Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938754AbZDJH3l (ORCPT ); Fri, 10 Apr 2009 03:29:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S938118AbZDJHSs (ORCPT ); Fri, 10 Apr 2009 03:18:48 -0400 Received: from mfbichi11.ns.itscom.net ([219.110.2.189]:61587 "EHLO mfbichi11.ns.itscom.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938120AbZDJHSe (ORCPT ); Fri, 10 Apr 2009 03:18:34 -0400 From: "J. R. Okajima" To: linux-kernel@vger.kernel.org Cc: greg@kroah.com, linux-fsdevel@vger.kernel.org, "J. R. Okajima" Subject: [RFC Aufs2 #5 10/29] aufs sub-dcache Date: Fri, 10 Apr 2009 16:02:24 +0900 Message-Id: <1239346963-30953-11-git-send-email-hooanon05@yahoo.co.jp> X-Mailer: git-send-email 1.6.1.284.g5dc13 In-Reply-To: <1239346963-30953-1-git-send-email-hooanon05@yahoo.co.jp> References: <1239346963-30953-1-git-send-email-hooanon05@yahoo.co.jp> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7020 Lines: 288 initial commit sub-routines or simple wrappers for dentry cache Signed-off-by: J. R. Okajima --- fs/aufs/dcsub.c | 214 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/aufs/dcsub.h | 43 +++++++++++ 2 files changed, 257 insertions(+), 0 deletions(-) create mode 100644 fs/aufs/dcsub.c create mode 100644 fs/aufs/dcsub.h diff --git a/fs/aufs/dcsub.c b/fs/aufs/dcsub.c new file mode 100644 index 0000000..e4597e4 --- /dev/null +++ b/fs/aufs/dcsub.c @@ -0,0 +1,214 @@ +/* + * Copyright (C) 2005-2009 Junjiro R. Okajima + * + * This program, aufs is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +/* + * sub-routines for dentry cache + */ + +#include "aufs.h" + +static void au_dpage_free(struct au_dpage *dpage) +{ + int i; + struct dentry **p; + + p = dpage->dentries; + for (i = 0; i < dpage->ndentry; i++) + dput(*p++); + free_page((unsigned long)dpage->dentries); +} + +int au_dpages_init(struct au_dcsub_pages *dpages, gfp_t gfp) +{ + int err; + void *p; + + err = -ENOMEM; + dpages->dpages = kmalloc(sizeof(*dpages->dpages), gfp); + if (unlikely(!dpages->dpages)) + goto out; + + p = (void *)__get_free_page(gfp); + if (unlikely(!p)) + goto out_dpages; + + dpages->dpages[0].ndentry = 0; + dpages->dpages[0].dentries = p; + dpages->ndpage = 1; + return 0; /* success */ + + out_dpages: + kfree(dpages->dpages); + out: + return err; +} + +void au_dpages_free(struct au_dcsub_pages *dpages) +{ + int i; + struct au_dpage *p; + + p = dpages->dpages; + for (i = 0; i < dpages->ndpage; i++) + au_dpage_free(p++); + kfree(dpages->dpages); +} + +static int au_dpages_append(struct au_dcsub_pages *dpages, + struct dentry *dentry, gfp_t gfp) +{ + int err, sz; + struct au_dpage *dpage; + void *p; + + dpage = dpages->dpages + dpages->ndpage - 1; + sz = PAGE_SIZE / sizeof(dentry); + if (unlikely(dpage->ndentry >= sz)) { + AuLabel(new dpage); + err = -ENOMEM; + sz = dpages->ndpage * sizeof(*dpages->dpages); + p = au_kzrealloc(dpages->dpages, sz, + sz + sizeof(*dpages->dpages), gfp); + if (unlikely(!p)) + goto out; + + dpages->dpages = p; + dpage = dpages->dpages + dpages->ndpage; + p = (void *)__get_free_page(gfp); + if (unlikely(!p)) + goto out; + + dpage->ndentry = 0; + dpage->dentries = p; + dpages->ndpage++; + } + + dpage->dentries[dpage->ndentry++] = dget(dentry); + return 0; /* success */ + + out: + return err; +} + +int au_dcsub_pages(struct au_dcsub_pages *dpages, struct dentry *root, + au_dpages_test test, void *arg) +{ + int err; + struct dentry *this_parent = root; + struct list_head *next; + struct super_block *sb = root->d_sb; + + err = 0; + spin_lock(&dcache_lock); + repeat: + next = this_parent->d_subdirs.next; + resume: + if (this_parent->d_sb == sb + && !IS_ROOT(this_parent) + && atomic_read(&this_parent->d_count) + && this_parent->d_inode + && (!test || test(this_parent, arg))) { + err = au_dpages_append(dpages, this_parent, GFP_ATOMIC); + if (unlikely(err)) + goto out; + } + + while (next != &this_parent->d_subdirs) { + struct list_head *tmp = next; + struct dentry *dentry = list_entry(tmp, struct dentry, + d_u.d_child); + next = tmp->next; + if (/*d_unhashed(dentry) || */!dentry->d_inode) + continue; + if (!list_empty(&dentry->d_subdirs)) { + this_parent = dentry; + goto repeat; + } + if (dentry->d_sb == sb + && atomic_read(&dentry->d_count) + && (!test || test(dentry, arg))) { + err = au_dpages_append(dpages, dentry, GFP_ATOMIC); + if (unlikely(err)) + goto out; + } + } + + if (this_parent != root) { + next = this_parent->d_u.d_child.next; + this_parent = this_parent->d_parent; /* dcache_lock is locked */ + goto resume; + } + out: + spin_unlock(&dcache_lock); + return err; +} + +int au_dcsub_pages_rev(struct au_dcsub_pages *dpages, struct dentry *dentry, + int do_include, au_dpages_test test, void *arg) +{ + int err; + + err = 0; + spin_lock(&dcache_lock); + if (do_include && (!test || test(dentry, arg))) { + err = au_dpages_append(dpages, dentry, GFP_ATOMIC); + if (unlikely(err)) + goto out; + } + while (!IS_ROOT(dentry)) { + dentry = dentry->d_parent; /* dcache_lock is locked */ + if (!test || test(dentry, arg)) { + err = au_dpages_append(dpages, dentry, GFP_ATOMIC); + if (unlikely(err)) + break; + } + } + + out: + spin_unlock(&dcache_lock); + + return err; +} + +struct dentry *au_test_subdir(struct dentry *d1, struct dentry *d2) +{ + struct dentry *trap, **dentries; + int err, i, j; + struct au_dcsub_pages dpages; + struct au_dpage *dpage; + + trap = ERR_PTR(-ENOMEM); + err = au_dpages_init(&dpages, GFP_NOFS); + if (unlikely(err)) + goto out; + err = au_dcsub_pages_rev(&dpages, d1, /*do_include*/1, NULL, NULL); + if (unlikely(err)) + goto out_dpages; + + trap = d1; + for (i = 0; !err && i < dpages.ndpage; i++) { + dpage = dpages.dpages + i; + dentries = dpage->dentries; + for (j = 0; !err && j < dpage->ndentry; j++) { + struct dentry *d; + + d = dentries[j]; + err = (d == d2); + if (!err) + trap = d; + } + } + if (!err) + trap = NULL; + + out_dpages: + au_dpages_free(&dpages); + out: + return trap; +} diff --git a/fs/aufs/dcsub.h b/fs/aufs/dcsub.h new file mode 100644 index 0000000..89a7745 --- /dev/null +++ b/fs/aufs/dcsub.h @@ -0,0 +1,43 @@ +/* + * Copyright (C) 2005-2009 Junjiro R. Okajima + * + * This program, aufs is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +/* + * sub-routines for dentry cache + */ + +#ifndef __AUFS_DCSUB_H__ +#define __AUFS_DCSUB_H__ + +#ifdef __KERNEL__ + +#include + +struct au_dpage { + int ndentry; + struct dentry **dentries; +}; + +struct au_dcsub_pages { + int ndpage; + struct au_dpage *dpages; +}; + +/* ---------------------------------------------------------------------- */ + +int au_dpages_init(struct au_dcsub_pages *dpages, gfp_t gfp); +void au_dpages_free(struct au_dcsub_pages *dpages); +typedef int (*au_dpages_test)(struct dentry *dentry, void *arg); +int au_dcsub_pages(struct au_dcsub_pages *dpages, struct dentry *root, + au_dpages_test test, void *arg); +int au_dcsub_pages_rev(struct au_dcsub_pages *dpages, struct dentry *dentry, + int do_include, au_dpages_test test, void *arg); +struct dentry *au_test_subdir(struct dentry *d1, struct dentry *d2); + +#endif /* __KERNEL__ */ +#endif /* __AUFS_DCSUB_H__ */ -- 1.6.1.284.g5dc13 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/