diff options
author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /fs/nfs/pnfs.c | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'fs/nfs/pnfs.c')
-rw-r--r-- | fs/nfs/pnfs.c | 1319 |
1 files changed, 1319 insertions, 0 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c new file mode 100644 index 00000000..99518872 --- /dev/null +++ b/fs/nfs/pnfs.c @@ -0,0 +1,1319 @@ +/* + * pNFS functions to call and manage layout drivers. + * + * Copyright (c) 2002 [year of first publication] + * The Regents of the University of Michigan + * All Rights Reserved + * + * Dean Hildebrand <dhildebz@umich.edu> + * + * Permission is granted to use, copy, create derivative works, and + * redistribute this software and such derivative works for any purpose, + * so long as the name of the University of Michigan is not used in + * any advertising or publicity pertaining to the use or distribution + * of this software without specific, written prior authorization. If + * the above copyright notice or any other identification of the + * University of Michigan is included in any copy of any portion of + * this software, then the disclaimer below must also be included. + * + * This software is provided as is, without representation or warranty + * of any kind either express or implied, including without limitation + * the implied warranties of merchantability, fitness for a particular + * purpose, or noninfringement. The Regents of the University of + * Michigan shall not be liable for any damages, including special, + * indirect, incidental, or consequential damages, with respect to any + * claim arising out of or in connection with the use of the software, + * even if it has been or is hereafter advised of the possibility of + * such damages. + */ + +#include <linux/nfs_fs.h> +#include "internal.h" +#include "pnfs.h" +#include "iostat.h" + +#define NFSDBG_FACILITY NFSDBG_PNFS + +/* Locking: + * + * pnfs_spinlock: + * protects pnfs_modules_tbl. + */ +static DEFINE_SPINLOCK(pnfs_spinlock); + +/* + * pnfs_modules_tbl holds all pnfs modules + */ +static LIST_HEAD(pnfs_modules_tbl); + +/* Return the registered pnfs layout driver module matching given id */ +static struct pnfs_layoutdriver_type * +find_pnfs_driver_locked(u32 id) +{ + struct pnfs_layoutdriver_type *local; + + list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid) + if (local->id == id) + goto out; + local = NULL; +out: + dprintk("%s: Searching for id %u, found %p\n", __func__, id, local); + return local; +} + +static struct pnfs_layoutdriver_type * +find_pnfs_driver(u32 id) +{ + struct pnfs_layoutdriver_type *local; + + spin_lock(&pnfs_spinlock); + local = find_pnfs_driver_locked(id); + spin_unlock(&pnfs_spinlock); + return local; +} + +void +unset_pnfs_layoutdriver(struct nfs_server *nfss) +{ + if (nfss->pnfs_curr_ld) + module_put(nfss->pnfs_curr_ld->owner); + nfss->pnfs_curr_ld = NULL; +} + +/* + * Try to set the server's pnfs module to the pnfs layout type specified by id. + * Currently only one pNFS layout driver per filesystem is supported. + * + * @id layout type. Zero (illegal layout type) indicates pNFS not in use. + */ +void +set_pnfs_layoutdriver(struct nfs_server *server, u32 id) +{ + struct pnfs_layoutdriver_type *ld_type = NULL; + + if (id == 0) + goto out_no_driver; + if (!(server->nfs_client->cl_exchange_flags & + (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) { + printk(KERN_ERR "%s: id %u cl_exchange_flags 0x%x\n", __func__, + id, server->nfs_client->cl_exchange_flags); + goto out_no_driver; + } + ld_type = find_pnfs_driver(id); + if (!ld_type) { + request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id); + ld_type = find_pnfs_driver(id); + if (!ld_type) { + dprintk("%s: No pNFS module found for %u.\n", + __func__, id); + goto out_no_driver; + } + } + if (!try_module_get(ld_type->owner)) { + dprintk("%s: Could not grab reference on module\n", __func__); + goto out_no_driver; + } + server->pnfs_curr_ld = ld_type; + + dprintk("%s: pNFS module for %u set\n", __func__, id); + return; + +out_no_driver: + dprintk("%s: Using NFSv4 I/O\n", __func__); + server->pnfs_curr_ld = NULL; +} + +int +pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type) +{ + int status = -EINVAL; + struct pnfs_layoutdriver_type *tmp; + + if (ld_type->id == 0) { + printk(KERN_ERR "%s id 0 is reserved\n", __func__); + return status; + } + if (!ld_type->alloc_lseg || !ld_type->free_lseg) { + printk(KERN_ERR "%s Layout driver must provide " + "alloc_lseg and free_lseg.