use of IPv6 and non-standard port numbers in future. This also allows the port and service_id fields to be removed from the afs_call struct. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Push the net ns pointer to more placesDavid Howells1-7/+7
Push the network namespace pointer to more places in AFS, including the afs_server structure (which doesn't hold a ref on the netns). In particular, afs_put_cell() now takes requires a net ns parameter so that it can safely alter the netns after decrementing the cell usage count - the cell will be deallocated by a background thread after being cached for a period, which means that it's not safe to access it after reducing its usage count. Signed-off-by: David Howells <dhowells@redhat.com>
2017-11-13afs: Lay the groundwork for supporting network namespacesDavid Howells1-67/+63
Lay the groundwork for supporting network namespaces (netns) to the AFS filesystem by moving various global features to a network-namespace struct (afs_net) and providing an instance of this as a temporary global variable that everything uses via accessor functions for the moment. The following changes have been made: (1) Store the netns in the superblock info. This will be obtained from the mounter's nsproxy on a manual mount and inherited from the parent superblock on an automount. (2) The cell list is made per-netns. It can be viewed through /proc/net/afs/cells and also be modified by writing commands to that file. (3) The local workstation cell is set per-ns in /proc/net/afs/rootcell. This is unset by default. (4) The 'rootcell' module parameter, which sets a cell and VL server list modifies the init net namespace, thereby allowing an AFS root fs to be theoretically used. (5) The volume location lists and the file lock manager are made per-netns. (6) The AF_RXRPC socket and associated I/O bits are made per-ns. The various workqueues remain global for the moment. Changes still to be made: (1) /proc/fs/afs/ should be moved to /proc/net/afs/ and a symlink emplaced from the old name. (2) A per-netns subsys needs to be registered for AFS into which it can store its per-netns data. (3) Rather than the AF_RXRPC socket being opened on module init, it needs to be opened on the creation of a superblock in that netns. (4) The socket needs to be closed when the last superblock using it is destroyed and all outstanding client calls on it have been completed. This prevents a reference loop on the namespace. (5) It is possible that several namespaces will want to use AFS, in which case each one will need its own UDP port. These can either be set through /proc/net/afs/cm_port or the kernel can pick one at random. The init_ns gets 7001 by default. Other issues that need resolving: (1) The DNS keyring needs net-namespacing. (2) Where do upcalls go (eg. DNS request-key upcall)? (3) Need something like open_socket_in_file_ns() syscall so that AFS command line tools attempting to operate on an AFS file/volume have their RPC calls go to the right place. Signed-off-by: David Howells <dhowells@redhat.com>
2013-09-27FS-Cache: Provide the ability to enable/disable cookiesDavid Howells1-1/+1
Provide the ability to enable and disable fscache cookies. A disabled cookie will reject or ignore further requests to: Acquire a child cookie Invalidate and update backing objects Check the consistency of a backing object Allocate storage for backing page Read backing pages Write to backing pages but still allows: Checks/waits on the completion of already in-progress objects Uncaching of pages Relinquishment of cookies Two new operations are provided: (1) Disable a cookie: void fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate); If the cookie is not already disabled, this locks the cookie against other dis/enablement ops, marks the cookie as being disabled, discards or invalidates any backing objects and waits for cessation of activity on any associated object. This is a wrapper around a chunk split out of fscache_relinquish_cookie(), but it reinitialises the cookie such that it can be reenabled. All possible failures are handled internally. The caller should consider calling fscache_uncache_all_inode_pages() afterwards to make sure all page markings are cleared up. (2) Enable a cookie: void fscache_enable_cookie(struct fscache_cookie *cookie, bool (*can_enable)(void *data), void *data) If the cookie is not already enabled, this locks the cookie against other dis/enablement ops, invokes can_enable() and, if the cookie is not an index