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-rw-r--r--fs/nfs/localio.c1072
1 files changed, 1072 insertions, 0 deletions
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c
new file mode 100644
index 000000000000..f33bfa7b58e6
--- /dev/null
+++ b/fs/nfs/localio.c
@@ -0,0 +1,1072 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * NFS client support for local clients to bypass network stack
+ *
+ * Copyright (C) 2014 Weston Andros Adamson <dros@primarydata.com>
+ * Copyright (C) 2019 Trond Myklebust <trond.myklebust@hammerspace.com>
+ * Copyright (C) 2024 Mike Snitzer <snitzer@hammerspace.com>
+ * Copyright (C) 2024 NeilBrown <neilb@suse.de>
+ */
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/vfs.h>
+#include <linux/file.h>
+#include <linux/inet.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/inetdevice.h>
+#include <net/addrconf.h>
+#include <linux/nfs_common.h>
+#include <linux/nfslocalio.h>
+#include <linux/bvec.h>
+
+#include <linux/nfs.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_xdr.h>
+
+#include "internal.h"
+#include "pnfs.h"
+#include "nfstrace.h"
+
+#define NFSDBG_FACILITY NFSDBG_VFS
+
+#define NFSLOCAL_MAX_IOS 3
+
+struct nfs_local_kiocb {
+ struct kiocb kiocb;
+ struct bio_vec *bvec;
+ struct nfs_pgio_header *hdr;
+ struct work_struct work;
+ void (*aio_complete_work)(struct work_struct *);
+ struct nfsd_file *localio;
+ /* Begin mostly DIO-specific members */
+ size_t end_len;
+ short int end_iter_index;
+ atomic_t n_iters;
+ bool iter_is_dio_aligned[NFSLOCAL_MAX_IOS];
+ struct iov_iter iters[NFSLOCAL_MAX_IOS] ____cacheline_aligned;
+ /* End mostly DIO-specific members */
+};
+
+struct nfs_local_fsync_ctx {
+ struct nfsd_file *localio;
+ struct nfs_commit_data *data;
+ struct work_struct work;
+ struct completion *done;
+};
+
+static bool localio_enabled __read_mostly = true;
+module_param(localio_enabled, bool, 0644);
+
+static inline bool nfs_client_is_local(const struct nfs_client *clp)
+{
+ return !!rcu_access_pointer(clp->cl_uuid.net);
+}
+
+bool nfs_server_is_local(const struct nfs_client *clp)
+{
+ return nfs_client_is_local(clp) && localio_enabled;
+}
+EXPORT_SYMBOL_GPL(nfs_server_is_local);
+
+/*
+ * UUID_IS_LOCAL XDR functions
+ */
+
+static void localio_xdr_enc_uuidargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const u8 *uuid = data;
+
+ encode_opaque_fixed(xdr, uuid, UUID_SIZE);
+}
+
+static int localio_xdr_dec_uuidres(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ void *result)
+{
+ /* void return */
+ return 0;
+}
+
+static const struct rpc_procinfo nfs_localio_procedures[] = {
+ [LOCALIOPROC_UUID_IS_LOCAL] = {
+ .p_proc = LOCALIOPROC_UUID_IS_LOCAL,
+ .p_encode = localio_xdr_enc_uuidargs,
+ .p_decode = localio_xdr_dec_uuidres,
+ .p_arglen = XDR_QUADLEN(UUID_SIZE),
+ .p_replen = 0,
+ .p_statidx = LOCALIOPROC_UUID_IS_LOCAL,
+ .p_name = "UUID_IS_LOCAL",
+ },
+};
+
+static unsigned int nfs_localio_counts[ARRAY_SIZE(nfs_localio_procedures)];
+static const struct rpc_version nfslocalio_version1 = {
+ .number = 1,
+ .nrprocs = ARRAY_SIZE(nfs_localio_procedures),
+ .procs = nfs_localio_procedures,
+ .counts = nfs_localio_counts,
+};
+
+static const struct rpc_version *nfslocalio_version[] = {
+ [1] = &nfslocalio_version1,
+};
+
+extern const struct rpc_program nfslocalio_program;
+static struct rpc_stat nfslocalio_rpcstat = { &nfslocalio_program };
+
+const struct rpc_program nfslocalio_program = {
+ .name = "nfslocalio",
+ .number = NFS_LOCALIO_PROGRAM,
+ .nrvers = ARRAY_SIZE(nfslocalio_version),
+ .version = nfslocalio_version,
+ .stats = &nfslocalio_rpcstat,
+};
+
+/*
+ * nfs_init_localioclient - Initialise an NFS localio client connection
+ */
+static struct rpc_clnt *nfs_init_localioclient(struct nfs_client *clp)
+{
