diff options
Diffstat (limited to 'fs/nfs/dir.c')
-rw-r--r-- | fs/nfs/dir.c | 338 |
1 files changed, 279 insertions, 59 deletions
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index e7ffb4deb3e5..3419c2da9ba9 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -30,7 +30,9 @@ #include <linux/nfs_mount.h> #include <linux/pagemap.h> #include <linux/smp_lock.h> +#include <linux/pagevec.h> #include <linux/namei.h> +#include <linux/mount.h> #include "nfs4_fs.h" #include "delegation.h" @@ -870,14 +872,14 @@ int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd) return (nd->intent.open.flags & O_EXCL) != 0; } -static inline int nfs_reval_fsid(struct inode *dir, - struct nfs_fh *fh, struct nfs_fattr *fattr) +static inline int nfs_reval_fsid(struct vfsmount *mnt, struct inode *dir, + struct nfs_fh *fh, struct nfs_fattr *fattr) { struct nfs_server *server = NFS_SERVER(dir); if (!nfs_fsid_equal(&server->fsid, &fattr->fsid)) /* Revalidate fsid on root dir */ - return __nfs_revalidate_inode(server, dir->i_sb->s_root->d_inode); + return __nfs_revalidate_inode(server, mnt->mnt_root->d_inode); return 0; } @@ -902,9 +904,15 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru lock_kernel(); - /* If we're doing an exclusive create, optimize away the lookup */ - if (nfs_is_exclusive_create(dir, nd)) - goto no_entry; + /* + * If we're doing an exclusive create, optimize away the lookup + * but don't hash the dentry. + */ + if (nfs_is_exclusive_create(dir, nd)) { + d_instantiate(dentry, NULL); + res = NULL; + goto out_unlock; + } error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr); if (error == -ENOENT) @@ -913,7 +921,7 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru res = ERR_PTR(error); goto out_unlock; } - error = nfs_reval_fsid(dir, &fhandle, &fattr); + error = nfs_reval_fsid(nd->mnt, dir, &fhandle, &fattr); if (error < 0) { res = ERR_PTR(error); goto out_unlock; @@ -922,8 +930,9 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru res = (struct dentry *)inode; if (IS_ERR(res)) goto out_unlock; + no_entry: - res = d_add_unique(dentry, inode); + res = d_materialise_unique(dentry, inode); if (res != NULL) dentry = res; nfs_renew_times(dentry); @@ -1117,11 +1126,13 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc) dput(dentry); return NULL; } - alias = d_add_unique(dentry, inode); + + alias = d_materialise_unique(dentry, inode); if (alias != NULL) { dput(dentry); dentry = alias; } + nfs_renew_times(dentry); nfs_set_verifier(dentry, nfs_save_change_attribute(dir)); return dentry; @@ -1143,23 +1154,22 @@ int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle, struct inode *dir = dentry->d_parent->d_inode; error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr); if (error) - goto out_err; + return error; } if (!(fattr->valid & NFS_ATTR_FATTR)) { struct nfs_server *server = NFS_SB(dentry->d_sb); - error = server->rpc_ops->getattr(server, fhandle, fattr); + error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr); if (error < 0) - goto out_err; + return error; } inode = nfs_fhget(dentry->d_sb, fhandle, fattr); error = PTR_ERR(inode); if (IS_ERR(inode)) - goto out_err; + return error; d_instantiate(dentry, inode); + if (d_unhashed(dentry)) + d_rehash(dentry); return 0; -out_err: - d_drop(dentry); - return error; } /* @@ -1440,48 +1450,82 @@ static int nfs_unlink(struct inode *dir, struct dentry *dentry) return error; } -static int -nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) +/* + * To create a symbolic link, most file systems instantiate a new inode, + * add a page to it containing the path, then write it out to the disk + * using prepare_write/commit_write. + * + * Unfortunately the NFS client can't create the in-core inode first + * because it needs a file handle to create an in-core inode (see + * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the + * symlink request has completed on the server. + * + * So instead we allocate a raw page, copy the symname into it, then do + * the SYMLINK request with the page as the buffer. If it succeeds, we + * now have a new file handle and can instantiate an in-core NFS inode + * and move the raw page into its mapping. + */ +static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { + struct pagevec lru_pvec; + struct page *page; + char *kaddr; struct iattr attr; - struct nfs_fattr sym_attr; - struct nfs_fh sym_fh; - struct qstr qsymname; + unsigned int pathlen = strlen(symname); int error; dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id, dir->i_ino, dentry->d_name.name, symname); -#ifdef NFS_PARANOIA -if (dentry->d_inode) -printk("nfs_proc_symlink: %s/%s not negative!