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De Francesco" X-Patchwork-Id: 13070655 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE979C4167B for ; Sun, 11 Dec 2022 21:31:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230186AbiLKVbX (ORCPT ); Sun, 11 Dec 2022 16:31:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230031AbiLKVbW (ORCPT ); Sun, 11 Dec 2022 16:31:22 -0500 Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4BD7ADE93; Sun, 11 Dec 2022 13:31:21 -0800 (PST) Received: by mail-wm1-x336.google.com with SMTP id f13-20020a1cc90d000000b003d08c4cf679so3631074wmb.5; Sun, 11 Dec 2022 13:31:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=iT8jy7hXGuLdSI3WnW19MAFpxEEAB5GqxCDkyx7KpM4=; b=bHIaQoWiU/RqdS0GRKzMghm5tUXLJ+904G799bZNyECaA+xGQUUX5VrxuxK60g4z1n ngvtGi9jl+kCHdtgF0pR7EywnsK79hRXBKqaeJB7YvykSu+dv3RGDRBDup5d+lIuKe3/ B+3y71WOzZdUAnsPbvB6H4Fndjt0fS/VtB1i37X3gr896cbtSB+Qxi2unLBTDyxx6UcC F5mzvNnVp3c/baEZLDKJKe4KKn3YpB8VlNJs0i5ZCxfwqT+1oDdT12CFjm+pxWPckD8M cAUtAtvKLgwtxI0Q1IO2y0ezzQ0OJpGi5mBU6ghnuvBKIM8TOToMwV0KANPkWM42kE62 macw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=iT8jy7hXGuLdSI3WnW19MAFpxEEAB5GqxCDkyx7KpM4=; b=0juqYqG7XVTesbxuRUg9S87e5Nza6+NxJw6jykgZKYwQZpwAes1nJugVw6Oa13H6Ar Vz9vaYciAoL1o/Czciw4/gViDw3qXkybQiPuR1as2p30BfEFwyEkTxSUs1cVjEWFUhZ9 N1UIaaLpWfvyU2t9ZRNIidZxdF50HfFmuG8EXprPWMFjyi2aP/QK8KKoNj1eql7QcOF9 ccCdLDpjyL8Hh8wfZNWwfuK3t+nItDw8LUFe2yF7cjOydgnnhoTyVRjWE43thwi9OAxW a98OIma1XsQ7yOgnlBH0O9M6wLqSxOndINnL9ujbtqwiCjAntpLMH8tlNDFmss0rpzet Otig== X-Gm-Message-State: ANoB5pmMx6BEumNACpGgKgySa7RAAx9pkCNo7l1+Dc+qLjbRqkeQuXg3 uaWNZ7mE/oDDb/saZhf8K70= X-Google-Smtp-Source: AA0mqf5zWAFa4VcpAunSbDQqJ17B48IWR0tqfODzum12dcsBaja0xsp9d+A8KtyFeJosx1va5PbGOw== X-Received: by 2002:a05:600c:3584:b0:3d1:bf7c:391c with SMTP id p4-20020a05600c358400b003d1bf7c391cmr10228233wmq.4.1670794279732; Sun, 11 Dec 2022 13:31:19 -0800 (PST) Received: from localhost.localdomain (host-95-247-100-134.retail.telecomitalia.it. [95.247.100.134]) by smtp.gmail.com with ESMTPSA id m127-20020a1c2685000000b003d1d5a83b2esm6866350wmm.35.2022.12.11.13.31.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 11 Dec 2022 13:31:19 -0800 (PST) From: "Fabio M. De Francesco" To: Evgeniy Dushistov , Al Viro , Ira Weiny , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: "Fabio M. De Francesco" Subject: [PATCH 1/3] fs/ufs: Use the offset_in_page() helper Date: Sun, 11 Dec 2022 22:31:09 +0100 Message-Id: <20221211213111.30085-2-fmdefrancesco@gmail.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221211213111.30085-1-fmdefrancesco@gmail.com> References: <20221211213111.30085-1-fmdefrancesco@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Use the offset_in_page() helper because it is more suitable than doing explicit subtractions between pointers to directory entries and kernel virtual addresses of mapped pages. Cc: Ira Weiny Suggested-by: Al Viro Signed-off-by: Fabio M. De Francesco --- fs/ufs/dir.