+ struct rpc_clnt *rpcclient_localio;
+
+ rpcclient_localio = rpc_bind_new_program(clp->cl_rpcclient,
+ &nfslocalio_program, 1);
+
+ dprintk_rcu("%s: server (%s) %s NFS LOCALIO.\n",
+ __func__, rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR),
+ (IS_ERR(rpcclient_localio) ? "does not support" : "supports"));
+
+ return rpcclient_localio;
+}
+
+static bool nfs_server_uuid_is_local(struct nfs_client *clp)
+{
+ u8 uuid[UUID_SIZE];
+ struct rpc_message msg = {
+ .rpc_argp = &uuid,
+ };
+ struct rpc_clnt *rpcclient_localio;
+ int status;
+
+ rpcclient_localio = nfs_init_localioclient(clp);
+ if (IS_ERR(rpcclient_localio))
+ return false;
+
+ export_uuid(uuid, &clp->cl_uuid.uuid);
+
+ msg.rpc_proc = &nfs_localio_procedures[LOCALIOPROC_UUID_IS_LOCAL];
+ status = rpc_call_sync(rpcclient_localio, &msg, 0);
+ dprintk("%s: NFS reply UUID_IS_LOCAL: status=%d\n",
+ __func__, status);
+ rpc_shutdown_client(rpcclient_localio);
+
+ /* Server is only local if it initialized required struct members */
+ if (status || !rcu_access_pointer(clp->cl_uuid.net) || !clp->cl_uuid.dom)
+ return false;
+
+ return true;
+}
+
+/*
+ * nfs_local_probe - probe local i/o support for an nfs_server and nfs_client
+ * - called after alloc_client and init_client (so cl_rpcclient exists)
+ * - this function is idempotent, it can be called for old or new clients
+ */
+static void nfs_local_probe(struct nfs_client *clp)
+{
+ /* Disallow localio if disabled via sysfs or AUTH_SYS isn't used */
+ if (!localio_enabled ||
+ clp->cl_rpcclient->cl_auth->au_flavor != RPC_AUTH_UNIX) {
+ nfs_localio_disable_client(clp);
+ return;
+ }
+
+ if (nfs_client_is_local(clp))
+ return;
+
+ if (!nfs_uuid_begin(&clp->cl_uuid))
+ return;
+ if (nfs_server_uuid_is_local(clp))
+ nfs_localio_enable_client(clp);
+ nfs_uuid_end(&clp->cl_uuid);
+}
+
+void nfs_local_probe_async_work(struct work_struct *work)
+{
+ struct nfs_client *clp =
+ container_of(work, struct nfs_client, cl_local_probe_work);
+
+ if (!refcount_inc_not_zero(&clp->cl_count))
+ return;
+ nfs_local_probe(clp);
+ nfs_put_client(clp);
+}
+
+void nfs_local_probe_async(struct nfs_client *clp)
+{
+ queue_work(nfsiod_workqueue, &clp->cl_local_probe_work);
+}
+EXPORT_SYMBOL_GPL(nfs_local_probe_async);
+
+static inline void nfs_local_file_put(struct nfsd_file *localio)
+{
+ /* nfs_to_nfsd_file_put_local() expects an __rcu pointer
+ * but we have a __kernel pointer. It is always safe
+ * to cast a __kernel pointer to an __rcu pointer
+ * because the cast only weakens what is known about the pointer.
+ */
+ struct nfsd_file __rcu *nf = (struct nfsd_file __rcu*) localio;
+
+ nfs_to_nfsd_file_put_local(&nf);
+}
+
+/*
+ * __nfs_local_open_fh - open a local filehandle in terms of nfsd_file.
+ *
+ * Returns a pointer to a struct nfsd_file or ERR_PTR.
+ * Caller must release returned nfsd_file with nfs_to_nfsd_file_put_local().
+ */
+static struct nfsd_file *
+__nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
+ struct nfs_fh *fh, struct nfs_file_localio *nfl,
+ struct nfsd_file __rcu **pnf,
+ const fmode_t mode)
+{
+ int status = 0;
+ struct nfsd_file *localio;
+
+ localio = nfs_open_local_fh(&clp->cl_uuid, clp->cl_rpcclient,
+ cred, fh, nfl, pnf, mode);
+ if (IS_ERR(localio)) {
+ status = PTR_ERR(localio);
+ switch (status) {
+ case -ENOMEM:
+ case -ENXIO:
+ case -ENOENT:
+ /* Revalidate localio */
+ nfs_localio_disable_client(clp);
+ nfs_local_probe(clp);
+ }
+ }
+ trace_nfs_local_open_fh(fh, mode, status);
+ return localio;
+}
+
+/*
+ * nfs_local_open_fh - open a local filehandle in terms of nfsd_file.
+ * First checking if the open nfsd_file is already cached, otherwise
+ * must __nfs_local_open_fh and insert the nfsd_file in nfs_file_localio.
+ *
+ * Returns a pointer to a struct nfsd_file or NULL.