\n", -dentry->d_parent->d_name.name, dentry->d_name.name); -#endif - /* - * Fill in the sattr for the call. - * Note: SunOS 4.1.2 crashes if the mode isn't initialized! - */ - attr.ia_valid = ATTR_MODE; - attr.ia_mode = S_IFLNK | S_IRWXUGO; + if (pathlen > PAGE_SIZE) + return -ENAMETOOLONG; - qsymname.name = symname; - qsymname.len = strlen(symname); + attr.ia_mode = S_IFLNK | S_IRWXUGO; + attr.ia_valid = ATTR_MODE; lock_kernel(); + + page = alloc_page(GFP_KERNEL); + if (!page) { + unlock_kernel(); + return -ENOMEM; + } + + kaddr = kmap_atomic(page, KM_USER0); + memcpy(kaddr, symname, pathlen); + if (pathlen < PAGE_SIZE) + memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen); + kunmap_atomic(kaddr, KM_USER0); + nfs_begin_data_update(dir); - error = NFS_PROTO(dir)->symlink(dir, &dentry->d_name, &qsymname, - &attr, &sym_fh, &sym_attr); + error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr); nfs_end_data_update(dir); - if (!error) { - error = nfs_instantiate(dentry, &sym_fh, &sym_attr); - } else { - if (error == -EEXIST) - printk("nfs_proc_symlink: %s/%s already exists??\n", - dentry->d_parent->d_name.name, dentry->d_name.name); + if (error != 0) { + dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n", + dir->i_sb->s_id, dir->i_ino, + dentry->d_name.name, symname, error); d_drop(dentry); + __free_page(page); + unlock_kernel(); + return error; } + + /* + * No big deal if we can't add this page to the page cache here. + * READLINK will get the missing page from the server if needed. + */ + pagevec_init(&lru_pvec, 0); + if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0, + GFP_KERNEL)) { + if (!pagevec_add(&lru_pvec, page)) + __pagevec_lru_add(&lru_pvec); + SetPageUptodate(page); + unlock_page(page); + } else + __free_page(page); + unlock_kernel(); - return error; + return 0; } static int @@ -1638,35 +1682,211 @@ out: return error; } +static DEFINE_SPINLOCK(nfs_access_lru_lock); +static LIST_HEAD(nfs_access_lru_list); +static atomic_long_t nfs_access_nr_entries; + +static void nfs_access_free_entry(struct nfs_access_entry *entry) +{ + put_rpccred(entry->cred); + kfree(entry); + smp_mb__before_atomic_dec(); + atomic_long_dec(&nfs_access_nr_entries); + smp_mb__after_atomic_dec(); +} + +int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask) +{ + LIST_HEAD(head); + struct nfs_inode *nfsi; + struct nfs_access_entry *cache; + + spin_lock(&nfs_access_lru_lock); +restart: + list_for_each_entry(nfsi, &nfs_access_lru_list, access_cache_inode_lru) { + struct inode *inode; + + if (nr_to_scan-- == 0) + break; + inode = igrab(&nfsi->vfs_inode); + if (inode == NULL) + continue; + spin_lock(&inode->i_lock); + if (list_empty(&nfsi->access_cache_entry_lru)) + goto remove_lru_entry; + cache = list_entry(nfsi->access_cache_entry_lru.next, + struct nfs_access_entry, lru); + list_move(&cache->lru, &head); + rb_erase(&cache->rb_node, &nfsi->access_cache); + if (!list_empty(&nfsi->access_cache_entry_lru)) + list_move_tail(&nfsi->access_cache_inode_lru, + &nfs_access_lru_list); + else { +remove_lru_entry: + list_del_init(&nfsi->access_cache_inode_lru); + clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags); + } + spin_unlock(&inode->i_lock); + iput(inode); + goto restart; + } + spin_unlock(&nfs_access_lru_lock); + while (!list_empty(&head)) { + cache = list_entry(head.next, struct nfs_access_entry, lru); + list_del(&cache->lru); + nfs_access_free_entry(cache); + } + return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure; +} + +static void __nfs_access_zap_cache(struct inode *inode) +{ + struct nfs_inode *nfsi = NFS_I(inode); + struct rb_root *root_node = &nfsi->access_cache; + struct rb_node *n, *dispose = NULL; + struct nfs_access_entry *entry; + + /* Unhook entries from the cache */ + while ((n = rb_first(root_node)) != NULL) { + entry = rb_entry(n, struct nfs_access_entry, rb_node); + rb_erase(n, root_node); + list_del(&entry->lru); + n->rb_left = dispose; + dispose = n; + } + nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS; + spin_unlock(&inode->i_lock); + + /* Now kill them all! */ + while (dispose != NULL) { + n = dispose; + dispose = n->rb_left; + nfs_access_free_entry(rb_entry(n, struct nfs_access_entry, rb_node)); + } +} + +void nfs_access_zap_cache(struct inode *inode) +{ + /* Remove from global LRU init */ + if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) { + spin_lock(&nfs_access_lru_lock); + list_del_init(&NFS_I(inode)->access_cache_inode_lru); + spin_unlock(&nfs_access_lru_lock); + } + + spin_lock(&inode->i_lock); + /* This will release the spinlock */ + __nfs_access_zap_cache(inode); +} + +static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred) +{ + struct rb_node *n = NFS_I(inode)->access_cache.rb_node; + struct nfs_access_entry *entry; + + while (n != NULL) { + entry = rb_entry(n, struct nfs_access_entry, rb_node); + + if (cred < entry->cred) + n = n->rb_left; + else if (cred > entry->cred) + n = n->rb_right; + else + return entry; + } + return NULL; +} + int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res) { struct nfs_inode *nfsi = NFS_I(inode); - struct nfs_access_entry *cache = &nfsi->cache_access; + struct nfs_access_entry *cache; + int err = -ENOENT; - if (cache->cred != cred - || time_after(jiffies, cache->jiffies + NFS_ATTRTIMEO(inode)) - || (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)) - return -ENOENT; - memcpy(res, cache, sizeof(*res)); - return 0; + spin_lock(&inode->i_lock); + if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS) + goto out_zap; + cache = nfs_access_search_rbtree(inode, cred); + if (cache == NULL) + goto out; + if (time_after(jiffies, cache->jiffies + NFS_ATTRTIMEO(inode))) + goto out_stale; + res->jiffies = cache->jiffies; + res->cred = cache->cred; + res->mask = cache->mask; + list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru); + err = 0; +out: + spin_unlock(&inode->i_lock); + return err; +out_stale: + rb_erase(&cache->rb_node, &nfsi->access_cache); + list_del(&cache->lru); + spin_unlock(&inode->i_lock); + nfs_access_free_entry(cache); + return -ENOENT; +out_zap: + /* This will release the spinlock */ + __nfs_access_zap_cache(inode); + return -ENOENT; } -void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set) +static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set) { struct nfs_inode *nfsi = NFS_I(inode); - struct nfs_access_entry *cache = &nfsi->cache_access; + struct rb_root *root_node = &nfsi->access_cache; + struct rb_node **p = &root_node->rb_node; + struct rb_node *parent = NULL; + struct nfs_access_entry *entry; - if (cache->cred != set->cred) { - if (cache->cred) - put_rpccred(cache->cred); - cache->cred = get_rpccred(set->cred); - } - /* FIXME: replace current access_cache BKL reliance with inode->i_lock */ spin_lock(&inode->i_lock); - nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS; + while (*p != NULL) { + parent = *p; + entry = rb_entry(parent, struct nfs_access_entry, rb_node); + + if (set->cred < entry->cred) + p = &parent->rb_left; + else if (set->cred > entry->cred) + p = &parent->rb_right; + else + goto found; + } + rb_link_node(&set->rb_node, parent, p); + rb_insert_color(&set->rb_node, root_node); + list_add_tail(&set->lru, &nfsi->access_cache_entry_lru); spin_unlock(&inode->i_lock); + return; +found: + rb_replace_node(parent, &set->rb_node, root_node); + list_add_tail(&set->lru, &nfsi->access_cache_entry_lru); + list_del(&entry->lru); + spin_unlock(&inode->i_lock); + nfs_access_free_entry(entry); +} + +void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set) +{ + struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL); + if (cache == NULL) + return; + RB_CLEAR_NODE(&cache->rb_node); cache->jiffies = set->jiffies; + cache->cred = get_rpccred(set->cred); cache->mask = set->mask; + + nfs_access_add_rbtree(inode, cache); + + /* Update accounting */ + smp_mb__before_atomic_inc(); + atomic_long_inc(&nfs_access_nr_entries); + smp_mb__after_atomic_inc(); + + /* Add inode to global LRU list */ + if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) { + spin_lock(&nfs_access_lru_lock); + list_add_tail(&NFS_I(inode)->access_cache_inode_lru, &nfs_access_lru_list); + spin_unlock(&nfs_access_lru_lock); + } } static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask) |