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619 lines
17 KiB
619 lines
17 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Device operations for the pnfs nfs4 file layout driver. |
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* |
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* Copyright (c) 2014, Primary Data, Inc. All rights reserved. |
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* |
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* Tao Peng <[email protected]> |
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*/ |
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|
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#include <linux/nfs_fs.h> |
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#include <linux/vmalloc.h> |
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#include <linux/module.h> |
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#include <linux/sunrpc/addr.h> |
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|
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#include "../internal.h" |
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#include "../nfs4session.h" |
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#include "flexfilelayout.h" |
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|
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#define NFSDBG_FACILITY NFSDBG_PNFS_LD |
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|
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static unsigned int dataserver_timeo = NFS_DEF_TCP_TIMEO; |
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static unsigned int dataserver_retrans; |
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|
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static bool ff_layout_has_available_ds(struct pnfs_layout_segment *lseg); |
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|
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void nfs4_ff_layout_put_deviceid(struct nfs4_ff_layout_ds *mirror_ds) |
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{ |
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if (!IS_ERR_OR_NULL(mirror_ds)) |
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nfs4_put_deviceid_node(&mirror_ds->id_node); |
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} |
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|
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void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds) |
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{ |
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nfs4_print_deviceid(&mirror_ds->id_node.deviceid); |
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nfs4_pnfs_ds_put(mirror_ds->ds); |
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kfree(mirror_ds->ds_versions); |
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kfree_rcu(mirror_ds, id_node.rcu); |
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} |
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|
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/* Decode opaque device data and construct new_ds using it */ |
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struct nfs4_ff_layout_ds * |
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nfs4_ff_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev, |
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gfp_t gfp_flags) |
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{ |
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struct xdr_stream stream; |
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struct xdr_buf buf; |
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struct page *scratch; |
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struct list_head dsaddrs; |
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struct nfs4_pnfs_ds_addr *da; |
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struct nfs4_ff_layout_ds *new_ds = NULL; |
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struct nfs4_ff_ds_version *ds_versions = NULL; |
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u32 mp_count; |
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u32 version_count; |
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__be32 *p; |
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int i, ret = -ENOMEM; |
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|
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/* set up xdr stream */ |
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scratch = alloc_page(gfp_flags); |
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if (!scratch) |
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goto out_err; |
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|
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new_ds = kzalloc(sizeof(struct nfs4_ff_layout_ds), gfp_flags); |
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if (!new_ds) |
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goto out_scratch; |
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|
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nfs4_init_deviceid_node(&new_ds->id_node, |
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server, |
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&pdev->dev_id); |
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INIT_LIST_HEAD(&dsaddrs); |
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|
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xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen); |
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xdr_set_scratch_page(&stream, scratch); |
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|
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/* multipath count */ |
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p = xdr_inline_decode(&stream, 4); |
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if (unlikely(!p)) |
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goto out_err_drain_dsaddrs; |
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mp_count = be32_to_cpup(p); |
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dprintk("%s: multipath ds count %d\n", __func__, mp_count); |
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|
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for (i = 0; i < mp_count; i++) { |
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/* multipath ds */ |
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da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net, |
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&stream, gfp_flags); |