+ */
+struct nfsd_file *
+nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred,
+ struct nfs_fh *fh, struct nfs_file_localio *nfl,
+ const fmode_t mode)
+{
+ struct nfsd_file *nf, __rcu **pnf;
+
+ if (!nfs_server_is_local(clp))
+ return NULL;
+ if (mode & ~(FMODE_READ | FMODE_WRITE))
+ return NULL;
+
+ if (mode & FMODE_WRITE)
+ pnf = &nfl->rw_file;
+ else
+ pnf = &nfl->ro_file;
+
+ nf = __nfs_local_open_fh(clp, cred, fh, nfl, pnf, mode);
+ if (IS_ERR(nf))
+ return NULL;
+ return nf;
+}
+EXPORT_SYMBOL_GPL(nfs_local_open_fh);
+
+static void
+nfs_local_iocb_free(struct nfs_local_kiocb *iocb)
+{
+ kfree(iocb->bvec);
+ kfree(iocb);
+}
+
+static struct nfs_local_kiocb *
+nfs_local_iocb_alloc(struct nfs_pgio_header *hdr,
+ struct file *file, gfp_t flags)
+{
+ struct nfs_local_kiocb *iocb;
+
+ iocb = kzalloc(sizeof(*iocb), flags);
+ if (iocb == NULL)
+ return NULL;
+
+ iocb->bvec = kmalloc_array(hdr->page_array.npages,
+ sizeof(struct bio_vec), flags);
+ if (iocb->bvec == NULL) {
+ kfree(iocb);
+ return NULL;
+ }
+
+ init_sync_kiocb(&iocb->kiocb, file);
+
+ iocb->hdr = hdr;
+ iocb->kiocb.ki_pos = hdr->args.offset;
+ iocb->kiocb.ki_flags &= ~IOCB_APPEND;
+ iocb->kiocb.ki_complete = NULL;
+ iocb->aio_complete_work = NULL;
+
+ iocb->end_iter_index = -1;
+
+ return iocb;
+}
+
+static bool
+nfs_is_local_dio_possible(struct nfs_local_kiocb *iocb, int rw,
+ size_t len, struct nfs_local_dio *local_dio)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+ loff_t offset = hdr->args.offset;
+ u32 nf_dio_mem_align, nf_dio_offset_align, nf_dio_read_offset_align;
+ loff_t start_end, orig_end, middle_end;
+
+ nfs_to->nfsd_file_dio_alignment(iocb->localio, &nf_dio_mem_align,
+ &nf_dio_offset_align, &nf_dio_read_offset_align);
+ if (rw == ITER_DEST)
+ nf_dio_offset_align = nf_dio_read_offset_align;
+
+ if (unlikely(!nf_dio_mem_align || !nf_dio_offset_align))
+ return false;
+ if (unlikely(nf_dio_offset_align > PAGE_SIZE))
+ return false;
+ if (unlikely(len < nf_dio_offset_align))
+ return false;
+
+ local_dio->mem_align = nf_dio_mem_align;
+ local_dio->offset_align = nf_dio_offset_align;
+
+ start_end = round_up(offset, nf_dio_offset_align);
+ orig_end = offset + len;
+ middle_end = round_down(orig_end, nf_dio_offset_align);
+
+ local_dio->middle_offset = start_end;
+ local_dio->end_offset = middle_end;
+
+ local_dio->start_len = start_end - offset;
+ local_dio->middle_len = middle_end - start_end;
+ local_dio->end_len = orig_end - middle_end;
+
+ if (rw == ITER_DEST)
+ trace_nfs_local_dio_read(hdr->inode, offset, len, local_dio);
+ else
+ trace_nfs_local_dio_write(hdr->inode, offset, len, local_dio);
+ return true;
+}
+
+static bool nfs_iov_iter_aligned_bvec(const struct iov_iter *i,
+ unsigned int addr_mask, unsigned int len_mask)
+{
+ const struct bio_vec *bvec = i->bvec;
+ size_t skip = i->iov_offset;
+ size_t size = i->count;
+
+ if (size & len_mask)
+ return false;
+ do {
+ size_t len = bvec->bv_len;
+
+ if (len > size)
+ len = size;
+ if ((unsigned long)(bvec->bv_offset + skip) & addr_mask)
+ return false;
+ bvec++;
+ size -= len;
+ skip = 0;
+ } while (size);
+
+ return true;
+}
+
+static void
+nfs_local_iter_setup(struct iov_iter *iter, int rw, struct bio_vec *bvec,
+ unsigned int nvecs, unsigned long total,
+ size_t start, size_t len)
+{
+ iov_iter_bvec(iter, rw, bvec, nvecs, total);
+ if (start)
+ iov_iter_advance(iter, start);
+ iov_iter_truncate(iter, len);
+}
+
+/*
+ * Setup as many as 3 iov_iter based on extents described by @local_dio.
+ * Returns the number of iov_iter that were setup.