cookie, will begin the procedure of acquiring backing objects. The optional can_enable() function is passed the data argument and returns a ruling as to whether or not enablement should actually be permitted to begin. All possible failures are handled internally. The cookie will only be marked as enabled if provisional backing objects are allocated. A later patch will introduce these to NFS. Cookie enablement during nfs_open() is then contingent on i_writecount <= 0. can_enable() checks for a race between open(O_RDONLY) and open(O_WRONLY/O_RDWR). This simplifies NFS's cookie handling and allows us to get rid of open(O_RDONLY) accidentally introducing caching to an inode that's open for writing already. One operation has its API modified: (3) Acquire a cookie. struct fscache_cookie *fscache_acquire_cookie( struct fscache_cookie *parent, const struct fscache_cookie_def *def, void *netfs_data, bool enable); This now has an additional argument that indicates whether the requested cookie should be enabled by default. It doesn't need the can_enable() function because the caller must prevent multiple calls for the same netfs object and it doesn't need to take the enablement lock because no one else can get at the cookie before this returns. Signed-off-by: David Howells <dhowells@redhat.com
2011-03-31Fix common misspellingsLucas De Marchi1-1/+1
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2010-08-11AFS: Implement an autocell mount capability [ver #2]wanglei1-14/+38
Implement the ability for the root directory of a mounted AFS filesystem to accept lookups of arbitrary directory names, to interpet the names as the names of cells, to look the cell names up in the DNS for AFSDB records and to mount the root.cell volume of the nominated cell on the pseudo-directory created by lookup. This facility is requested by passing: -o autocell to the mountpoint for which this is desired, usually the /afs mount. To use this facility, a DNS upcall program is required for AFSDB records. This can be obtained from: http://people.redhat.com/~dhowells/afs/dns.afsdb.c It should be compiled with -lresolv and -lkeyutils and installed as, say: /usr/sbin/dns.afsdb Then the following line needs to be added to /sbin/request-key.conf: create dns_resolver afsdb:* * /usr/sbin/dns.afsdb %k This can be tested by mounting AFS, say: insmod dns_resolver.ko insmod af-rxrpc.ko insmod kafs.ko rootcell=grand.central.org mount -t afs "#grand.central.org:root.cell." /afs -o autocell and doing: ls /afs/grand.central.org/ which should show: archive/ cvs/ doc/ local/ project/ service/ software/ user/ www/ if it works. Signed-off-by: Wang Lei <wang840925@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-11DNS: If the DNS server returns an error, allow that to be cached [ver #2]Wang Lei1-0/+4
If the DNS server returns an error, allow that to be cached in the DNS resolver key in lieu of a value. Userspace passes the desired error number as an option in the payload: "#dnserror=<number>" Userspace must map h_errno from the name resolution routines to an appropriate Linux error before passing it up. Something like the following mapping is recommended: [HOST_NOT_FOUND] = ENODATA, [TRY_AGAIN] = EAGAIN, [NO_RECOVERY] = ECONNREFUSED, [NO_DATA] = ENODATA, in lieu of Linux errors specifically for representing name service errors. The filesystem must map these errors appropropriately before passing them to userspace. AFS is made to map ENODATA and EAGAIN to EDESTADDRREQ for the return to userspace; ECONNREFUSED is allowed to stand as is. The error can be seen in /proc/keys as a negative number after the description of the key. Compare, for example, the following key entries: 2f97238c I--Q-- 1 53s 3f010000 0 0 dns_resol afsdb:grand.centrall.org: -61 338bfbbe I--Q-- 1 59m 3f010000 0 0 dns_resol afsdb:grand.central.org: 37 If the error option is supplied in the payload, the main part of the payload is discarded. The key should have an expiry time set by userspace. Signed-off-by: Wang Lei <wang840925@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-08-05DNS: Make AFS go to the DNS for AFSDB records for unknown cellsWang Lei1-10/+30
Add DNS query support for AFS so that it can get the IP addresses of Volume Location servers from the DNS using an AFSDB record. This requires userspace support. /etc/request-key.conf must be configured to invoke a helper for dns_resolver type keys with a subtype of "afsdb:" in the description. Signed-off-by: Wang Lei <wang840925@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2009-04-03FS-Cache: Make kAFS use FS-CacheDavid Howells1-9/+7