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if (da) |
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list_add_tail(&da->da_node, &dsaddrs); |
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} |
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if (list_empty(&dsaddrs)) { |
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dprintk("%s: no suitable DS addresses found\n", |
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__func__); |
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ret = -ENOMEDIUM; |
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goto out_err_drain_dsaddrs; |
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} |
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|
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/* version count */ |
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p = xdr_inline_decode(&stream, 4); |
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if (unlikely(!p)) |
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goto out_err_drain_dsaddrs; |
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version_count = be32_to_cpup(p); |
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dprintk("%s: version count %d\n", __func__, version_count); |
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|
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ds_versions = kcalloc(version_count, |
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sizeof(struct nfs4_ff_ds_version), |
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gfp_flags); |
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if (!ds_versions) |
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goto out_scratch; |
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|
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for (i = 0; i < version_count; i++) { |
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/* 20 = version(4) + minor_version(4) + rsize(4) + wsize(4) + |
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* tightly_coupled(4) */ |
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p = xdr_inline_decode(&stream, 20); |
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if (unlikely(!p)) |
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goto out_err_drain_dsaddrs; |
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ds_versions[i].version = be32_to_cpup(p++); |
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ds_versions[i].minor_version = be32_to_cpup(p++); |
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ds_versions[i].rsize = nfs_block_size(be32_to_cpup(p++), NULL); |
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ds_versions[i].wsize = nfs_block_size(be32_to_cpup(p++), NULL); |
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ds_versions[i].tightly_coupled = be32_to_cpup(p); |
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|
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if (ds_versions[i].rsize > NFS_MAX_FILE_IO_SIZE) |
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ds_versions[i].rsize = NFS_MAX_FILE_IO_SIZE; |
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if (ds_versions[i].wsize > NFS_MAX_FILE_IO_SIZE) |
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ds_versions[i].wsize = NFS_MAX_FILE_IO_SIZE; |
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|
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/* |
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* check for valid major/minor combination. |
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* currently we support dataserver which talk: |
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* v3, v4.0, v4.1, v4.2 |
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*/ |
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if (!((ds_versions[i].version == 3 && ds_versions[i].minor_version == 0) || |
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(ds_versions[i].version == 4 && ds_versions[i].minor_version < 3))) { |
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dprintk("%s: [%d] unsupported ds version %d-%d\n", __func__, |
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i, ds_versions[i].version, |
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ds_versions[i].minor_version); |
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ret = -EPROTONOSUPPORT; |
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goto out_err_drain_dsaddrs; |
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} |
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|
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dprintk("%s: [%d] vers %u minor_ver %u rsize %u wsize %u coupled %d\n", |
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__func__, i, ds_versions[i].version, |
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ds_versions[i].minor_version, |
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ds_versions[i].rsize, |
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ds_versions[i].wsize, |
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ds_versions[i].tightly_coupled); |
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} |
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|
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new_ds->ds_versions = ds_versions; |
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new_ds->ds_versions_cnt = version_count; |
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|
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new_ds->ds = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags); |
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if (!new_ds->ds) |
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goto out_err_drain_dsaddrs; |
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|
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/* If DS was already in cache, free ds addrs */ |
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while (!list_empty(&dsaddrs)) { |
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da = list_first_entry(&dsaddrs, |
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struct nfs4_pnfs_ds_addr, |
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da_node); |
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list_del_init(&da->da_node); |
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kfree(da->da_remotestr); |
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kfree(da); |
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} |
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|
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__free_page(scratch); |
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return new_ds; |