+ */
+static int
+nfs_local_iters_setup_dio(struct nfs_local_kiocb *iocb, int rw,
+ unsigned int nvecs, unsigned long total,
+ struct nfs_local_dio *local_dio)
+{
+ int n_iters = 0;
+ struct iov_iter *iters = iocb->iters;
+
+ /* Setup misaligned start? */
+ if (local_dio->start_len) {
+ nfs_local_iter_setup(&iters[n_iters], rw, iocb->bvec,
+ nvecs, total, 0, local_dio->start_len);
+ ++n_iters;
+ }
+
+ /*
+ * Setup DIO-aligned middle, if there is no misaligned end (below)
+ * then AIO completion is used, see nfs_local_call_{read,write}
+ */
+ nfs_local_iter_setup(&iters[n_iters], rw, iocb->bvec, nvecs,
+ total, local_dio->start_len, local_dio->middle_len);
+
+ iocb->iter_is_dio_aligned[n_iters] =
+ nfs_iov_iter_aligned_bvec(&iters[n_iters],
+ local_dio->mem_align-1, local_dio->offset_align-1);
+
+ if (unlikely(!iocb->iter_is_dio_aligned[n_iters])) {
+ trace_nfs_local_dio_misaligned(iocb->hdr->inode,
+ local_dio->start_len, local_dio->middle_len, local_dio);
+ return 0; /* no DIO-aligned IO possible */
+ }
+ iocb->end_iter_index = n_iters;
+ ++n_iters;
+
+ /* Setup misaligned end? */
+ if (local_dio->end_len) {
+ nfs_local_iter_setup(&iters[n_iters], rw, iocb->bvec,
+ nvecs, total, local_dio->start_len +
+ local_dio->middle_len, local_dio->end_len);
+ iocb->end_iter_index = n_iters;
+ ++n_iters;
+ }
+
+ atomic_set(&iocb->n_iters, n_iters);
+ return n_iters;
+}
+
+static noinline_for_stack void
+nfs_local_iters_init(struct nfs_local_kiocb *iocb, int rw)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+ struct page **pagevec = hdr->page_array.pagevec;
+ unsigned long v, total;
+ unsigned int base;
+ size_t len;
+
+ v = 0;
+ total = hdr->args.count;
+ base = hdr->args.pgbase;
+ while (total && v < hdr->page_array.npages) {
+ len = min_t(size_t, total, PAGE_SIZE - base);
+ bvec_set_page(&iocb->bvec[v], *pagevec, len, base);
+ total -= len;
+ ++pagevec;
+ ++v;
+ base = 0;
+ }
+ len = hdr->args.count - total;
+
+ /*
+ * For each iocb, iocb->n_iters is always at least 1 and we always
+ * end io after first nfs_local_pgio_done call unless misaligned DIO.
+ */
+ atomic_set(&iocb->n_iters, 1);
+
+ if (test_bit(NFS_IOHDR_ODIRECT, &hdr->flags)) {
+ struct nfs_local_dio local_dio;
+
+ if (nfs_is_local_dio_possible(iocb, rw, len, &local_dio) &&
+ nfs_local_iters_setup_dio(iocb, rw, v, len, &local_dio) != 0) {
+ /* Ensure DIO WRITE's IO on stable storage upon completion */
+ if (rw == ITER_SOURCE)
+ iocb->kiocb.ki_flags |= IOCB_DSYNC|IOCB_SYNC;
+ return; /* is DIO-aligned */
+ }
+ }
+
+ /* Use buffered IO */
+ iov_iter_bvec(&iocb->iters[0], rw, iocb->bvec, v, len);
+}
+
+static void
+nfs_local_hdr_release(struct nfs_pgio_header *hdr,
+ const struct rpc_call_ops *call_ops)
+{
+ call_ops->rpc_call_done(&hdr->task, hdr);
+ call_ops->rpc_release(hdr);
+}
+
+static void
+nfs_local_pgio_init(struct nfs_pgio_header *hdr,
+ const struct rpc_call_ops *call_ops)
+{
+ hdr->task.tk_ops = call_ops;
+ if (!hdr->task.tk_start)
+ hdr->task.tk_start = ktime_get();
+}
+
+static bool
+nfs_local_pgio_done(struct nfs_local_kiocb *iocb, long status, bool force)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+
+ /* Must handle partial completions */
+ if (status >= 0) {
+ hdr->res.count += status;
+ /* @hdr was initialized to 0 (zeroed during allocation) */
+ if (hdr->task.tk_status == 0)
+ hdr->res.op_status = NFS4_OK;
+ } else {
+ hdr->res.op_status = nfs_localio_errno_to_nfs4_stat(status);
+ hdr->task.tk_status = status;
+ }
+
+ if (force)
+ return true;
+
+ BUG_ON(atomic_read(&iocb->n_iters) <= 0);
+ return atomic_dec_and_test(&iocb->n_iters);
