From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from aserp1040.oracle.com ([141.146.126.69]:39938 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753033AbdJSTNE (ORCPT ); Thu, 19 Oct 2017 15:13:04 -0400 Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id v9JJD3wN026021 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 19 Oct 2017 19:13:03 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id v9JJD3MI008890 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK) for ; Thu, 19 Oct 2017 19:13:03 GMT Received: from abhmp0013.oracle.com (abhmp0013.oracle.com [141.146.116.19]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id v9JJD3vo017623 for ; Thu, 19 Oct 2017 19:13:03 GMT Date: Thu, 19 Oct 2017 12:13:01 -0700 From: "Darrick J. Wong" Subject: Re: [PATCH 03/17] Add xfs_attr_set_defered and xfs_attr_remove_defered Message-ID: <20171019191301.GD4755@magnolia> References: <1508367333-3237-1-git-send-email-allison.henderson@oracle.com> <1508367333-3237-4-git-send-email-allison.henderson@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1508367333-3237-4-git-send-email-allison.henderson@oracle.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Allison Henderson Cc: linux-xfs@vger.kernel.org On Wed, Oct 18, 2017 at 03:55:19PM -0700, Allison Henderson wrote: > These routines set up set and start a new deferred attribute > operation. These functions are meant to be called by other > code needing to initiate a deferred attribute operation. We > will use these routines later in the parent pointer patches. > > Signed-off-by: Allison Henderson > --- > fs/xfs/libxfs/xfs_attr.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++ > fs/xfs/xfs_attr.h | 7 ++++++ > 2 files changed, 65 insertions(+) > > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > index 5325ec2..59f3502 100644 > --- a/fs/xfs/libxfs/xfs_attr.c > +++ b/fs/xfs/libxfs/xfs_attr.c > @@ -458,6 +458,37 @@ xfs_attr_set( > return error; > } > > +int > +xfs_attr_set_deferred( > + struct xfs_inode *dp, > + struct xfs_defer_ops *dfops, > + const unsigned char *name, > + unsigned int namelen, > + unsigned char *value, > + unsigned int valuelen, > + int flags) > +{ > + > + struct xfs_attr_item *new; > + > + ASSERT(namelen != 0); > + ASSERT(valuelen != 0); > + > + new = kmem_alloc(sizeof(struct xfs_attr_item), KM_SLEEP|KM_NOFS); Yikes, this is a 66,000 byte allocation. I wouldn't take it for granted that we can ask for more than a page's worth of memory. Seeing as we already know namelen and valuelen, let's go for the zero length array at the end of the struct approach: struct xfs_attr_item { ... uint16_t xattri_namelen; uint8_t xattri_namevalue[0]; }; #define XFS_ATTR_ITEM_SIZEOF(namelen, valuelen) \ (sizeof(struct xfs_attr_item) + (namelen) + (valuelen)) new = kmem_alloc(XFS_ATTR_ITEM_SIZEOF(namelen, valuelen), KM...); if (!new) return -ENOMEM; memcpy(new->xattri_namevalue, name, namelen); new->xattri_namelen = namelen; memcpy(&new->xattri_namevalue[namelen], value, valuelen); ... Assuming there isn't a way to attach the caller's buffers to the attr item without copying anything(?) (It would be nice if we could, but between the defer_add and the defer_finish a lot can happen w.r.t. variable scope so that might be a bad idea.) > + memset(new, 0, sizeof(struct xfs_attr_item)); > + new->xattri_ino = dp->i_ino; > + new->xattri_op_flags = ATTR_OP_FLAGS_SET; > + new->xattri_name_len = namelen; > + new->xattri_value_len = valuelen; > + new->xattri_flags = flags; > + memcpy(new->xattri_name, name, namelen); > + memcpy(&new->xattri_value, value, valuelen); > + > + xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_ATTR, &new->xattri_list); > + > + return 0; > +} > + > /* > * Generic handler routine to remove a name from an attribute list. > * Transitions attribute list from Btree to shortform as necessary. > @@ -531,6 +562,33 @@ xfs_attr_remove( > return error; > } > > +int > +xfs_attr_remove_deferred( > + struct xfs_inode *dp, > + struct xfs_defer_ops *dfops, > + const unsigned char *name, > + unsigned int namelen, > + int flags) > +{ > + > + struct xfs_attr_item *new; > + > + ASSERT(namelen != 0); > + > + new = kmem_alloc(sizeof(struct xfs_attr_item), KM_SLEEP|KM_NOFS); > + memset(new, 0, sizeof(struct xfs_attr_item)); > + new->xattri_ino = dp->i_ino; > + new->xattri_op_flags = ATTR_OP_FLAGS_REMOVE; > + new->xattri_name_len = namelen; > + new->xattri_value_len = 0; > + new->xattri_flags = flags; > + memcpy(new->xattri_name, name, namelen); > + > + xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_ATTR, &new->xattri_list); > + > + return 0; > +} > + > /*======================================================================== > * External routines when attribute list is inside the inode > *========================================================================*/ > diff --git a/fs/xfs/xfs_attr.h b/fs/xfs/xfs_attr.h > index 34bb4cb..f4a53fd 100644 > --- a/fs/xfs/xfs_attr.h > +++ b/fs/xfs/xfs_attr.h > @@ -173,5 +173,12 @@ int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize, > int xfs_attr_args_init(struct xfs_da_args *args, struct xfs_inode *dp, > const unsigned char *name, int flags); > int xfs_attr_calc_size(struct xfs_da_args *args, int *local); > +int xfs_attr_set_deferred(struct xfs_inode *dp, struct xfs_defer_ops *dfops, > + const unsigned char *name, unsigned int name_len, > + unsigned char *value, unsigned int valuelen, > + int flags); > +int xfs_attr_remove_deferred(struct xfs_inode *dp, struct xfs_defer_ops *dfops, > + const unsigned char *name, unsigned int namelen, > + int flags); > > #endif /* __XFS_ATTR_H__ */ > -- > 2.7.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html