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c index 391efaf1d528..69f78583c9c1 100644 --- a/fs/ufs/dir.c +++ b/fs/ufs/dir.c @@ -87,8 +87,7 @@ void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de, struct page *page, struct inode *inode, bool update_times) { - loff_t pos = page_offset(page) + - (char *) de - (char *) page_address(page); + loff_t pos = page_offset(page) + offset_in_page(de); unsigned len = fs16_to_cpu(dir->i_sb, de->d_reclen); int err; @@ -371,8 +370,7 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode) return -EINVAL; got_it: - pos = page_offset(page) + - (char*)de - (char*)page_address(page); + pos = page_offset(page) + offset_in_page(de); err = ufs_prepare_chunk(page, pos, rec_len); if (err) goto out_unlock; @@ -497,8 +495,8 @@ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, { struct super_block *sb = inode->i_sb; char *kaddr = page_address(page); - unsigned from = ((char*)dir - kaddr) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); - unsigned to = ((char*)dir - kaddr) + fs16_to_cpu(sb, dir->d_reclen); + unsigned int from = offset_in_page(dir) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); + unsigned int to = offset_in_page(dir) + fs16_to_cpu(sb, dir->d_reclen); loff_t pos; struct ufs_dir_entry *pde = NULL; struct ufs_dir_entry *de = (struct ufs_dir_entry *) (kaddr + from); @@ -522,7 +520,7 @@ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, de = ufs_next_entry(sb, de); } if (pde) - from = (char*)pde - (char*)page_address(page); + from = offset_in_page(pde); pos = page_offset(page) + from; lock_page(page); From patchwork Sun Dec 11 21:31:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Fabio M. De Francesco" X-Patchwork-Id: 13070657 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2285C10F31 for ; Sun, 11 Dec 2022 21:31:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230322AbiLKVb2 (ORCPT ); Sun, 11 Dec 2022 16:31:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43650 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230319AbiLKVb1 (ORCPT ); Sun, 11 Dec 2022 16:31:27 -0500 Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B896FBC99; Sun, 11 Dec 2022 13:31:22 -0800 (PST) Received: by mail-wm1-x32f.google.com with SMTP id ja4-20020a05600c556400b003cf6e77f89cso8565765wmb.0; Sun, 11 Dec 2022 13:31:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=xO4/ERMIN9nZq44yFlvMqRszu/PsYtiiSWLF6dQbDKM=; b=emEK43fXCYtt0QOkugug9uHbdapiTHrNAxtcEWvYoNQGWhuSZnEd4TR7z2ITdOAAud Gp8SA8r1M/CdoknWxd8+Lg7X09IuWtpT8hAGrciRbkX6aZIYQv6jxfnzZvf8CyMs3jPP pv12GmWfDJAbFJGJI34m9YlswEd5KdiIP29RF8eMF+nlC7Ziu38S2dSPQ1eqAsKMXSYC R5IqTgCQeEHK3rxG5uvgDmwUP0n/5p6TMurISJH8nrtipeXwflu6L4Ab3/Js/R7W63mm xIgPsgwtmSBzMMfkxKdbTg/qdPLIswK7E9A7CSb9oeLT2uMQlftNPSt5GNSfo/9Kqlf7 sQjA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=xO4/ERMIN9nZq44yFlvMqRszu/PsYtiiSWLF6dQbDKM=; b=GZjzYd50+9W8wPoUnC+ncOLFose53WTiDGuf/KltJZRL90CxcplU7LQy8XG4VMWQ8A TEvqMRNVjPoMZCvkmbdYWcN8yWWAsdI3qiKfZGHlNOPc9N2LCkhgWV9lH5qENjM/dW8S MRfNS8s2bQ5humz8yL2y7ia67j31+y4GJcCJRnbZiPTtTDZusLnOa3CggEpzFxX3HowX U0AjcPL7aGAfHZvsBUPtpfWiTVQOrQEzSHjHFb3o2ITlQzYtisrdg975BU7N8mxba3gT q39cJq80/BMfGQv828x1ZPGyxF/cSe9po85y4NcJmaUQD3v/AbAWAHMXda/a2VxQ/Vh4 OEtw== X-Gm-Message-State: ANoB5pkxwcH2ZxLTr8HvIs8vxzWfacvJlZADgI+I5m4AfFvFsE0l/vlc HI5swqNMvp6DjptiDvianHwA5iVgBPs= X-Google-Smtp-Source: AA0mqf5ihx4Q3YPN5I2Y9XxUAf6J9EFqWmBBkwpx33fAjG+z+QhZK13KI9X2/heFqtSRr9Nsk2LR8Q== X-Received: by 2002:a05:600c:a54:b0:3cf:894f:964b with SMTP id c20-20020a05600c0a5400b003cf894f964bmr10646599wmq.16.1670794281261; Sun, 11 Dec 2022 13:31:21 -0800 (PST) Received: from localhost.localdomain (host-95-247-100-134.retail.telecomitalia.it. [95.247.100.134]) by smtp.gmail.com with ESMTPSA id m127-20020a1c2685000000b003d1d5a83b2esm6866350wmm.35.2022.12.11.13.31.