+}
+
+static void
+nfs_local_iocb_release(struct nfs_local_kiocb *iocb)
+{
+ nfs_local_file_put(iocb->localio);
+ nfs_local_iocb_free(iocb);
+}
+
+static void
+nfs_local_pgio_release(struct nfs_local_kiocb *iocb)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+
+ nfs_local_iocb_release(iocb);
+ nfs_local_hdr_release(hdr, hdr->task.tk_ops);
+}
+
+/*
+ * Complete the I/O from iocb->kiocb.ki_complete()
+ *
+ * Note that this function can be called from a bottom half context,
+ * hence we need to queue the rpc_call_done() etc to a workqueue
+ */
+static inline void nfs_local_pgio_aio_complete(struct nfs_local_kiocb *iocb)
+{
+ INIT_WORK(&iocb->work, iocb->aio_complete_work);
+ queue_work(nfsiod_workqueue, &iocb->work);
+}
+
+static void nfs_local_read_done(struct nfs_local_kiocb *iocb)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+ struct file *filp = iocb->kiocb.ki_filp;
+ long status = hdr->task.tk_status;
+
+ if ((iocb->kiocb.ki_flags & IOCB_DIRECT) && status == -EINVAL) {
+ /* Underlying FS will return -EINVAL if misaligned DIO is attempted. */
+ pr_info_ratelimited("nfs: Unexpected direct I/O read alignment failure\n");
+ }
+
+ /*
+ * Must clear replen otherwise NFSv3 data corruption will occur
+ * if/when switching from LOCALIO back to using normal RPC.
+ */
+ hdr->res.replen = 0;
+
+ /* nfs_readpage_result() handles short read */
+
+ if (hdr->args.offset + hdr->res.count >= i_size_read(file_inode(filp)))
+ hdr->res.eof = true;
+
+ dprintk("%s: read %ld bytes eof %d.\n", __func__,
+ status > 0 ? status : 0, hdr->res.eof);
+}
+
+static inline void nfs_local_read_iocb_done(struct nfs_local_kiocb *iocb)
+{
+ nfs_local_read_done(iocb);
+ nfs_local_pgio_release(iocb);
+}
+
+static void nfs_local_read_aio_complete_work(struct work_struct *work)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(work, struct nfs_local_kiocb, work);
+
+ nfs_local_read_iocb_done(iocb);
+}
+
+static void nfs_local_read_aio_complete(struct kiocb *kiocb, long ret)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(kiocb, struct nfs_local_kiocb, kiocb);
+
+ /* AIO completion of DIO read should always be last to complete */
+ if (unlikely(!nfs_local_pgio_done(iocb, ret, false)))
+ return;
+
+ nfs_local_pgio_aio_complete(iocb); /* Calls nfs_local_read_aio_complete_work */
+}
+
+static void nfs_local_call_read(struct work_struct *work)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(work, struct nfs_local_kiocb, work);
+ struct file *filp = iocb->kiocb.ki_filp;
+ bool force_done = false;
+ ssize_t status;
+ int n_iters;
+
+ n_iters = atomic_read(&iocb->n_iters);
+ for (int i = 0; i < n_iters ; i++) {
+ if (iocb->iter_is_dio_aligned[i]) {
+ iocb->kiocb.ki_flags |= IOCB_DIRECT;
+ /* Only use AIO completion if DIO-aligned segment is last */
+ if (i == iocb->end_iter_index) {
+ iocb->kiocb.ki_complete = nfs_local_read_aio_complete;
+ iocb->aio_complete_work = nfs_local_read_aio_complete_work;
+ }
+ } else
+ iocb->kiocb.ki_flags &= ~IOCB_DIRECT;
+
+ scoped_with_creds(filp->f_cred)
+ status = filp->f_op->read_iter(&iocb->kiocb, &iocb->iters[i]);
+
+ if (status != -EIOCBQUEUED) {
+ if (unlikely(status >= 0 && status < iocb->iters[i].count))
+ force_done = true; /* Partial read */
+ if (nfs_local_pgio_done(iocb, status, force_done)) {
+ nfs_local_read_iocb_done(iocb);
+ break;
+ }
+ }
+ }
+}
+
+static int
+nfs_local_do_read(struct nfs_local_kiocb *iocb,
+ const struct rpc_call_ops *call_ops)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+
+ dprintk("%s: vfs_read count=%u pos=%llu\n",
+ __func__, hdr->args.count, hdr->args.offset);