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|
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out_err_drain_dsaddrs: |
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while (!list_empty(&dsaddrs)) { |
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da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr, |
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da_node); |
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list_del_init(&da->da_node); |
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kfree(da->da_remotestr); |
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kfree(da); |
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} |
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|
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kfree(ds_versions); |
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out_scratch: |
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__free_page(scratch); |
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out_err: |
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kfree(new_ds); |
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|
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dprintk("%s ERROR: returning %d\n", __func__, ret); |
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return NULL; |
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} |
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|
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static void extend_ds_error(struct nfs4_ff_layout_ds_err *err, |
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u64 offset, u64 length) |
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{ |
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u64 end; |
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|
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end = max_t(u64, pnfs_end_offset(err->offset, err->length), |
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pnfs_end_offset(offset, length)); |
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err->offset = min_t(u64, err->offset, offset); |
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err->length = end - err->offset; |
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} |
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|
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static int |
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ff_ds_error_match(const struct nfs4_ff_layout_ds_err *e1, |
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const struct nfs4_ff_layout_ds_err *e2) |
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{ |
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int ret; |
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|
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if (e1->opnum != e2->opnum) |
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return e1->opnum < e2->opnum ? -1 : 1; |
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if (e1->status != e2->status) |
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return e1->status < e2->status ? -1 : 1; |
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ret = memcmp(e1->stateid.data, e2->stateid.data, |
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sizeof(e1->stateid.data)); |
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if (ret != 0) |
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return ret; |
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ret = memcmp(&e1->deviceid, &e2->deviceid, sizeof(e1->deviceid)); |
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if (ret != 0) |
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return ret; |
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if (pnfs_end_offset(e1->offset, e1->length) < e2->offset) |
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return -1; |
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if (e1->offset > pnfs_end_offset(e2->offset, e2->length)) |
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return 1; |
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/* If ranges overlap or are contiguous, they are the same */ |
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return 0; |
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} |
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|
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static void |
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ff_layout_add_ds_error_locked(struct nfs4_flexfile_layout *flo, |
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struct nfs4_ff_layout_ds_err *dserr) |
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{ |
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struct nfs4_ff_layout_ds_err *err, *tmp; |
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struct list_head *head = &flo->error_list; |
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int match; |
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|
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/* Do insertion sort w/ merges */ |
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list_for_each_entry_safe(err, tmp, &flo->error_list, list) { |
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match = ff_ds_error_match(err, dserr); |
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if (match < 0) |
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continue; |
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if (match > 0) { |
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/* Add entry "dserr" _before_ entry "err" */ |
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head = &err->list; |
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break; |
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} |
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/* Entries match, so merge "err" into "dserr" */ |
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extend_ds_error(dserr, err->offset, err->length); |
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list_replace(&err->list, &dserr->list); |
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kfree(err); |
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return; |
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} |
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|
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list_add_tail(&dserr->list, head); |
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} |
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|
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int ff_layout_track_ds_error(struct nfs4_flexfile_layout *flo, |