\n", __func__); + return status; + } + + spin_lock(&pnfs_spinlock); + tmp = find_pnfs_driver_locked(ld_type->id); + if (!tmp) { + list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl); + status = 0; + dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id, + ld_type->name); + } else { + printk(KERN_ERR "%s Module with id %d already loaded!\n", + __func__, ld_type->id); + } + spin_unlock(&pnfs_spinlock); + + return status; +} +EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver); + +void +pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type) +{ + dprintk("%s Deregistering id:%u\n", __func__, ld_type->id); + spin_lock(&pnfs_spinlock); + list_del(&ld_type->pnfs_tblid); + spin_unlock(&pnfs_spinlock); +} +EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver); + +/* + * pNFS client layout cache + */ + +/* Need to hold i_lock if caller does not already hold reference */ +void +get_layout_hdr(struct pnfs_layout_hdr *lo) +{ + atomic_inc(&lo->plh_refcount); +} + +static struct pnfs_layout_hdr * +pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags) +{ + struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld; + return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) : + kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags); +} + +static void +pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo) +{ + struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld; + put_rpccred(lo->plh_lc_cred); + return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo); +} + +static void +destroy_layout_hdr(struct pnfs_layout_hdr *lo) +{ + dprintk("%s: freeing layout cache %p\n", __func__, lo); + BUG_ON(!list_empty(&lo->plh_layouts)); + NFS_I(lo->plh_inode)->layout = NULL; + pnfs_free_layout_hdr(lo); +} + +static void +put_layout_hdr_locked(struct pnfs_layout_hdr *lo) +{ + if (atomic_dec_and_test(&lo->plh_refcount)) + destroy_layout_hdr(lo); +} + +void +put_layout_hdr(struct pnfs_layout_hdr *lo) +{ + struct inode *inode = lo->plh_inode; + + if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) { + destroy_layout_hdr(lo); + spin_unlock(&inode->i_lock); + } +} + +static void +init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg) +{ + INIT_LIST_HEAD(&lseg->pls_list); + INIT_LIST_HEAD(&lseg->pls_lc_list); + atomic_set(&lseg->pls_refcount, 1); + smp_mb(); + set_bit(NFS_LSEG_VALID, &lseg->pls_flags); + lseg->pls_layout = lo; +} + +static void free_lseg(struct pnfs_layout_segment *lseg) +{ + struct inode *ino = lseg->pls_layout->plh_inode; + + NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg); + /* Matched by get_layout_hdr in pnfs_insert_layout */ + put_layout_hdr(NFS_I(ino)->layout); +} + +static void +put_lseg_common(struct pnfs_layout_segment *lseg) +{ + struct inode *inode = lseg->pls_layout->plh_inode; + + WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); + list_del_init(&lseg->pls_list); + if (list_empty(&lseg->pls_layout->plh_segs)) { + set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags); + /* Matched by initial refcount set in alloc_init_layout_hdr */ + put_layout_hdr_locked(lseg->pls_layout); + } + rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq); +} + +void +put_lseg(struct pnfs_layout_segment *lseg) +{ + struct inode *inode; + + if (!lseg) + return; + + dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg, + atomic_read(&lseg->pls_refcount), + test_bit(NFS_LSEG_VALID, &lseg->pls_flags)); + inode = lseg->pls_layout->plh_inode; + if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) { + LIST_HEAD(free_me); + + put_lseg_common(lseg); + list_add(&lseg->pls_list, &free_me); + spin_unlock(&inode->i_lock); + pnfs_free_lseg_list(&free_me); + } +} +EXPORT_SYMBOL_GPL(put_lseg); + +static inline u64 +end_offset(u64 start, u64 len) +{ + u64 end; + + end = start + len; + return end >= start ? end : NFS4_MAX_UINT64; +} + +/* last octet in a range */ +static inline u64 +last_byte_offset(u64 start, u64 len) +{ + u64 end; + + BUG_ON(!len); + end = start + len; + return end > start ? end - 1 : NFS4_MAX_UINT64; +} + +/* + * is l2 fully contained in l1? + * start1 end1 + * [----------------------------------) + * start2 end2 + * [----------------) + */ +static inline int +lo_seg_contained(struct pnfs_layout_range *l1, + struct pnfs_layout_range *l2) +{ + u64 start1 = l1->offset; + u64 end1 = end_offset(start1, l1->length); + u64 start2 = l2->offset; + u64 end2 = end_offset(start2, l2->length); + + return (start1 <= start2) && (end1 >= end2); +} + +/* + * is