+
+ nfs_local_pgio_init(hdr, call_ops);
+ hdr->res.eof = false;
+
+ INIT_WORK(&iocb->work, nfs_local_call_read);
+ queue_work(nfslocaliod_workqueue, &iocb->work);
+
+ return 0;
+}
+
+static void
+nfs_copy_boot_verifier(struct nfs_write_verifier *verifier, struct inode *inode)
+{
+ struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+ u32 *verf = (u32 *)verifier->data;
+ unsigned int seq;
+
+ do {
+ seq = read_seqbegin(&clp->cl_boot_lock);
+ verf[0] = (u32)clp->cl_nfssvc_boot.tv_sec;
+ verf[1] = (u32)clp->cl_nfssvc_boot.tv_nsec;
+ } while (read_seqretry(&clp->cl_boot_lock, seq));
+}
+
+static void
+nfs_reset_boot_verifier(struct inode *inode)
+{
+ struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+
+ write_seqlock(&clp->cl_boot_lock);
+ ktime_get_real_ts64(&clp->cl_nfssvc_boot);
+ write_sequnlock(&clp->cl_boot_lock);
+}
+
+static void
+nfs_set_local_verifier(struct inode *inode,
+ struct nfs_writeverf *verf,
+ enum nfs3_stable_how how)
+{
+ nfs_copy_boot_verifier(&verf->verifier, inode);
+ verf->committed = how;
+}
+
+/* Factored out from fs/nfsd/vfs.h:fh_getattr() */
+static int __vfs_getattr(const struct path *p, struct kstat *stat, int version)
+{
+ u32 request_mask = STATX_BASIC_STATS;
+
+ if (version == 4)
+ request_mask |= (STATX_BTIME | STATX_CHANGE_COOKIE);
+ return vfs_getattr(p, stat, request_mask, AT_STATX_SYNC_AS_STAT);
+}
+
+/* Copied from fs/nfsd/nfsfh.c:nfsd4_change_attribute() */
+static u64 __nfsd4_change_attribute(const struct kstat *stat,
+ const struct inode *inode)
+{
+ u64 chattr;
+
+ if (stat->result_mask & STATX_CHANGE_COOKIE) {
+ chattr = stat->change_cookie;
+ if (S_ISREG(inode->i_mode) &&
+ !(stat->attributes & STATX_ATTR_CHANGE_MONOTONIC)) {
+ chattr += (u64)stat->ctime.tv_sec << 30;
+ chattr += stat->ctime.tv_nsec;
+ }
+ } else {
+ chattr = time_to_chattr(&stat->ctime);
+ }
+ return chattr;
+}
+
+static void nfs_local_vfs_getattr(struct nfs_local_kiocb *iocb)
+{
+ struct kstat stat;
+ struct file *filp = iocb->kiocb.ki_filp;
+ struct nfs_pgio_header *hdr = iocb->hdr;
+ struct nfs_fattr *fattr = hdr->res.fattr;
+ int version = NFS_PROTO(hdr->inode)->version;
+
+ if (unlikely(!fattr) || __vfs_getattr(&filp->f_path, &stat, version))
+ return;
+
+ fattr->valid = (NFS_ATTR_FATTR_FILEID |
+ NFS_ATTR_FATTR_CHANGE |
+ NFS_ATTR_FATTR_SIZE |
+ NFS_ATTR_FATTR_ATIME |
+ NFS_ATTR_FATTR_MTIME |
+ NFS_ATTR_FATTR_CTIME |
+ NFS_ATTR_FATTR_SPACE_USED);
+
+ fattr->fileid = stat.ino;
+ fattr->size = stat.size;
+ fattr->atime = stat.atime;
+ fattr->mtime = stat.mtime;
+ fattr->ctime = stat.ctime;
+ if (version == 4) {
+ fattr->change_attr =
+ __nfsd4_change_attribute(&stat, file_inode(filp));
+ } else
+ fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
+ fattr->du.nfs3.used = stat.blocks << 9;
+}
+
+static void nfs_local_write_done(struct nfs_local_kiocb *iocb)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+ long status = hdr->task.tk_status;
+
+ dprintk("%s: wrote %ld bytes.\n", __func__, status > 0 ? status : 0);
+
+ if ((iocb->kiocb.ki_flags & IOCB_DIRECT) && status == -EINVAL) {
+ /* Underlying FS will return -EINVAL if misaligned DIO is attempted. */
+ pr_info_ratelimited("nfs: Unexpected direct I/O write alignment failure\n");
+ }
+
+ /* Handle short writes as if they are ENOSPC */
+ status = hdr->res.count;
+ if (status > 0 && status < hdr->args.count) {
+ hdr->mds_offset += status;
+ hdr->args.offset += status;
+ hdr->args.pgbase += status;
+ hdr->args.count -= status;
+ nfs_set_pgio_error(hdr, -ENOSPC, hdr->args.offset);
+ status = -ENOSPC;