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 11 Dec 2022 13:31:20 -0800 (PST) From: "Fabio M. De Francesco" To: Evgeniy Dushistov , Al Viro , Ira Weiny , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: "Fabio M. De Francesco" Subject: [PATCH 2/3] fs/ufs: Change the signature of ufs_get_page() Date: Sun, 11 Dec 2022 22:31:10 +0100 Message-Id: <20221211213111.30085-3-fmdefrancesco@gmail.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221211213111.30085-1-fmdefrancesco@gmail.com> References: <20221211213111.30085-1-fmdefrancesco@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Change the signature of ufs_get_page() in order to prepare this function to the conversion to the use of kmap_local_page(). Change also those call sites which are required to conform its invocations to the new signature. Cc: Ira Weiny Suggested-by: Al Viro Signed-off-by: Fabio M. De Francesco --- fs/ufs/dir.c | 58 ++++++++++++++++++++++------------------------------ 1 file changed, 24 insertions(+), 34 deletions(-) diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c index 69f78583c9c1..bb6b29ce1d3a 100644 --- a/fs/ufs/dir.c +++ b/fs/ufs/dir.c @@ -185,21 +185,21 @@ static bool ufs_check_page(struct page *page) return false; } -static struct page *ufs_get_page(struct inode *dir, unsigned long n) +static void *ufs_get_page(struct inode *dir, unsigned long n, struct page **page) { struct address_space *mapping = dir->i_mapping; - struct page *page = read_mapping_page(mapping, n, NULL); - if (!IS_ERR(page)) { - kmap(page); - if (unlikely(!PageChecked(page))) { - if (!ufs_check_page(page)) + *page = read_mapping_page(mapping, n, NULL); + if (!IS_ERR(*page)) { + kmap(*page); + if (unlikely(!PageChecked(*page))) { + if (!ufs_check_page(*page)) goto fail; } } return page; fail: - ufs_put_page(page); + ufs_put_page(*page); return ERR_PTR(-EIO); } @@ -227,15 +227,12 @@ ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p) struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p) { - struct page *page = ufs_get_page(dir, 0); - struct ufs_dir_entry *de = NULL; + struct ufs_dir_entry *de = ufs_get_page(dir, 0, p); - if (!IS_ERR(page)) { - de = ufs_next_entry(dir->i_sb, - (struct ufs_dir_entry *)page_address(page)); - *p = page; - } - return de; + if (!IS_ERR(de)) + return ufs_next_entry(dir->i_sb, de); + else + return NULL; } /* @@ -273,11 +270,10 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr, start = 0; n = start; do { - char *kaddr; - page = ufs_get_page(dir, n); - if (!IS_ERR(page)) { - kaddr = page_address(page); - de = (struct ufs_dir_entry *) kaddr; + char *kaddr = ufs_get_page(dir, n, &page); + + if (!IS_ERR(kaddr)) { + de = (struct ufs_dir_entry *)kaddr; kaddr += ufs_last_byte(dir, n) - reclen; while ((char *) de <= kaddr) { if (ufs_match(sb, namelen, name, de)) @@ -328,12 +324,10 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode) for (n = 0; n <= npages; n++) { char *dir_end; - page = ufs_get_page(dir, n); - err = PTR_ERR(page); - if (IS_ERR(page)) - goto out; + kaddr = ufs_get_page(dir, n, &page); + if (IS_ERR(kaddr)) + return PTR_ERR(kaddr); lock_page(page); - kaddr = page_address(page); dir_end = kaddr + ufs_last_byte(dir, n); de = (struct ufs_dir_entry *)kaddr; kaddr += PAGE_SIZE - reclen; @@ -395,8 +389,6 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode) /* OFFSET_CACHE */ out_put: ufs_put_page(page); -out: - return err; out_unlock: unlock_page(page); goto out_put; @@ -429,6 +421,7 @@ ufs_readdir(struct file *file, struct dir_context *ctx) unsigned chunk_mask = ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); bool need_revalidate = !inode_eq_iversion(inode, file->f_version); unsigned flags = UFS_SB(sb)->s_flags; + struct page *page; UFSD("BEGIN\n"); @@ -439,16 +432,14 @@ ufs_readdir(struct file *file, struct dir_context *ctx) char *kaddr, *limit; struct ufs_dir_entry *de; - struct page *page = ufs_get_page(inode, n); - - if (IS_ERR(page)) { + kaddr = ufs_get_page(inode, n, &page); + if (IS_ERR(kaddr)) { ufs_error(sb, __func__, "bad page in #%lu", inode->i_ino); ctx->pos += PAGE_SIZE - offset; return -EIO; } - kaddr = page_address(page); if (unlikely(need_revalidate)) { if (offset) { offset = ufs_validate_entry(sb, kaddr, offset, chunk_mask); @@ -595,12 +586,11 @@ int ufs_empty_dir(struct inode * inode) for (i = 0; i < npages; i++) { char *kaddr; struct ufs_dir_entry *de; - page = ufs_get_page(inode, i); - if (IS_ERR(page)) + kaddr = ufs_get_page(inode, i, &page); + if (IS_ERR(kaddr)) continue; - kaddr = page_address(page); de = (struct ufs_dir_entry *)kaddr; kaddr += ufs_last_byte(inode, i) - UFS_DIR_REC_LEN(1); From patchwork Sun Dec 11 21:31:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Fabio M. 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[95.247.100.134]) by smtp.gmail.com with ESMTPSA id m127-20020a1c2685000000b003d1d5a83b2esm6866350wmm.35.2022.12.11.13.31.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 11 Dec 2022 13:31:22 -0800 (PST) From: "Fabio M. De Francesco" To: Evgeniy Dushistov , Al Viro , Ira Weiny , linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: "Fabio M. De Francesco" Subject: [PATCH 3/3] fs/ufs: Replace kmap() with kmap_local_page() Date: Sun, 11 Dec 2022 22:31:11 +0100 Message-Id: <20221211213111.30085-4-fmdefrancesco@gmail.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221211213111.30085-1-fmdefrancesco@gmail.com> References: <20221211213111.30085-1-fmdefrancesco@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org kmap() is being deprecated in favor of kmap_local_page(). There are two main problems with kmap(): (1) It comes with an overhead as the mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. Furthermore, the tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and still valid. Since its use in fs/ufs is safe everywhere, it should be preferred. Therefore, replace kmap() with kmap_local_page() in fs/ufs. kunmap_local() requires the mapping address, so return that address from ufs_get_page() to be used in ufs_put_page(). Suggested-by: Al Viro Suggested-by: Ira Weiny Signed-off-by: Fabio M. De Francesco --- fs/ufs/dir.c | 76 ++++++++++++++++++++++++++++++++-------------------- 