l1 and l2 intersecting? + * start1 end1 + * [----------------------------------) + * start2 end2 + * [----------------) + */ +static inline int +lo_seg_intersecting(struct pnfs_layout_range *l1, + struct pnfs_layout_range *l2) +{ + u64 start1 = l1->offset; + u64 end1 = end_offset(start1, l1->length); + u64 start2 = l2->offset; + u64 end2 = end_offset(start2, l2->length); + + return (end1 == NFS4_MAX_UINT64 || end1 > start2) && + (end2 == NFS4_MAX_UINT64 || end2 > start1); +} + +static bool +should_free_lseg(struct pnfs_layout_range *lseg_range, + struct pnfs_layout_range *recall_range) +{ + return (recall_range->iomode == IOMODE_ANY || + lseg_range->iomode == recall_range->iomode) && + lo_seg_intersecting(lseg_range, recall_range); +} + +/* Returns 1 if lseg is removed from list, 0 otherwise */ +static int mark_lseg_invalid(struct pnfs_layout_segment *lseg, + struct list_head *tmp_list) +{ + int rv = 0; + + if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) { + /* Remove the reference keeping the lseg in the + * list. It will now be removed when all + * outstanding io is finished. + */ + dprintk("%s: lseg %p ref %d\n", __func__, lseg, + atomic_read(&lseg->pls_refcount)); + if (atomic_dec_and_test(&lseg->pls_refcount)) { + put_lseg_common(lseg); + list_add(&lseg->pls_list, tmp_list); + rv = 1; + } + } + return rv; +} + +/* Returns count of number of matching invalid lsegs remaining in list + * after call. + */ +int +mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo, + struct list_head *tmp_list, + struct pnfs_layout_range *recall_range) +{ + struct pnfs_layout_segment *lseg, *next; + int invalid = 0, removed = 0; + + dprintk("%s:Begin lo %p\n", __func__, lo); + + if (list_empty(&lo->plh_segs)) { + if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) + put_layout_hdr_locked(lo); + return 0; + } + list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list) + if (!recall_range || + should_free_lseg(&lseg->pls_range, recall_range)) { + dprintk("%s: freeing lseg %p iomode %d " + "offset %llu length %llu\n", __func__, + lseg, lseg->pls_range.iomode, lseg->pls_range.offset, + lseg->pls_range.length); + invalid++; + removed += mark_lseg_invalid(lseg, tmp_list); + } + dprintk("%s:Return %i\n", __func__, invalid - removed); + return invalid - removed; +} + +/* note free_me must contain lsegs from a single layout_hdr */ +void +pnfs_free_lseg_list(struct list_head *free_me) +{ + struct pnfs_layout_segment *lseg, *tmp; + struct pnfs_layout_hdr *lo; + + if (list_empty(free_me)) + return; + + lo = list_first_entry(free_me, struct pnfs_layout_segment, + pls_list)->pls_layout; + + if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) { + struct nfs_client *clp; + + clp = NFS_SERVER(lo->plh_inode)->nfs_client; + spin_lock(&clp->cl_lock); + list_del_init(&lo->plh_layouts); + spin_unlock(&clp->cl_lock); + } + list_for_each_entry_safe(lseg, tmp, free_me, pls_list) { + list_del(&lseg->pls_list); + free_lseg(lseg); + } +} + +void +pnfs_destroy_layout(struct nfs_inode *nfsi) +{ + struct pnfs_layout_hdr *lo; + LIST_HEAD(tmp_list); + + spin_lock(&nfsi->vfs_inode.i_lock); + lo = nfsi->layout; + if (lo) { + lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */ + mark_matching_lsegs_invalid(lo, &tmp_list, NULL); + } + spin_unlock(&nfsi->vfs_inode.i_lock); + pnfs_free_lseg_list(&tmp_list); +} + +/* + * Called by the state manger to remove all layouts established under an + * expired lease. + */ +void +pnfs_destroy_all_layouts(struct nfs_client *clp) +{ + struct pnfs_layout_hdr *lo; + LIST_HEAD(tmp_list); + + spin_lock(&clp->cl_lock); + list_splice_init(&clp->cl_layouts, &tmp_list); + spin_unlock(&clp->cl_lock); + + while (!list_empty(&tmp_list)) { + lo = list_entry(tmp_list.next, struct pnfs_layout_hdr, + plh_layouts); + dprintk("%s freeing layout for inode %lu\n", __func__, + lo->plh_inode->i_ino); + list_del_init(&lo->plh_layouts); + pnfs_destroy_layout(NFS_I(lo->plh_inode)); + } +} + +/* update lo->plh_stateid with new if is more recent */ +void +pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new, + bool update_barrier) +{ + u32 oldseq, newseq; + + oldseq = be32_to_cpu(lo->plh_stateid.stateid.seqid); + newseq = be32_to_cpu(new->stateid.seqid); + if ((int)(newseq - oldseq) > 0) { + memcpy(&lo->plh_stateid, &new->stateid, sizeof(new->stateid)); + if (update_barrier) { + u32 new_barrier = be32_to_cpu(new->stateid.seqid); + + if ((int)(new_barrier - lo->plh_barrier)) + lo->plh_barrier = new_barrier; + } else { + /* Because of wraparound, we want to keep the barrier + * "close" to the current seqids. It needs to be + * within 2**31 to count as "behind", so if it + * gets too near that limit, give us a litle leeway + * and bring it to within 2**30. + * NOTE - and yes, this is all unsigned arithmetic. + */ + if (unlikely((newseq - lo->plh_barrier) > (3 << 29))) + lo->plh_barrier = newseq - (1 << 30); + } + } +} + +/* lget is set to 1 if called from inside send_layoutget call chain */ +static bool +pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid, + int lget) +{ + if ((stateid) && + (int)(lo->plh_barrier - be32_to_cpu(stateid->stateid.seqid)) >= 0) + return true; + return lo->plh_block_lgets || + test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) || + test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) || + (list_empty(&lo->plh_segs) && + (atomic_read(&lo->plh_outstanding) > lget)); +} + +int +pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo, + struct nfs4_state *open_state) +{ + int status = 0; + + dprintk("--> %s\n", __func__); + spin_lock(&lo->plh_inode->i_lock); + if (pnfs_layoutgets_blocked(lo, NULL, 1)) { + status = -EAGAIN; + } else if (list_empty(&lo->plh_segs)) { + int seq; + + do { + seq = read_seqbegin(&open_state->seqlock); + memcpy(dst->data, open_state->stateid.data, + sizeof(open_state->stateid.data)); + } while (read_seqretry(&open_state->seqlock, seq)); + } else + memcpy(dst->data, lo->plh_stateid.data, sizeof(lo->plh_stateid.data)); + spin_unlock(&lo->plh_inode->i_lock); + dprintk("<-- %s\n", __func__); + return status; +} + +/* +* Get layout from server. +* for now, assume that whole file layouts are requested. +* arg->offset: 0 +* arg->length: all ones +*/ +static struct pnfs_layout_segment * +send_layoutget(struct pnfs_layout_hdr *lo, + struct nfs_open_context *ctx, + struct pnfs_layout_range *range, + gfp_t gfp_flags) +{ + struct inode *ino = lo->plh_inode; + struct nfs_server *server = NFS_SERVER(ino); + struct nfs4_layoutget *lgp; + struct pnfs_layout_segment *lseg = NULL; + struct page **pages = NULL; + int i; + u32 max_resp_sz, max_pages; + + dprintk("--> %s\n", __func__); + + BUG_ON(ctx == NULL); + lgp = kzalloc(sizeof(*lgp), gfp_flags); + if (lgp == NULL) + return NULL; + + /* allocate pages for xdr post processing */ + max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz; + max_pages = max_resp_sz >> PAGE_SHIFT; + + pages = kzalloc(max_pages * sizeof(struct page *), gfp_flags); + if (!pages) + goto out_err_free; + + for (i = 0; i < max_pages; i++) { + pages[i] = alloc_page(gfp_flags); + if (!pages[i]) + goto out_err_free; + } + + lgp->args.minlength = PAGE_CACHE_SIZE; + if (lgp->args.minlength > range->length) + lgp->args.minlength = range->length; + lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE; + lgp->args.range = *range; + lgp->args.type = server->pnfs_curr_ld->id; + lgp->args.inode = ino; + lgp->args.ctx = get_nfs_open_context(ctx); + lgp->args.layout.pages = pages; + lgp->args.layout.pglen = max_pages * PAGE_SIZE; + lgp->lsegpp = &lseg; + lgp->gfp_flags = gfp_flags; + + /* Synchronously retrieve layout information from server and + * store in lseg. + */ + nfs4_proc_layoutget(lgp); + if (!lseg) { + /* remember that LAYOUTGET failed and suspend trying */ + set_bit(lo_fail_bit(range->iomode), &lo->plh_flags); + } + + /* free xdr pages */ + for (i = 0; i < max_pages; i++) + __free_page(pages[i]); + kfree(pages); + + return lseg; + +out_err_free: + /* free any allocated xdr pages, lgp as it's not used */ + if (pages) { + for (i = 0; i < max_pages; i++) { + if (!pages[i]) + break; + __free_page(pages[i]); + } + kfree(pages); + } + kfree(lgp); + return NULL; +} + +/* Initiates a LAYOUTRETURN(FILE) */ +int +_pnfs_return_layout(struct inode *ino) +{ + struct pnfs_layout_hdr *lo = NULL; + struct nfs_inode *nfsi = NFS_I(ino); + LIST_HEAD(tmp_list); + struct nfs4_layoutreturn *lrp; + nfs4_stateid stateid; + int status = 0; + + dprintk("--> %s\n", __func__); + + spin_lock(&ino->i_lock); + lo = nfsi->layout; + if (!lo) { + spin_unlock(&ino->i_lock); + dprintk("%s: no layout to return\n", __func__); + return status; + } + stateid = nfsi->layout->plh_stateid; + /* Reference matched in nfs4_layoutreturn_release */ + get_layout_hdr(lo); + mark_matching_lsegs_invalid(lo, &tmp_list, NULL); + lo->plh_block_lgets++; + spin_unlock(&ino->i_lock); + pnfs_free_lseg_list(&tmp_list); + + WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)); + + lrp = kzalloc(sizeof(*lrp), GFP_KERNEL); + if (unlikely(lrp == NULL)) { + status = -ENOMEM; + set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags); + set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags); + put_layout_hdr(lo); + goto out; + } + + lrp->args.stateid = stateid; + lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id; + lrp->args.inode = ino; + lrp->clp = NFS_SERVER(ino)->nfs_client; + + status = nfs4_proc_layoutreturn(lrp); +out: + dprintk("<-- %s status: %d\n", __func__, status); + return status; +} + +bool pnfs_roc(struct inode *ino) +{ + struct pnfs_layout_hdr *lo; + struct pnfs_layout_segment *lseg, *tmp; + LIST_HEAD(tmp_list); + bool found = false; + + spin_lock(&ino->i_lock); + lo = NFS_I(ino)->layout; + if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) || + test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) + goto out_nolayout; + list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list) + if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) { + mark_lseg_invalid(lseg, &tmp_list); + found = true; + } + if (!found) + goto out_nolayout; + lo->plh_block_lgets++; + get_layout_hdr(lo); /* matched in pnfs_roc_release */ + spin_unlock(&ino->i_lock); + pnfs_free_lseg_list(&tmp_list); + return true; + +out_nolayout: + spin_unlock(&ino->i_lock); + return false; +} + +void pnfs_roc_release(struct inode *ino) +{ + struct pnfs_layout_hdr *lo; + + spin_lock(&ino->i_lock); + lo = NFS_I(ino)->layout; + lo->plh_block_lgets--; + put_layout_hdr_locked(lo); + spin_unlock(&ino->i_lock); +} + +void pnfs_roc_set_barrier(struct inode *ino, u32 barrier) +{ + struct pnfs_layout_hdr *lo; + + spin_lock(&ino->i_lock); + lo = NFS_I(ino)->layout; + if ((int)(barrier - lo->plh_barrier) > 0) + lo->plh_barrier = barrier; + spin_unlock(&ino->i_lock); +} + +bool pnfs_roc_drain(struct inode *ino, u32 *barrier) +{ + struct nfs_inode *nfsi = NFS_I(ino); + struct pnfs_layout_segment *lseg; + bool found = false; + + spin_lock(&ino->i_lock); + list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list) + if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) { + found = true; + break; + } + if (!found) { + struct pnfs_layout_hdr *lo = nfsi->layout; + u32 current_seqid = be32_to_cpu(lo->plh_stateid.stateid.seqid); + + /* Since close does not return a layout stateid for use as + * a barrier, we choose the worst-case barrier. + */ + *barrier = current_seqid + atomic_read(&lo->plh_outstanding); + } + spin_unlock(&ino->i_lock); + return found; +} + +/* + * Compare two layout segments for sorting into layout cache. + * We want to preferentially return RW over RO layouts, so ensure those + * are seen first. + */ +static s64 +cmp_layout(struct pnfs_layout_range *l1, + struct pnfs_layout_range *l2) +{ + s64 d; + + /* high offset > low offset */ + d = l1->offset - l2->offset; + if (d) + return d; + + /* short length > long length */ + d = l2->length - l1->length; + if (d) + return d; + + /* read > read/write */ + return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ); +} + +static void +pnfs_insert_layout(struct pnfs_layout_hdr *lo, + struct pnfs_layout_segment *lseg) +{ + struct pnfs_layout_segment *lp; + + dprintk("%s:Begin\n", __func__); + + assert_spin_locked(&lo->plh_inode->i_lock); + list_for_each_entry(lp, &lo->plh_segs, pls_list) { + if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0) + continue; + list_add_tail(&lseg->pls_list, &lp->pls_list); + dprintk("%s: inserted lseg %p " + "iomode %d offset %llu length %llu before " + "lp %p iomode %d offset %llu length %llu\n", + __func__, lseg, lseg->pls_range.iomode, + lseg->pls_range.offset, lseg->pls_range.length, + lp, lp->pls_range.iomode, lp->pls_range.offset, + lp->pls_range.length); + goto out; + } + list_add_tail(&lseg->pls_list, &lo->plh_segs); + dprintk("%s: inserted lseg %p " + "iomode %d offset %llu length %llu at tail\n", + __func__, lseg, lseg->pls_range.iomode, + lseg->pls_range.offset, lseg->pls_range.length); +out: + get_layout_hdr(lo); + + dprintk("%s:Return\n", __func__); +} + +static struct pnfs_layout_hdr * +alloc_init_layout_hdr(struct inode *ino, + struct nfs_open_context *ctx, + gfp_t gfp_flags) +{ + struct pnfs_layout_hdr *lo; + + lo = pnfs_alloc_layout_hdr(ino, gfp_flags); + if (!lo) + return NULL; + atomic_set(&lo->plh_refcount, 1); + INIT_LIST_HEAD(&lo->plh_layouts); + INIT_LIST_HEAD(&lo->plh_segs); + INIT_LIST_HEAD(&lo->plh_bulk_recall); + lo->plh_inode = ino; + lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred); + return