+ /* record -ENOSPC in terms of nfs_local_pgio_done */
+ (void) nfs_local_pgio_done(iocb, status, true);
+ }
+ if (hdr->task.tk_status < 0)
+ nfs_reset_boot_verifier(hdr->inode);
+}
+
+static inline void nfs_local_write_iocb_done(struct nfs_local_kiocb *iocb)
+{
+ nfs_local_write_done(iocb);
+ nfs_local_vfs_getattr(iocb);
+ nfs_local_pgio_release(iocb);
+}
+
+static void nfs_local_write_aio_complete_work(struct work_struct *work)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(work, struct nfs_local_kiocb, work);
+
+ nfs_local_write_iocb_done(iocb);
+}
+
+static void nfs_local_write_aio_complete(struct kiocb *kiocb, long ret)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(kiocb, struct nfs_local_kiocb, kiocb);
+
+ /* AIO completion of DIO write should always be last to complete */
+ if (unlikely(!nfs_local_pgio_done(iocb, ret, false)))
+ return;
+
+ nfs_local_pgio_aio_complete(iocb); /* Calls nfs_local_write_aio_complete_work */
+}
+
+static void nfs_local_call_write(struct work_struct *work)
+{
+ struct nfs_local_kiocb *iocb =
+ container_of(work, struct nfs_local_kiocb, work);
+ struct file *filp = iocb->kiocb.ki_filp;
+ unsigned long old_flags = current->flags;
+ bool force_done = false;
+ ssize_t status;
+ int n_iters;
+
+ current->flags |= PF_LOCAL_THROTTLE | PF_MEMALLOC_NOIO;
+
+ file_start_write(filp);
+ n_iters = atomic_read(&iocb->n_iters);
+ for (int i = 0; i < n_iters ; i++) {
+ if (iocb->iter_is_dio_aligned[i]) {
+ iocb->kiocb.ki_flags |= IOCB_DIRECT;
+ /* Only use AIO completion if DIO-aligned segment is last */
+ if (i == iocb->end_iter_index) {
+ iocb->kiocb.ki_complete = nfs_local_write_aio_complete;
+ iocb->aio_complete_work = nfs_local_write_aio_complete_work;
+ }
+ } else
+ iocb->kiocb.ki_flags &= ~IOCB_DIRECT;
+
+ scoped_with_creds(filp->f_cred)
+ status = filp->f_op->write_iter(&iocb->kiocb, &iocb->iters[i]);
+
+ if (status != -EIOCBQUEUED) {
+ if (unlikely(status >= 0 && status < iocb->iters[i].count))
+ force_done = true; /* Partial write */
+ if (nfs_local_pgio_done(iocb, status, force_done)) {
+ nfs_local_write_iocb_done(iocb);
+ break;
+ }
+ }
+ }
+ file_end_write(filp);
+
+ current->flags = old_flags;
+}
+
+static int
+nfs_local_do_write(struct nfs_local_kiocb *iocb,
+ const struct rpc_call_ops *call_ops)
+{
+ struct nfs_pgio_header *hdr = iocb->hdr;
+
+ dprintk("%s: vfs_write count=%u pos=%llu %s\n",
+ __func__, hdr->args.count, hdr->args.offset,
+ (hdr->args.stable == NFS_UNSTABLE) ? "unstable" : "stable");
+
+ switch (hdr->args.stable) {
+ default:
+ break;
+ case NFS_DATA_SYNC:
+ iocb->kiocb.ki_flags |= IOCB_DSYNC;
+ break;
+ case NFS_FILE_SYNC:
+ iocb->kiocb.ki_flags |= IOCB_DSYNC|IOCB_SYNC;
+ }
+
+ nfs_local_pgio_init(hdr, call_ops);
+
+ nfs_set_local_verifier(hdr->inode, hdr->res.verf, hdr->args.stable);
+
+ INIT_WORK(&iocb->work, nfs_local_call_write);
+ queue_work(nfslocaliod_workqueue, &iocb->work);
+
+ return 0;
+}
+
+static struct nfs_local_kiocb *
+nfs_local_iocb_init(struct nfs_pgio_header *hdr, struct nfsd_file *localio)
+{
+ struct file *file = nfs_to->nfsd_file_file(localio);
+ struct nfs_local_kiocb *iocb;
+ gfp_t gfp_mask;
+ int rw;
+
+ if (hdr->rw_mode & FMODE_READ) {
+ if (!file->f_op->read_iter)
+ return ERR_PTR(-EOPNOTSUPP);
+ gfp_mask = GFP_KERNEL;
+ rw = ITER_DEST;
+ } else {
+ if (!file->f_op->write_iter)
+ return ERR_PTR(-EOPNOTSUPP);
+ gfp_mask = GFP_NOIO;
+ rw = ITER_SOURCE;
+ }
+
+ iocb = nfs_local_iocb_alloc(hdr, file, gfp_mask);
+ if (iocb == NULL)
+ return ERR_PTR(-ENOMEM);
+ iocb->hdr = hdr;
+ iocb->localio = localio;
+
+ nfs_local_iters_init(iocb, rw);
+