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struct nfs4_ff_layout_mirror *mirror, u64 offset, |
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u64 length, int status, enum nfs_opnum4 opnum, |
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gfp_t gfp_flags) |
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{ |
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struct nfs4_ff_layout_ds_err *dserr; |
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|
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if (status == 0) |
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return 0; |
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|
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if (IS_ERR_OR_NULL(mirror->mirror_ds)) |
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return -EINVAL; |
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|
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dserr = kmalloc(sizeof(*dserr), gfp_flags); |
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if (!dserr) |
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return -ENOMEM; |
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|
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INIT_LIST_HEAD(&dserr->list); |
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dserr->offset = offset; |
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dserr->length = length; |
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dserr->status = status; |
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dserr->opnum = opnum; |
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nfs4_stateid_copy(&dserr->stateid, &mirror->stateid); |
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memcpy(&dserr->deviceid, &mirror->mirror_ds->id_node.deviceid, |
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NFS4_DEVICEID4_SIZE); |
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|
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spin_lock(&flo->generic_hdr.plh_inode->i_lock); |
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ff_layout_add_ds_error_locked(flo, dserr); |
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spin_unlock(&flo->generic_hdr.plh_inode->i_lock); |
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return 0; |
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} |
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|
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static const struct cred * |
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ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode) |
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{ |
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const struct cred *cred, __rcu **pcred; |
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|
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if (iomode == IOMODE_READ) |
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pcred = &mirror->ro_cred; |
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else |
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pcred = &mirror->rw_cred; |
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|
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rcu_read_lock(); |
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do { |
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cred = rcu_dereference(*pcred); |
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if (!cred) |
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break; |
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|
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cred = get_cred_rcu(cred); |
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} while(!cred); |
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rcu_read_unlock(); |
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return cred; |
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} |
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|
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struct nfs_fh * |
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nfs4_ff_layout_select_ds_fh(struct nfs4_ff_layout_mirror *mirror) |
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{ |
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/* FIXME: For now assume there is only 1 version available for the DS */ |
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return &mirror->fh_versions[0]; |
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} |
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|
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void |
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nfs4_ff_layout_select_ds_stateid(const struct nfs4_ff_layout_mirror *mirror, |
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nfs4_stateid *stateid) |
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{ |
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if (nfs4_ff_layout_ds_version(mirror) == 4) |
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nfs4_stateid_copy(stateid, &mirror->stateid); |
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} |
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|
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static bool |
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ff_layout_init_mirror_ds(struct pnfs_layout_hdr *lo, |
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struct nfs4_ff_layout_mirror *mirror) |
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{ |
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if (mirror == NULL) |
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goto outerr; |
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if (mirror->mirror_ds == NULL) { |
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struct nfs4_deviceid_node *node; |
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struct nfs4_ff_layout_ds *mirror_ds = ERR_PTR(-ENODEV); |
|
|
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node = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), |
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&mirror->devid, lo->plh_lc_cred, |
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GFP_KERNEL); |
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if (node) |
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mirror_ds = FF_LAYOUT_MIRROR_DS(node); |
|
|
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/* check for race with another call to this function */ |
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if (cmpxchg(&mirror->mirror_ds, NULL, mirror_ds) && |
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mirror_ds != ERR_PTR(-ENODEV)) |