lo; +} + +static struct pnfs_layout_hdr * +pnfs_find_alloc_layout(struct inode *ino, + struct nfs_open_context *ctx, + gfp_t gfp_flags) +{ + struct nfs_inode *nfsi = NFS_I(ino); + struct pnfs_layout_hdr *new = NULL; + + dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout); + + assert_spin_locked(&ino->i_lock); + if (nfsi->layout) { + if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags)) + return NULL; + else + return nfsi->layout; + } + spin_unlock(&ino->i_lock); + new = alloc_init_layout_hdr(ino, ctx, gfp_flags); + spin_lock(&ino->i_lock); + + if (likely(nfsi->layout == NULL)) /* Won the race? */ + nfsi->layout = new; + else + pnfs_free_layout_hdr(new); + return nfsi->layout; +} + +/* + * iomode matching rules: + * iomode lseg match + * ----- ----- ----- + * ANY READ true + * ANY RW true + * RW READ false + * RW RW true + * READ READ true + * READ RW true + */ +static int +is_matching_lseg(struct pnfs_layout_range *ls_range, + struct pnfs_layout_range *range) +{ + struct pnfs_layout_range range1; + + if ((range->iomode == IOMODE_RW && + ls_range->iomode != IOMODE_RW) || + !lo_seg_intersecting(ls_range, range)) + return 0; + + /* range1 covers only the first byte in the range */ + range1 = *range; + range1.length = 1; + return lo_seg_contained(ls_range, &range1); +} + +/* + * lookup range in layout + */ +static struct pnfs_layout_segment * +pnfs_find_lseg(struct pnfs_layout_hdr *lo, + struct pnfs_layout_range *range) +{ + struct pnfs_layout_segment *lseg, *ret = NULL; + + dprintk("%s:Begin\n", __func__); + + assert_spin_locked(&lo->plh_inode->i_lock); + list_for_each_entry(lseg, &lo->plh_segs, pls_list) { + if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) && + is_matching_lseg(&lseg->pls_range, range)) { + ret = get_lseg(lseg); + break; + } + if (lseg->pls_range.offset > range->offset) + break; + } + + dprintk("%s:Return lseg %p ref %d\n", + __func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0); + return ret; +} + +/* + * Layout segment is retreived from the server if not cached. + * The appropriate layout segment is referenced and returned to the caller. + */ +struct pnfs_layout_segment * +pnfs_update_layout(struct inode *ino, + struct nfs_open_context *ctx, + loff_t pos, + u64 count, + enum pnfs_iomode iomode, + gfp_t gfp_flags) +{ + struct pnfs_layout_range arg = { + .iomode = iomode, + .offset = pos, + .length = count, + }; + unsigned pg_offset; + struct nfs_inode *nfsi = NFS_I(ino); + struct nfs_client *clp = NFS_SERVER(ino)->nfs_client; + struct pnfs_layout_hdr *lo; + struct pnfs_layout_segment *lseg = NULL; + bool first = false; + + if (!pnfs_enabled_sb(NFS_SERVER(ino))) + return NULL; + spin_lock(&ino->i_lock); + lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags); + if (lo == NULL) { + dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__); + goto out_unlock; + } + + /* Do we even need to bother with this? */ + if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) || + test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { + dprintk("%s matches recall, use MDS\n", __func__); + goto out_unlock; + } + + /* if LAYOUTGET already failed once we don't try again */ + if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags)) + goto out_unlock; + + /* Check to see if the layout for the given range already exists */ + lseg = pnfs_find_lseg(lo, &arg); + if (lseg) + goto out_unlock; + + if (pnfs_layoutgets_blocked(lo, NULL, 0)) + goto out_unlock; + atomic_inc(&lo->plh_outstanding); + + get_layout_hdr(lo); + if (list_empty(&lo->plh_segs)) + first = true; + spin_unlock(&ino->i_lock); + if (first) { + /* The lo must be on the clp list if there is any + * chance of a CB_LAYOUTRECALL(FILE) coming in. + */ + spin_lock(&clp->cl_lock); + BUG_ON(!list_empty(&lo->plh_layouts)); + list_add_tail(&lo->plh_layouts, &clp->cl_layouts); + spin_unlock(&clp->cl_lock); + } + + pg_offset = arg.offset & ~PAGE_CACHE_MASK; + if (pg_offset) { + arg.offset -= pg_offset; + arg.length += pg_offset; + } + if (arg.length != NFS4_MAX_UINT64) + arg.length = PAGE_CACHE_ALIGN(arg.length); + + lseg = send_layoutget(lo, ctx, &arg, gfp_flags); + if (!lseg && first) { + spin_lock(&clp->cl_lock); + list_del_init(&lo->plh_layouts); + spin_unlock(&clp->cl_lock); + } + atomic_dec(&lo->plh_outstanding); + put_layout_hdr(lo); +out: + dprintk("%s end, state 0x%lx lseg %p\n", __func__, + nfsi->layout ? nfsi->layout->plh_flags : -1, lseg); + return lseg; +out_unlock: + spin_unlock(&ino->i_lock); + goto out; +} + +int +pnfs_layout_process(struct nfs4_layoutget *lgp) +{ + struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout; + struct nfs4_layoutget_res *res = &lgp->res; + struct pnfs_layout_segment *lseg; + struct inode *ino = lo->plh_inode; + struct nfs_client *clp = NFS_SERVER(ino)->nfs_client; + int status = 0; + + /* Inject layout blob into I/O device driver */ + lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags); + if (!lseg || IS_ERR(lseg)) { + if (!lseg) + status = -ENOMEM; + else + status = PTR_ERR(lseg); + dprintk("%s: Could not allocate layout: error %d\n", + __func__, status); + goto out; + } + + spin_lock(&ino->i_lock); + if (test_bit(NFS4CLNT_LAYOUTRECALL, &clp->cl_state) || + test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) { + dprintk("%s forget reply due to recall\n", __func__); + goto out_forget_reply; + } + + if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) { + dprintk("%s forget reply due to state\n", __func__); + goto out_forget_reply; + } + init_lseg(lo, lseg); + lseg->pls_range = res->range; + *lgp->lsegpp = get_lseg(lseg); + pnfs_insert_layout(lo, lseg); + + if (res->return_on_close) { + set_bit(NFS_LSEG_ROC, &lseg->pls_flags); + set_bit(NFS_LAYOUT_ROC, &lo->plh_flags); + } + + /* Done processing layoutget. Set the layout stateid */ + pnfs_set_layout_stateid(lo, &res->stateid, false); + spin_unlock(&ino->i_lock); +out: + return status; + +out_forget_reply: + spin_unlock(&ino->i_lock); + lseg->pls_layout = lo; + NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg); + goto out; +} + +bool +pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev, + struct nfs_page *req) +{ + enum pnfs_iomode access_type; + gfp_t gfp_flags; + + /* We assume that pg_ioflags == 0 iff we're reading a page */ + if (pgio->pg_ioflags == 0) { + access_type = IOMODE_READ; + gfp_flags = GFP_KERNEL; + } else { + access_type = IOMODE_RW; + gfp_flags = GFP_NOFS; + } + + if (pgio->pg_lseg == NULL) { + if (pgio->pg_count != prev->wb_bytes) + return true; + /* This is first coelesce call for a series of nfs_pages */ + pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode, + prev->wb_context, + req_offset(prev), + pgio->pg_count, + access_type, + gfp_flags); + if (pgio->pg_lseg == NULL) + return true; + } + + /* + * Test if a nfs_page is fully contained in the pnfs_layout_range. + * Note that this test makes several assumptions: + * - that the previous nfs_page in the struct nfs_pageio_descriptor + * is known to lie within the range. + * - that the nfs_page being tested is known to be contiguous with the + * previous nfs_page. + * - Layout ranges are page aligned, so we only have to test the + * start offset of the request. + * + * Please also note that 'end_offset' is actually the offset of the + * first byte that lies outside the pnfs_layout_range. FIXME? + * + */ + return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset, + pgio->pg_lseg->pls_range.length); +} +EXPORT_SYMBOL_GPL(pnfs_generic_pg_test); + +/* + * Called by non rpc-based layout drivers + */ +int +pnfs_ld_write_done(struct nfs_write_data *data) +{ + int status; + + if (!data->pnfs_error) { + pnfs_set_layoutcommit(data); + data->mds_ops->rpc_call_done(&data->task, data); + data->mds_ops->rpc_release(data); + return 0; + } + if (NFS_SERVER(data->inode)->pnfs_curr_ld->flags & + PNFS_LAYOUTRET_ON_ERROR) { + /* Don't lo_commit on error, Server will needs to + * preform a file recovery. + */ + clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(data->inode)->flags); + pnfs_return_layout(data->inode); + } + + dprintk("%s: pnfs_error=%d, retry via MDS\n", __func__, + data->pnfs_error); + status = nfs_initiate_write(data, NFS_CLIENT(data->inode), + data->mds_ops, NFS_FILE_SYNC); + return status ? : -EAGAIN; +} +EXPORT_SYMBOL_GPL(pnfs_ld_write_done); + +enum pnfs_try_status +pnfs_try_to_write_data(struct nfs_write_data *wdata, + const struct rpc_call_ops *call_ops, int how) +{ + struct inode *inode = wdata->inode; + enum pnfs_try_status trypnfs; + struct nfs_server *nfss = NFS_SERVER(inode); + + wdata->mds_ops = call_ops; + + dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__, + inode->i_ino, wdata->args.count, wdata->args.offset, how); + + trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how); + if (trypnfs == PNFS_NOT_ATTEMPTED) { + put_lseg(wdata->lseg); + wdata->lseg = NULL; + } else + nfs_inc_stats(inode, NFSIOS_PNFS_WRITE); + + dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs); + return trypnfs; +} + +/* + * Called