The attached patch makes the kAFS filesystem in fs/afs/ use FS-Cache, and through it any attached caches. The kAFS filesystem will use caching automatically if it's available. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2008-04-29afs: use the shorter LIST_HEAD for brevityRobert P. J. Day1-1/+1
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-02afs: add missing up_write() on returnSven Schnelle1-0/+1
If afs_cell_alloc() fails, afs_cells_sem doesn't get unlocked, which leads to a deadlock. Unlock it before returning. Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-28afs: prevent double cell registrationSven Schnelle1-2/+13
kafs doesn't check if the cell already exists - so if you do an echo "add newcell.org 1.2.3.4" >/proc/fs/afs/cells it will try to create this cell again. kobject will also complain about a double registration. To prevent such problems, return -EEXIST in that case. Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17KEYS: Make request_key() and co fundamentally asynchronousDavid Howells1-11/+6
Make request_key() and co fundamentally asynchronous to make it easier for NFS to make use of them. There are now accessor functions that do asynchronous constructions, a wait function to wait for construction to complete, and a completion function for the key type to indicate completion of construction. Note that the construction queue is now gone. Instead, keys under construction are linked in to the appropriate keyring in advance, and that anyone encountering one must wait for it to be complete before they can use it. This is done automatically for userspace. The following auxiliary changes are also made: (1) Key type implementation stuff is split from linux/key.h into linux/key-type.h. (2) AF_RXRPC provides a way to allocate null rxrpc-type keys so that AFS does not need to call key_instantiate_and_link() directly. (3) Adjust the debugging macros so that they're -Wformat checked even if they are disabled, and make it so they can be enabled simply by defining __KDEBUG to be consistent with other code of mine. (3) Documentation. [alan@lxorguk.ukuu.org.uk: keys: missing word in documentation] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17fs/afs/: possible cleanupsAdrian Bunk1-0/+2
This patch contains the following possible cleanups: - make the following needlessly global functions static: - rxrpc.c: afs_send_pages() - vlocation.c: afs_vlocation_queue_for_updates() - write.c: afs_writepages_region() - make the following needlessly global variables static: - mntpt.c: afs_mntpt_expiry_timeout - proc.c: afs_vlocation_states[] - server.c: afs_server_timeout - vlocation.c: afs_vlocation_timeout - vlocation.c: afs_vlocation_update_timeout - #if 0 the following unused function: - cell.c: afs_get_cell_maybe() - #if 0 the following unused variables: - callback.c: afs_vnode_update_timeout - cmservice.c: struct afs_cm_workqueue Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-21Detach sched.h from mm.hAlexey Dobriyan1-0/+1
First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-26[AFS]: Add security support.David Howells1-21/+77
Add security support to the AFS filesystem. Kerberos IV tickets are added as RxRPC keys are added to the session keyring with the klog program. open() and other VFS operations then find this ticket with request_key() and either use it immediately (eg: mkdir, unlink) or attach it to a file descriptor (open). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.David Howells1-274/+70
Make the in-kernel AFS filesystem use AF_RXRPC instead of the old RxRPC code. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26[AFS]: Clean up the AFS sourcesDavid Howells1-33/+18
Clean up the AFS sources. Also remove references to AFS keys. RxRPC keys are used instead. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-14[PATCH] remove many unneeded #includes of sched.hTim Schmielau1-1/+0
After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-06-26[PATCH] fs: use list_move()Akinobu Mita1-2/+1
This patch converts the combination of list_del(A) and list_add(A, B) to list_move(A, B) under fs/. Cc: Ian Kent <raven@themaw.net> Acked-by: Joel Becker <joel.becker@oracle.com> Cc: Neil Brown <neilb@cse.unsw.edu.au> Cc: Hans Reiser <reiserfs-dev@namesys.com> Cc: Urban Widmark <urban@teststation.com> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+569
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!