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nfs4_put_deviceid_node(node); |
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} |
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|
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if (IS_ERR(mirror->mirror_ds)) |
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goto outerr; |
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|
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return true; |
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outerr: |
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return false; |
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} |
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|
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/** |
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* nfs4_ff_layout_prepare_ds - prepare a DS connection for an RPC call |
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* @lseg: the layout segment we're operating on |
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* @mirror: layout mirror describing the DS to use |
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* @fail_return: return layout on connect failure? |
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* |
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* Try to prepare a DS connection to accept an RPC call. This involves |
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* selecting a mirror to use and connecting the client to it if it's not |
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* already connected. |
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* |
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* Since we only need a single functioning mirror to satisfy a read, we don't |
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* want to return the layout if there is one. For writes though, any down |
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* mirror should result in a LAYOUTRETURN. @fail_return is how we distinguish |
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* between the two cases. |
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* |
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* Returns a pointer to a connected DS object on success or NULL on failure. |
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*/ |
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struct nfs4_pnfs_ds * |
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nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, |
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struct nfs4_ff_layout_mirror *mirror, |
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bool fail_return) |
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{ |
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struct nfs4_pnfs_ds *ds = NULL; |
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struct inode *ino = lseg->pls_layout->plh_inode; |
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struct nfs_server *s = NFS_SERVER(ino); |
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unsigned int max_payload; |
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int status; |
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|
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if (!ff_layout_init_mirror_ds(lseg->pls_layout, mirror)) |
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goto noconnect; |
|
|
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ds = mirror->mirror_ds->ds; |
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/* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */ |
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smp_rmb(); |
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if (ds->ds_clp) |
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goto out; |
|
|
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/* FIXME: For now we assume the server sent only one version of NFS |
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* to use for the DS. |
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*/ |
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status = nfs4_pnfs_ds_connect(s, ds, &mirror->mirror_ds->id_node, |
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dataserver_timeo, dataserver_retrans, |
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mirror->mirror_ds->ds_versions[0].version, |
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mirror->mirror_ds->ds_versions[0].minor_version); |
|
|
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/* connect success, check rsize/wsize limit */ |
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if (!status) { |
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max_payload = |
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nfs_block_size(rpc_max_payload(ds->ds_clp->cl_rpcclient), |
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NULL); |
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if (mirror->mirror_ds->ds_versions[0].rsize > max_payload) |
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mirror->mirror_ds->ds_versions[0].rsize = max_payload; |
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if (mirror->mirror_ds->ds_versions[0].wsize > max_payload) |
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mirror->mirror_ds->ds_versions[0].wsize = max_payload; |
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goto out; |
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} |
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noconnect: |
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ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout), |
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mirror, lseg->pls_range.offset, |
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lseg->pls_range.length, NFS4ERR_NXIO, |
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OP_ILLEGAL, GFP_NOIO); |
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ff_layout_send_layouterror(lseg); |
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if (fail_return || !ff_layout_has_available_ds(lseg)) |
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pnfs_error_mark_layout_for_return(ino, lseg); |
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ds = NULL; |
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out: |
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return ds; |
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} |
|
|
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const struct cred * |
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ff_layout_get_ds_cred(struct nfs4_ff_layout_mirror *mirror, |