by non rpc-based layout drivers + */ +int +pnfs_ld_read_done(struct nfs_read_data *data) +{ + int status; + + if (!data->pnfs_error) { + __nfs4_read_done_cb(data); + data->mds_ops->rpc_call_done(&data->task, data); + data->mds_ops->rpc_release(data); + return 0; + } + + if (NFS_SERVER(data->inode)->pnfs_curr_ld->flags & + PNFS_LAYOUTRET_ON_ERROR) + pnfs_return_layout(data->inode); + + dprintk("%s: pnfs_error=%d, retry via MDS\n", __func__, + data->pnfs_error); + status = nfs_initiate_read(data, NFS_CLIENT(data->inode), + data->mds_ops); + return status ? : -EAGAIN; +} +EXPORT_SYMBOL_GPL(pnfs_ld_read_done); + +/* + * Call the appropriate parallel I/O subsystem read function. + */ +enum pnfs_try_status +pnfs_try_to_read_data(struct nfs_read_data *rdata, + const struct rpc_call_ops *call_ops) +{ + struct inode *inode = rdata->inode; + struct nfs_server *nfss = NFS_SERVER(inode); + enum pnfs_try_status trypnfs; + + rdata->mds_ops = call_ops; + + dprintk("%s: Reading ino:%lu %u@%llu\n", + __func__, inode->i_ino, rdata->args.count, rdata->args.offset); + + trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata); + if (trypnfs == PNFS_NOT_ATTEMPTED) { + put_lseg(rdata->lseg); + rdata->lseg = NULL; + } else { + nfs_inc_stats(inode, NFSIOS_PNFS_READ); + } + dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs); + return trypnfs; +} + +/* + * There can be multiple RW segments. + */ +static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp) +{ + struct pnfs_layout_segment *lseg; + + list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) { + if (lseg->pls_range.iomode == IOMODE_RW && + test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) + list_add(&lseg->pls_lc_list, listp); + } +} + +void +pnfs_set_layoutcommit(struct nfs_write_data *wdata) +{ + struct nfs_inode *nfsi = NFS_I(wdata->inode); + loff_t end_pos = wdata->mds_offset + wdata->res.count; + bool mark_as_dirty = false; + + spin_lock(&nfsi->vfs_inode.i_lock); + if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) { + mark_as_dirty = true; + dprintk("%s: Set layoutcommit for inode %lu ", + __func__, wdata->inode->i_ino); + } + if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) { + /* references matched in nfs4_layoutcommit_release */ + get_lseg(wdata->lseg); + } + if (end_pos > nfsi->layout->plh_lwb) + nfsi->layout->plh_lwb = end_pos; + spin_unlock(&nfsi->vfs_inode.i_lock); + dprintk("%s: lseg %p end_pos %llu\n", + __func__, wdata->lseg, nfsi->layout->plh_lwb); + + /* if pnfs_layoutcommit_inode() runs between inode locks, the next one + * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */ + if (mark_as_dirty) + mark_inode_dirty_sync(wdata->inode); +} +EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit); + +/* + * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and + * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough + * data to disk to allow the server to recover the data if it crashes. + * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag + * is off, and a COMMIT is sent to a data server, or + * if WRITEs to a data server return NFS_DATA_SYNC. + */ +int +pnfs_layoutcommit_inode(struct inode *inode, bool sync) +{ + struct nfs4_layoutcommit_data *data; + struct nfs_inode *nfsi = NFS_I(inode); + loff_t end_pos; + int status = 0; + + dprintk("--> %s inode %lu\n", __func__, inode->i_ino); + + if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) + return 0; + + /* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */ + data = kzalloc(sizeof(*data), GFP_NOFS); + if (!data) { + mark_inode_dirty_sync(inode); + status = -ENOMEM; + goto out; + } + + INIT_LIST_HEAD(&data->lseg_list); + spin_lock(&inode->i_lock); + if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) { + spin_unlock(&inode->i_lock); + kfree(data); + goto out; + } + + pnfs_list_write_lseg(inode, &data->lseg_list); + + end_pos = nfsi->layout->plh_lwb; + nfsi->layout->plh_lwb = 0; + + memcpy(&data->args.stateid.data, nfsi->layout->plh_stateid.data, + sizeof(nfsi->layout->plh_stateid.data)); + spin_unlock(&inode->i_lock); + + data->args.inode = inode; + data->cred = get_rpccred(nfsi->layout->plh_lc_cred); + nfs_fattr_init(&data->fattr); + data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask; + data->res.fattr = &data->fattr; + data->args.lastbytewritten = end_pos - 1; + data->res.server = NFS_SERVER(inode); + + status = nfs4_proc_layoutcommit(data, sync); +out: + dprintk("<-- %s status %d\n", __func__, status); + return status; +} |