+ return iocb;
+}
+
+int nfs_local_doio(struct nfs_client *clp, struct nfsd_file *localio,
+ struct nfs_pgio_header *hdr,
+ const struct rpc_call_ops *call_ops)
+{
+ struct nfs_local_kiocb *iocb;
+ int status = 0;
+
+ if (!hdr->args.count)
+ return 0;
+
+ iocb = nfs_local_iocb_init(hdr, localio);
+ if (IS_ERR(iocb))
+ return PTR_ERR(iocb);
+
+ switch (hdr->rw_mode) {
+ case FMODE_READ:
+ status = nfs_local_do_read(iocb, call_ops);
+ break;
+ case FMODE_WRITE:
+ status = nfs_local_do_write(iocb, call_ops);
+ break;
+ default:
+ dprintk("%s: invalid mode: %d\n", __func__,
+ hdr->rw_mode);
+ status = -EOPNOTSUPP;
+ }
+
+ if (status != 0) {
+ if (status == -EAGAIN)
+ nfs_localio_disable_client(clp);
+ nfs_local_iocb_release(iocb);
+ hdr->task.tk_status = status;
+ nfs_local_hdr_release(hdr, call_ops);
+ }
+ return status;
+}
+
+static void
+nfs_local_init_commit(struct nfs_commit_data *data,
+ const struct rpc_call_ops *call_ops)
+{
+ data->task.tk_ops = call_ops;
+}
+
+static int
+nfs_local_run_commit(struct file *filp, struct nfs_commit_data *data)
+{
+ loff_t start = data->args.offset;
+ loff_t end = LLONG_MAX;
+
+ if (data->args.count > 0) {
+ end = start + data->args.count - 1;
+ if (end < start)
+ end = LLONG_MAX;
+ }
+
+ dprintk("%s: commit %llu - %llu\n", __func__, start, end);
+ return vfs_fsync_range(filp, start, end, 0);
+}
+
+static void
+nfs_local_commit_done(struct nfs_commit_data *data, int status)
+{
+ if (status >= 0) {
+ nfs_set_local_verifier(data->inode,
+ data->res.verf,
+ NFS_FILE_SYNC);
+ data->res.op_status = NFS4_OK;
+ data->task.tk_status = 0;
+ } else {
+ nfs_reset_boot_verifier(data->inode);
+ data->res.op_status = nfs_localio_errno_to_nfs4_stat(status);
+ data->task.tk_status = status;
+ }
+}
+
+static void
+nfs_local_release_commit_data(struct nfsd_file *localio,
+ struct nfs_commit_data *data,
+ const struct rpc_call_ops *call_ops)
+{
+ nfs_local_file_put(localio);
+ call_ops->rpc_call_done(&data->task, data);
+ call_ops->rpc_release(data);
+}
+
+static void
+nfs_local_fsync_ctx_free(struct nfs_local_fsync_ctx *ctx)
+{
+ nfs_local_release_commit_data(ctx->localio, ctx->data,
+ ctx->data->task.tk_ops);
+ kfree(ctx);
+}
+
+static void
+nfs_local_fsync_work(struct work_struct *work)
+{
+ struct nfs_local_fsync_ctx *ctx;
+ int status;
+
+ ctx = container_of(work, struct nfs_local_fsync_ctx, work);
+
+ status = nfs_local_run_commit(nfs_to->nfsd_file_file(ctx->localio),
+ ctx->data);
+ nfs_local_commit_done(ctx->data, status);
+ if (ctx->done != NULL)
+ complete(ctx->done);
+ nfs_local_fsync_ctx_free(ctx);
+}
+
+static struct nfs_local_fsync_ctx *
+nfs_local_fsync_ctx_alloc(struct nfs_commit_data *data,
+ struct nfsd_file *localio, gfp_t flags)
+{
+ struct nfs_local_fsync_ctx *ctx = kmalloc(sizeof(*ctx), flags);
+
+ if (ctx != NULL) {
+ ctx->localio = localio;
+ ctx->data = data;
+ INIT_WORK(&ctx->work, nfs_local_fsync_work);
+ ctx->done = NULL;
+ }
+ return ctx;
+}
+
+int nfs_local_commit(struct nfsd_file *localio,
+ struct nfs_commit_data *data,
+ const struct rpc_call_ops *call_ops, int how)
+{
+ struct nfs_local_fsync_ctx *ctx;
+
+ ctx = nfs_local_fsync_ctx_alloc(data, localio, GFP_KERNEL);
+ if (!ctx) {
+ nfs_local_commit_done(data, -ENOMEM);
+ nfs_local_release_commit_data(localio, data, call_ops);
+ return -ENOMEM;
+ }
+
+ nfs_local_init_commit(data, call_ops);
+
+ if (how & FLUSH_SYNC) {
+ DECLARE_COMPLETION_ONSTACK(done);
+ ctx->done = &done;
+ queue_work(nfsiod_workqueue, &ctx->work);
+ wait_for_completion(&done);
+ } else
+ queue_work(nfsiod_workqueue, &ctx->work);
+
+ return 0;
+}