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const struct pnfs_layout_range *range, |
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const struct cred *mdscred) |
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{ |
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const struct cred *cred; |
|
|
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if (mirror && !mirror->mirror_ds->ds_versions[0].tightly_coupled) { |
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cred = ff_layout_get_mirror_cred(mirror, range->iomode); |
|
if (!cred) |
|
cred = get_cred(mdscred); |
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} else { |
|
cred = get_cred(mdscred); |
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} |
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return cred; |
|
} |
|
|
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/** |
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* nfs4_ff_find_or_create_ds_client - Find or create a DS rpc client |
|
* @mirror: pointer to the mirror |
|
* @ds_clp: nfs_client for the DS |
|
* @inode: pointer to inode |
|
* |
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* Find or create a DS rpc client with th MDS server rpc client auth flavor |
|
* in the nfs_client cl_ds_clients list. |
|
*/ |
|
struct rpc_clnt * |
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nfs4_ff_find_or_create_ds_client(struct nfs4_ff_layout_mirror *mirror, |
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struct nfs_client *ds_clp, struct inode *inode) |
|
{ |
|
switch (mirror->mirror_ds->ds_versions[0].version) { |
|
case 3: |
|
/* For NFSv3 DS, flavor is set when creating DS connections */ |
|
return ds_clp->cl_rpcclient; |
|
case 4: |
|
return nfs4_find_or_create_ds_client(ds_clp, inode); |
|
default: |
|
BUG(); |
|
} |
|
} |
|
|
|
void ff_layout_free_ds_ioerr(struct list_head *head) |
|
{ |
|
struct nfs4_ff_layout_ds_err *err; |
|
|
|
while (!list_empty(head)) { |
|
err = list_first_entry(head, |
|
struct nfs4_ff_layout_ds_err, |
|
list); |
|
list_del(&err->list); |
|
kfree(err); |
|
} |
|
} |
|
|
|
/* called with inode i_lock held */ |
|
int ff_layout_encode_ds_ioerr(struct xdr_stream *xdr, const struct list_head *head) |
|
{ |
|
struct nfs4_ff_layout_ds_err *err; |
|
__be32 *p; |
|
|
|
list_for_each_entry(err, head, list) { |
|
/* offset(8) + length(8) + stateid(NFS4_STATEID_SIZE) |
|
* + array length + deviceid(NFS4_DEVICEID4_SIZE) |
|
* + status(4) + opnum(4) |
|
*/ |
|
p = xdr_reserve_space(xdr, |
|
28 + NFS4_STATEID_SIZE + NFS4_DEVICEID4_SIZE); |
|
if (unlikely(!p)) |
|
return -ENOBUFS; |
|
p = xdr_encode_hyper(p, err->offset); |
|
p = xdr_encode_hyper(p, err->length); |
|
p = xdr_encode_opaque_fixed(p, &err->stateid, |
|
NFS4_STATEID_SIZE); |
|
/* Encode 1 error */ |
|
*p++ = cpu_to_be32(1); |
|
p = xdr_encode_opaque_fixed(p, &err->deviceid, |
|
NFS4_DEVICEID4_SIZE); |
|
*p++ = cpu_to_be32(err->status); |
|
*p++ = cpu_to_be32(err->opnum); |
|
dprintk("%s: offset %llu length %llu status %d op %d\n", |
|
__func__, err->offset, err->length, err->status, |
|
err->opnum); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static |
|
unsigned int do_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo, |
|
const struct pnfs_layout_range *range, |
|
struct list_head *head, |
|
unsigned int maxnum) |
|
{ |
|
struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo); |
|
struct inode *inode = lo->plh_inode; |
|
struct nfs4_ff_layout_ds_err *err, *n; |
|
unsigned int ret = 0; |
|
|
|
spin_lock(&inode->i_lock); |
|
list_for_each_entry_safe(err, n, &flo->error_list, list) { |
|
if (!pnfs_is_range_intersecting(err->offset, |
|
pnfs_end_offset(err->offset, err->length), |
|
range->offset, |
|
pnfs_end_offset(range->offset, range->length))) |
|
continue; |
|
if (!maxnum) |
|
break; |
|
list_move(&err->list, head); |
|
maxnum--; |
|
ret++; |
|
} |
|
spin_unlock(&inode->i_lock); |
|
return ret; |
|
} |
|
|
|
unsigned int ff_layout_fetch_ds_ioerr(struct pnfs_layout_hdr *lo, |
|
const struct pnfs_layout_range *range, |
|
struct list_head *head, |
|
unsigned int maxnum) |
|
{ |
|
unsigned int ret; |
|
|
|
ret = do_layout_fetch_ds_ioerr(lo, range, head, maxnum); |
|
/* If we're over the max, discard all remaining entries */ |
|
if (ret == maxnum) { |
|
LIST_HEAD(discard); |
|
do_layout_fetch_ds_ioerr(lo, range, &discard, -1); |
|
ff_layout_free_ds_ioerr(&discard); |
|
} |
|
return ret; |
|
} |
|
|
|
static bool ff_read_layout_has_available_ds(struct pnfs_layout_segment *lseg) |
|
{ |
|
struct nfs4_ff_layout_mirror *mirror; |
|
struct nfs4_deviceid_node *devid; |
|
u32 idx; |
|
|
|
for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) { |
|
mirror = FF_LAYOUT_COMP(lseg, idx); |
|
if (mirror) { |
|
if (!mirror->mirror_ds) |
|
return true; |
|
if (IS_ERR(mirror->mirror_ds)) |
|
continue; |
|
devid = &mirror->mirror_ds->id_node; |
|
if (!nfs4_test_deviceid_unavailable(devid)) |
|
return true; |
|
} |
|
} |
|
|
|
return false; |
|
} |
|
|
|
static bool ff_rw_layout_has_available_ds(struct pnfs_layout_segment *lseg) |
|
{ |
|
struct nfs4_ff_layout_mirror *mirror; |
|
struct nfs4_deviceid_node *devid; |
|
u32 idx; |
|
|
|
for (idx = 0; idx < FF_LAYOUT_MIRROR_COUNT(lseg); idx++) { |
|
mirror = FF_LAYOUT_COMP(lseg, idx); |
|
if (!mirror || IS_ERR(mirror->mirror_ds)) |
|
return false; |
|
if (!mirror->mirror_ds) |
|
continue; |
|
devid = &mirror->mirror_ds->id_node; |
|
if (nfs4_test_deviceid_unavailable(devid)) |
|
return false; |
|
} |
|
|
|
return FF_LAYOUT_MIRROR_COUNT(lseg) != 0; |
|
} |
|
|
|
static bool ff_layout_has_available_ds(struct pnfs_layout_segment *lseg) |
|
{ |
|
if (lseg->pls_range.iomode == IOMODE_READ) |
|
return ff_read_layout_has_available_ds(lseg); |
|
/* Note: RW layout needs all mirrors available */ |
|
return ff_rw_layout_has_available_ds(lseg); |
|
} |
|
|
|
bool ff_layout_avoid_mds_available_ds(struct pnfs_layout_segment *lseg) |
|
{ |
|
return ff_layout_no_fallback_to_mds(lseg) || |
|
ff_layout_has_available_ds(lseg); |
|
} |
|
|
|
bool ff_layout_avoid_read_on_rw(struct pnfs_layout_segment *lseg) |
|
{ |
|
return lseg->pls_range.iomode == IOMODE_RW && |
|
ff_layout_no_read_on_rw(lseg); |
|
} |
|
|
|
module_param(dataserver_retrans, uint, 0644); |
|
MODULE_PARM_DESC(dataserver_retrans, "The number of times the NFSv4.1 client " |
|
"retries a request before it attempts further " |
|
" recovery action."); |
|
module_param(dataserver_timeo, uint, 0644); |
|
MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the " |
|
"NFSv4.1 client waits for a response from a " |
|
" data server before it retries an NFS request.");
|
|
|