diff options
Diffstat (limited to 'fs/nfs/localio.c')
-rw-r--r-- | fs/nfs/localio.c | 403 |
1 files changed, 307 insertions, 96 deletions
diff --git a/fs/nfs/localio.c b/fs/nfs/localio.c index 97abf62f109d..b575f0e6c7c8 100644 --- a/fs/nfs/localio.c +++ b/fs/nfs/localio.c @@ -30,6 +30,8 @@ #define NFSDBG_FACILITY NFSDBG_VFS +#define NFSLOCAL_MAX_IOS 3 + struct nfs_local_kiocb { struct kiocb kiocb; struct bio_vec *bvec; @@ -37,6 +39,14 @@ struct nfs_local_kiocb { 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; + short int n_iters; + bool iter_is_dio_aligned[NFSLOCAL_MAX_IOS]; + loff_t offset[NFSLOCAL_MAX_IOS] ____cacheline_aligned; + struct iov_iter iters[NFSLOCAL_MAX_IOS]; + /* End mostly DIO-specific members */ }; struct nfs_local_fsync_ctx { @@ -49,11 +59,6 @@ struct nfs_local_fsync_ctx { static bool localio_enabled __read_mostly = true; module_param(localio_enabled, bool, 0644); -static bool localio_O_DIRECT_semantics __read_mostly = false; -module_param(localio_O_DIRECT_semantics, bool, 0644); -MODULE_PARM_DESC(localio_O_DIRECT_semantics, - "LOCALIO will use O_DIRECT semantics to filesystem."); - static inline bool nfs_client_is_local(const struct nfs_client *clp) { return !!rcu_access_pointer(clp->cl_uuid.net); @@ -231,13 +236,13 @@ __nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred, 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)) { - int status = PTR_ERR(localio); - trace_nfs_local_open_fh(fh, mode, status); + status = PTR_ERR(localio); switch (status) { case -ENOMEM: case -ENXIO: @@ -247,6 +252,7 @@ __nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred, nfs_local_probe(clp); } } + trace_nfs_local_open_fh(fh, mode, status); return localio; } @@ -281,23 +287,6 @@ nfs_local_open_fh(struct nfs_client *clp, const struct cred *cred, } EXPORT_SYMBOL_GPL(nfs_local_open_fh); -static struct bio_vec * -nfs_bvec_alloc_and_import_pagevec(struct page **pagevec, - unsigned int npages, gfp_t flags) -{ - struct bio_vec *bvec, *p; - - bvec = kmalloc_array(npages, sizeof(*bvec), flags); - if (bvec != NULL) { - for (p = bvec; npages > 0; p++, pagevec++, npages--) { - p->bv_page = *pagevec; - p->bv_len = PAGE_SIZE; - p->bv_offset = 0; - } - } - return bvec; -} - static void nfs_local_iocb_free(struct nfs_local_kiocb *iocb) { @@ -311,40 +300,191 @@ nfs_local_iocb_alloc(struct nfs_pgio_header *hdr, { struct nfs_local_kiocb *iocb; - iocb = kmalloc(sizeof(*iocb), flags); + iocb = kzalloc(sizeof(*iocb), flags); if (iocb == NULL) return NULL; - iocb->bvec = nfs_bvec_alloc_and_import_pagevec(hdr->page_array.pagevec, - hdr->page_array.npages, flags); + + iocb->bvec = kmalloc_array(hdr->page_array.npages, + sizeof(struct bio_vec), flags); if (iocb->bvec == NULL) { kfree(iocb); return NULL; } - if (localio_O_DIRECT_semantics && - test_bit(NFS_IOHDR_ODIRECT, &hdr->flags)) { - iocb->kiocb.ki_filp = file; - iocb->kiocb.ki_flags = IOCB_DIRECT; - } else - init_sync_kiocb(&iocb->kiocb, file); + init_sync_kiocb(&iocb->kiocb, file); - iocb->kiocb.ki_pos = hdr->args.offset; iocb->hdr = hdr; iocb->kiocb.ki_flags &= ~IOCB_APPEND; iocb->aio_complete_work = NULL; + iocb->end_iter_index = -1; + return iocb; } -static void -nfs_local_iter_init(struct iov_iter *i, struct nfs_local_kiocb *iocb, int dir) +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; +} + +/* + * 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, size_t len, + struct nfs_local_dio *local_dio) +{ + int n_iters = 0; + struct iov_iter *iters = iocb->iters; + + /* Setup misaligned start? */ + if (local_dio->start_len) { + iov_iter_bvec(&iters[n_iters], rw, iocb->bvec, nvecs, len); + iters[n_iters].count = local_dio->start_len; + iocb->offset[n_iters] = iocb->hdr->args.offset; + iocb->iter_is_dio_aligned[n_iters] = false; + ++n_iters; + } + + /* Setup misaligned end? + * If so, the end is purposely setup to be issued using buffered IO + * before the middle (which will use DIO, if DIO-aligned, with AIO). + * This creates problems if/when the end results in a partial write. + * So must save index and length of end to handle this corner case. + */ + if (local_dio->end_len) { + iov_iter_bvec(&iters[n_iters], rw, iocb->bvec, nvecs, len); + iocb->offset[n_iters] = local_dio->end_offset; + iov_iter_advance(&iters[n_iters], + local_dio->start_len + local_dio->middle_len); + iocb->iter_is_dio_aligned[n_iters] = false; + /* Save index and length of end */ + iocb->end_iter_index = n_iters; + iocb->end_len = local_dio->end_len; + ++n_iters; + } + + /* Setup DIO-aligned middle to be issued last, to allow for + * DIO with AIO completion (see nfs_local_call_{read,write}). + */ + iov_iter_bvec(&iters[n_iters], rw, iocb->bvec, nvecs, len); + if (local_dio->start_len) + iov_iter_advance(&iters[n_iters], local_dio->start_len); + iters[n_iters].count -= local_dio->end_len; + iocb->offset[n_iters] = local_dio->middle_offset; + + 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, + iocb->hdr->args.offset, len, local_dio); + return 0; /* no DIO-aligned IO possible */ + } + ++n_iters; + + 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; + + 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) + return; /* is DIO-aligned */ + } - iov_iter_bvec(i, dir, iocb->bvec, hdr->page_array.npages, - hdr->args.count + hdr->args.pgbase); - if (hdr->args.pgbase != 0) - iov_iter_advance(i, hdr->args.pgbase); + /* Use buffered IO */ + iocb->offset[0] = hdr->args.offset; + iov_iter_bvec(&iocb->iters[0], rw, iocb->bvec, v, len); + iocb->n_iters = 1; } static void @@ -367,10 +507,12 @@ nfs_local_pgio_init(struct nfs_pgio_header *hdr, static void nfs_local_pgio_done(struct nfs_pgio_header *hdr, long status) { + /* Must handle partial completions */ if (status >= 0) { - hdr->res.count = status; - hdr->res.op_status = NFS4_OK; - hdr->task.tk_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; @@ -378,12 +520,18 @@ nfs_local_pgio_done(struct nfs_pgio_header *hdr, long status) } 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_file_put(iocb->localio); - nfs_local_iocb_free(iocb); + nfs_local_iocb_release(iocb); nfs_local_hdr_release(hdr, hdr->task.tk_ops); } @@ -405,7 +553,10 @@ nfs_local_read_done(struct nfs_local_kiocb *iocb, long status) struct nfs_pgio_header *hdr = iocb->hdr; struct file *filp = iocb->kiocb.ki_filp; - nfs_local_pgio_done(hdr, 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 @@ -434,6 +585,7 @@ 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); + nfs_local_pgio_done(iocb->hdr, ret); nfs_local_read_done(iocb, ret); nfs_local_pgio_aio_complete(iocb); /* Calls nfs_local_read_aio_complete_work */ } @@ -444,14 +596,25 @@ static void nfs_local_call_read(struct work_struct *work) container_of(work, struct nfs_local_kiocb, work); struct file *filp = iocb->kiocb.ki_filp; const struct cred *save_cred; - struct iov_iter iter; ssize_t status; save_cred = override_creds(filp->f_cred); - nfs_local_iter_init(&iter, iocb, READ); + for (int i = 0; i < iocb->n_iters ; i++) { + if (iocb->iter_is_dio_aligned[i]) { + iocb->kiocb.ki_flags |= IOCB_DIRECT; + iocb->kiocb.ki_complete = nfs_local_read_aio_complete; + iocb->aio_complete_work = nfs_local_read_aio_complete_work; + } - status = filp->f_op->read_iter(&iocb->kiocb, &iter); + iocb->kiocb.ki_pos = iocb->offset[i]; + status = filp->f_op->read_iter(&iocb->kiocb, &iocb->iters[i]); + if (status != -EIOCBQUEUED) { + nfs_local_pgio_done(iocb->hdr, status); + if (iocb->hdr->task.tk_status) + break; + } + } revert_creds(save_cred); @@ -462,33 +625,17 @@ static void nfs_local_call_read(struct work_struct *work) } static int -nfs_do_local_read(struct nfs_pgio_header *hdr, - struct nfsd_file *localio, +nfs_local_do_read(struct nfs_local_kiocb *iocb, const struct rpc_call_ops *call_ops) { - struct nfs_local_kiocb *iocb; - struct file *file = nfs_to->nfsd_file_file(localio); - - /* Don't support filesystems without read_iter */ - if (!file->f_op->read_iter) - return -EAGAIN; + struct nfs_pgio_header *hdr = iocb->hdr; dprintk("%s: vfs_read count=%u pos=%llu\n", __func__, hdr->args.count, hdr->args.offset); - iocb = nfs_local_iocb_alloc(hdr, file, GFP_KERNEL); - if (iocb == NULL) - return -ENOMEM; - iocb->localio = localio; - nfs_local_pgio_init(hdr, call_ops); hdr->res.eof = false; - if (iocb->kiocb.ki_flags & IOCB_DIRECT) { - iocb->kiocb.ki_complete = nfs_local_read_aio_complete; - iocb->aio_complete_work = nfs_local_read_aio_complete_work; - } - INIT_WORK(&iocb->work, nfs_local_call_read); queue_work(nfslocaliod_workqueue, &iocb->work); @@ -597,7 +744,13 @@ nfs_local_write_done(struct nfs_local_kiocb *iocb, long 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; @@ -605,11 +758,11 @@ nfs_local_write_done(struct nfs_local_kiocb *iocb, long 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 */ + nfs_local_pgio_done(hdr, status); } - if (status < 0) + if (hdr->task.tk_status < 0) nfs_reset_boot_verifier(inode); - - nfs_local_pgio_done(hdr, status); } static void nfs_local_write_aio_complete_work(struct work_struct *work) @@ -626,6 +779,7 @@ 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); + nfs_local_pgio_done(iocb->hdr, ret); nfs_local_write_done(iocb, ret); nfs_local_pgio_aio_complete(iocb); /* Calls nfs_local_write_aio_complete_work */ } @@ -637,16 +791,53 @@ static void nfs_local_call_write(struct work_struct *work) struct file *filp = iocb->kiocb.ki_filp; unsigned long old_flags = current->flags; const struct cred *save_cred; - struct iov_iter iter; ssize_t status; current->flags |= PF_LOCAL_THROTTLE | PF_MEMALLOC_NOIO; save_cred = override_creds(filp->f_cred); - nfs_local_iter_init(&iter, iocb, WRITE); - file_start_write(filp); - status = filp->f_op->write_iter(&iocb->kiocb, &iter); + for (int i = 0; i < iocb->n_iters ; i++) { + if (iocb->iter_is_dio_aligned[i]) { + iocb->kiocb.ki_flags |= IOCB_DIRECT; + iocb->kiocb.ki_complete = nfs_local_write_aio_complete; + iocb->aio_complete_work = nfs_local_write_aio_complete_work; + } +retry: + iocb->kiocb.ki_pos = iocb->offset[i]; + status = filp->f_op->write_iter(&iocb->kiocb, &iocb->iters[i]); + if (status != -EIOCBQUEUED) { + if (unlikely(status >= 0 && status < iocb->iters[i].count)) { + /* partial write */ + if (i == iocb->end_iter_index) { + /* Must not account partial end, otherwise, due + * to end being issued before middle: the partial + * write accounting in nfs_local_write_done() + * would incorrectly advance hdr->args.offset + */ + status = 0; + } else { + /* Partial write at start or buffered middle, + * exit early. + */ + nfs_local_pgio_done(iocb->hdr, status); + break; + } + } else if (unlikely(status == -ENOTBLK && + (iocb->kiocb.ki_flags & IOCB_DIRECT))) { + /* VFS will return -ENOTBLK if DIO WRITE fails to + * invalidate the page cache. Retry using buffered IO. + */ + iocb->kiocb.ki_flags &= ~IOCB_DIRECT; + iocb->kiocb.ki_complete = NULL; + iocb->aio_complete_work = NULL; + goto retry; + } + nfs_local_pgio_done(iocb->hdr, status); + if (iocb->hdr->task.tk_status) + break; + } + } file_end_write(filp); revert_creds(save_cred); @@ -660,26 +851,15 @@ static void nfs_local_call_write(struct work_struct *work) } static int -nfs_do_local_write(struct nfs_pgio_header *hdr, - struct nfsd_file *localio, +nfs_local_do_write(struct nfs_local_kiocb *iocb, const struct rpc_call_ops *call_ops) { - struct nfs_local_kiocb *iocb; - struct file *file = nfs_to->nfsd_file_file(localio); - - /* Don't support filesystems without write_iter */ - if (!file->f_op->write_iter) - return -EAGAIN; + 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"); - iocb = nfs_local_iocb_alloc(hdr, file, GFP_NOIO); - if (iocb == NULL) - return -ENOMEM; - iocb->localio = localio; - switch (hdr->args.stable) { default: break; @@ -694,43 +874,74 @@ nfs_do_local_write(struct nfs_pgio_header *hdr, nfs_set_local_verifier(hdr->inode, hdr->res.verf, hdr->args.stable); - if (iocb->kiocb.ki_flags & IOCB_DIRECT) { - iocb->kiocb.ki_complete = nfs_local_write_aio_complete; - iocb->aio_complete_work = nfs_local_write_aio_complete_work; - } - 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_do_local_read(hdr, localio, call_ops); + status = nfs_local_do_read(iocb, call_ops); break; case FMODE_WRITE: - status = nfs_do_local_write(hdr, localio, call_ops); + status = nfs_local_do_write(iocb, call_ops); break; default: dprintk("%s: invalid mode: %d\n", __func__, hdr->rw_mode); - status = -EINVAL; + status = -EOPNOTSUPP; } if (status != 0) { if (status == -EAGAIN) nfs_localio_disable_client(clp); - nfs_local_file_put(localio); + nfs_local_iocb_release(iocb); hdr->task.tk_status = status; nfs_local_hdr_release(hdr, call_ops); } |