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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /fs/lockd/clntlock.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'fs/lockd/clntlock.c')
| -rw-r--r-- | fs/lockd/clntlock.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c new file mode 100644 index 000000000..f797cc99f --- /dev/null +++ b/fs/lockd/clntlock.c @@ -0,0 +1,297 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/fs/lockd/clntlock.c + * + * Lock handling for the client side NLM implementation + * + * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de> + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/nfs_fs.h> +#include <linux/sunrpc/addr.h> +#include <linux/sunrpc/svc.h> +#include <linux/sunrpc/svc_xprt.h> +#include <linux/kthread.h> + +#include "lockd.h" +#include "trace.h" + +#define NLMDBG_FACILITY NLMDBG_CLIENT + +/* + * Local function prototypes + */ +static int reclaimer(void *ptr); + +/* + * The following functions handle blocking and granting from the + * client perspective. + */ + +static LIST_HEAD(nlm_blocked); +static DEFINE_SPINLOCK(nlm_blocked_lock); + +/** + * nlmclnt_init - Set up per-NFS mount point lockd data structures + * @nlm_init: pointer to arguments structure + * + * Returns pointer to an appropriate nlm_host struct, + * or an ERR_PTR value. + */ +struct nlm_host *nlmclnt_init(const struct nlmclnt_initdata *nlm_init) +{ + struct nlm_host *host; + u32 nlm_version = (nlm_init->nfs_version == 2) ? 1 : 4; + int status; + + status = lockd_up(nlm_init->net, nlm_init->cred); + if (status < 0) + return ERR_PTR(status); + + host = nlmclnt_lookup_host(nlm_init->address, nlm_init->addrlen, + nlm_init->protocol, nlm_version, + nlm_init->hostname, nlm_init->noresvport, + nlm_init->net, nlm_init->cred); + if (host == NULL) + goto out_nohost; + if (host->h_rpcclnt == NULL && nlm_bind_host(host) == NULL) + goto out_nobind; + + host->h_nlmclnt_ops = nlm_init->nlmclnt_ops; + return host; +out_nobind: + nlmclnt_release_host(host); +out_nohost: + lockd_down(nlm_init->net); + return ERR_PTR(-ENOLCK); +} +EXPORT_SYMBOL_GPL(nlmclnt_init); + +/** + * nlmclnt_done - Release resources allocated by nlmclnt_init() + * @host: nlm_host structure reserved by nlmclnt_init() + * + */ +void nlmclnt_done(struct nlm_host *host) +{ + struct net *net = host->net; + + nlmclnt_release_host(host); + lockd_down(net); +} +EXPORT_SYMBOL_GPL(nlmclnt_done); + +void nlmclnt_prepare_block(struct nlm_wait *block, struct nlm_host *host, struct file_lock *fl) +{ + block->b_host = host; + block->b_lock = fl; + init_waitqueue_head(&block->b_wait); + block->b_status = nlm_lck_blocked; +} + +struct rpc_clnt *nlmclnt_rpc_clnt(struct nlm_host *host) +{ + return host->h_rpcclnt; +} +EXPORT_SYMBOL_GPL(nlmclnt_rpc_clnt); + +/* + * Queue up a lock for blocking so that the GRANTED request can see it + */ +void nlmclnt_queue_block(struct nlm_wait *block) +{ + spin_lock(&nlm_blocked_lock); + list_add(&block->b_list, &nlm_blocked); + spin_unlock(&nlm_blocked_lock); +} + +/* + * Dequeue the block and return its final status + */ +__be32 nlmclnt_dequeue_block(struct nlm_wait *block) +{ + __be32 status; + + spin_lock(&nlm_blocked_lock); + list_del(&block->b_list); + status = block->b_status; + spin_unlock(&nlm_blocked_lock); + return status; +} + +/* + * Block on a lock + */ +int nlmclnt_wait(struct nlm_wait *block, struct nlm_rqst *req, long timeout) +{ + long ret; + + /* A borken server might ask us to block even if we didn't + * request it. Just say no! + */ + if (block == NULL) + return -EAGAIN; + + /* Go to sleep waiting for GRANT callback. Some servers seem + * to lose callbacks, however, so we're going to poll from + * time to time just to make sure. + * + * For now, the retry frequency is pretty high; normally + * a 1 minute timeout would do. See the comment before + * nlmclnt_lock for an explanation. + */ + ret = wait_event_interruptible_timeout(block->b_wait, + block->b_status != nlm_lck_blocked, + timeout); + if (ret < 0) + return -ERESTARTSYS; + /* Reset the lock status after a server reboot so we resend */ + if (block->b_status == nlm_lck_denied_grace_period) + block->b_status = nlm_lck_blocked; + return 0; +} + +/* + * The server lockd has called us back to tell us the lock was granted + */ +__be32 nlmclnt_grant(const struct sockaddr *addr, const struct lockd_lock *lock) +{ + const struct file_lock *fl = &lock->fl; + const struct nfs_fh *fh = &lock->fh; + struct nlm_wait *block; + __be32 res = nlm_lck_denied; + + /* + * Look up blocked request based on arguments. + * Warning: must not use cookie to match it! + */ + spin_lock(&nlm_blocked_lock); + list_for_each_entry(block, &nlm_blocked, b_list) { + struct file_lock *fl_blocked = block->b_lock; + + if (fl_blocked->fl_start != fl->fl_start) + continue; + if (fl_blocked->fl_end != fl->fl_end) + continue; + /* + * Careful! The NLM server will return the 32-bit "pid" that + * we put on the wire: in this case the lockowner "pid". + */ + if (fl_blocked->fl_u.nfs_fl.owner->pid != lock->svid) + continue; + if (!rpc_cmp_addr(nlm_addr(block->b_host), addr)) + continue; + if (nfs_compare_fh(NFS_FH(file_inode(fl_blocked->c.flc_file)), fh) != 0) + continue; + /* Alright, we found a lock. Set the return status + * and wake up the caller + */ + block->b_status = nlm_granted; + wake_up(&block->b_wait); + res = nlm_granted; + } + spin_unlock(&nlm_blocked_lock); + trace_nlmclnt_grant(lock, addr, svc_addr_len(addr), res); + return res; +} + +/* + * The following procedures deal with the recovery of locks after a + * server crash. + */ + +/* + * Reclaim all locks on server host. We do this by spawning a separate + * reclaimer thread. + */ +void +nlmclnt_recovery(struct nlm_host *host) +{ + struct task_struct *task; + + if (!host->h_reclaiming++) { + nlm_get_host(host); + task = kthread_run(reclaimer, host, "%s-reclaim", host->h_name); + if (IS_ERR(task)) + printk(KERN_ERR "lockd: unable to spawn reclaimer " + "thread. Locks for %s won't be reclaimed! " + "(%ld)\n", host->h_name, PTR_ERR(task)); + } +} + +static int +reclaimer(void *ptr) +{ + struct nlm_host *host = (struct nlm_host *) ptr; + struct nlm_wait *block; + struct nlm_rqst *req; + struct file_lock *fl, *next; + u32 nsmstate; + struct net *net = host->net; + + req = kmalloc_obj(*req); + if (!req) + return 0; + + allow_signal(SIGKILL); + + down_write(&host->h_rwsem); + lockd_up(net, NULL); /* note: this cannot fail as lockd is already running */ + + dprintk("lockd: reclaiming locks for host %s\n", host->h_name); + +restart: + nsmstate = host->h_nsmstate; + + /* Force a portmap getport - the peer's lockd will + * most likely end up on a different port. + */ + host->h_nextrebind = jiffies; + nlm_rebind_host(host); + + /* First, reclaim all locks that have been granted. */ + list_splice_init(&host->h_granted, &host->h_reclaim); + list_for_each_entry_safe(fl, next, &host->h_reclaim, fl_u.nfs_fl.list) { + list_del_init(&fl->fl_u.nfs_fl.list); + + /* + * sending this thread a SIGKILL will result in any unreclaimed + * locks being removed from the h_granted list. This means that + * the kernel will not attempt to reclaim them again if a new + * reclaimer thread is spawned for this host. + */ + if (signalled()) + continue; + if (nlmclnt_reclaim(host, fl, req) != 0) + continue; + list_add_tail(&fl->fl_u.nfs_fl.list, &host->h_granted); + if (host->h_nsmstate != nsmstate) { + /* Argh! The server rebooted again! */ + goto restart; + } + } + + host->h_reclaiming = 0; + up_write(&host->h_rwsem); + dprintk("NLM: done reclaiming locks for host %s\n", host->h_name); + + /* Now, wake up all processes that sleep on a blocked lock */ + spin_lock(&nlm_blocked_lock); + list_for_each_entry(block, &nlm_blocked, b_list) { + if (block->b_host == host) { + block->b_status = nlm_lck_denied_grace_period; + wake_up(&block->b_wait); + } + } + spin_unlock(&nlm_blocked_lock); + + /* Release host handle after use */ + nlmclnt_release_host(host); + lockd_down(net); + kfree(req); + return 0; +} |