1 file changed, 47 insertions(+), 29 deletions(-) diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c index bb6b29ce1d3a..fd57d8171c88 100644 --- a/fs/ufs/dir.c +++ b/fs/ufs/dir.c @@ -61,9 +61,9 @@ static int ufs_commit_chunk(struct page *page, loff_t pos, unsigned len) return err; } -static inline void ufs_put_page(struct page *page) +static inline void ufs_put_page(struct page *page, void *page_addr) { - kunmap(page); + kunmap((void *)((unsigned long)page_addr & PAGE_MASK)); put_page(page); } @@ -76,7 +76,7 @@ ino_t ufs_inode_by_name(struct inode *dir, const struct qstr *qstr) de = ufs_find_entry(dir, qstr, &page); if (de) { res = fs32_to_cpu(dir->i_sb, de->d_ino); - ufs_put_page(page); + ufs_put_page(page, de); } return res; } @@ -99,18 +99,17 @@ void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de, ufs_set_de_type(dir->i_sb, de, inode->i_mode); err = ufs_commit_chunk(page, pos, len); - ufs_put_page(page); + ufs_put_page(page, de); if (update_times) dir->i_mtime = dir->i_ctime = current_time(dir); mark_inode_dirty(dir); } -static bool ufs_check_page(struct page *page) +static bool ufs_check_page(struct page *page, char *kaddr) { struct inode *dir = page->mapping->host; struct super_block *sb = dir->i_sb; - char *kaddr = page_address(page); unsigned offs, rec_len; unsigned limit = PAGE_SIZE; const unsigned chunk_mask = UFS_SB(sb)->s_uspi->s_dirblksize - 1; @@ -185,21 +184,30 @@ static bool ufs_check_page(struct page *page) return false; } +/* + * Calls to ufs_get_page()/ufs_put_page() must be nested according to the + * rules documented in kmap_local_page()/kunmap_local(). + * + * NOTE: ufs_find_entry() and ufs_dotdot() act as calls to ufs_get_page() + * and must be treated accordingly for nesting purposes. + */ static void *ufs_get_page(struct inode *dir, unsigned long n, struct page **page) { + char *kaddr; + struct address_space *mapping = dir->i_mapping; *page = read_mapping_page(mapping, n, NULL); if (!IS_ERR(*page)) { - kmap(*page); + kmap_local_page(*page); if (unlikely(!PageChecked(*page))) { - if (!ufs_check_page(*page)) + if (!ufs_check_page(*page, kaddr)) goto fail; } } - return page; + return *page; fail: - ufs_put_page(*page); + ufs_put_page(*page, kaddr); return ERR_PTR(-EIO); } @@ -225,6 +233,13 @@ ufs_next_entry(struct super_block *sb, struct ufs_dir_entry *p) fs16_to_cpu(sb, p->d_reclen)); } +/* + * Calls to ufs_get_page()/ufs_put_page() must be nested according to the + * rules documented in kmap_local_page()/kunmap_local(). + * + * ufs_dotdot() acts as a call to ufs_get_page() and must be treated + * accordingly for nesting purposes. + */ struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p) { struct ufs_dir_entry *de = ufs_get_page(dir, 0, p); @@ -236,12 +251,15 @@ struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct page **p) } /* - * ufs_find_entry() + * Finds an entry in the specified directory with the wanted name. It returns a + * pointer to the directory's entry. The page in which the entry was found is + * in the res_page out parameter. The page is returned mapped and unlocked. + * The entry is guaranteed to be valid. + * + * On Success ufs_put_page() should be called on *res_page. * - * finds an entry in the specified directory with the wanted name. It - * returns the page in which the entry was found, and the entry itself - * (as a parameter - res_dir). Page is returned mapped and unlocked. - * Entry is guaranteed to be valid. + * ufs_find_entry() acts as a call to ufs_get_page() and must be treated + * accordingly for nesting purposes. */ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr, struct page **res_page) @@ -280,7 +298,7 @@ struct ufs_dir_entry *ufs_find_entry(struct inode *dir, const struct qstr *qstr, goto found; de = ufs_next_entry(sb, de); } - ufs_put_page(page); + ufs_put_page(page, kaddr); } if (++n >= npages) n = 0; @@ -358,7 +376,7 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode) de = (struct ufs_dir_entry *) ((char *) de + rec_len); } unlock_page(page); - ufs_put_page(page); + ufs_put_page(page, kaddr); } BUG(); return -EINVAL; @@ -388,7 +406,8 @@ int ufs_add_link(struct dentry *dentry, struct inode *inode) mark_inode_dirty(dir); /* OFFSET_CACHE */ out_put: - ufs_put_page(page); + ufs_put_page(page, kaddr); + return 0; out_unlock: unlock_page(page); goto out_put; @@ -465,13 +484,13 @@ ufs_readdir(struct file *file, struct dir_context *ctx) ufs_get_de_namlen(sb, de), fs32_to_cpu(sb, de->d_ino), d_type)) { - ufs_put_page(page); + ufs_put_page(page, kaddr); return 0; } } ctx->pos += fs16_to_cpu(sb, de->d_reclen); } - ufs_put_page(page); + ufs_put_page(page, kaddr); } return 0; } @@ -482,10 +501,10 @@ ufs_readdir(struct file *file, struct dir_context *ctx) * previous entry. */ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, - struct page * page) + struct page *page) { struct super_block *sb = inode->i_sb; - char *kaddr = page_address(page); + char *kaddr = (char *)((unsigned long)dir & PAGE_MASK); unsigned int from = offset_in_page(dir) & ~(UFS_SB(sb)->s_uspi->s_dirblksize - 1); unsigned int to = offset_in_page(dir) + fs16_to_cpu(sb, dir->d_reclen); loff_t pos; @@ -524,7 +543,7 @@ int ufs_delete_entry(struct inode *inode, struct ufs_dir_entry *dir, inode->i_ctime = inode->i_mtime = current_time(inode); mark_inode_dirty(inode); out: - ufs_put_page(page); + ufs_put_page(page, kaddr); UFSD("EXIT\n"); return err; } @@ -548,8 +567,7 @@ int ufs_make_empty(struct inode * inode, struct inode *dir) goto fail; } - kmap(page); - base = (char*)page_address(page); + base = kmap_local_page(page); memset(base, 0, PAGE_SIZE); de = (struct ufs_dir_entry *) base; @@ -566,7 +584,7 @@ int ufs_make_empty(struct inode * inode, struct inode *dir) de->d_reclen = cpu_to_fs16(sb, chunk_size - UFS_DIR_REC_LEN(1)); ufs_set_de_namlen(sb, de, 2); strcpy (de->d_name, ".."); - kunmap(page); + kunmap_local(base); err = ufs_commit_chunk(page, 0, chunk_size); fail: @@ -582,9 +600,9 @@ int ufs_empty_dir(struct inode * inode) struct super_block *sb = inode->i_sb; struct page *page = NULL; unsigned long i, npages = dir_pages(inode); + char *kaddr; for (i = 0; i < npages; i++) { - char *kaddr; struct ufs_dir_entry *de; kaddr = ufs_get_page(inode, i, &page); @@ -617,12 +635,12 @@ int ufs_empty_dir(struct inode * inode) } de = ufs_next_entry(sb, de); } - ufs_put_page(page); + ufs_put_page(page, kaddr); } return 1; not_empty: - ufs_put_page(page); + ufs_put_page(page, kaddr); return 0; }