From: Eric Sandeen Subject: Re: [PATCH 0/4] 32/64 bit llseek hashes (v4) Date: Wed, 09 Nov 2011 08:59:29 -0600 Message-ID: <4EBA9551.4000404@redhat.com> References: <20110817095717.1879649.41075.stgit@fsdevel3> <4E5D6058.8040805@fastmail.fm> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Bernd Schubert , linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, yong.fan-KloliPT79xf2eFz/2MeuCQ@public.gmane.org, adilger-KloliPT79xf2eFz/2MeuCQ@public.gmane.org, "J. Bruce Fields" , "Ted Ts'o" To: Bernd Schubert Return-path: In-Reply-To: <4E5D6058.8040805-97jfqw80gc6171pxa8y+qA@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On 8/30/11 5:12 PM, Bernd Schubert wrote: > On 08/17/2011 11:57 AM, Bernd Schubert wrote: >> With the ext3/ext4 directory index implementation hashes are used to specify >> offsets for llseek(). For compatibility with NFSv2 and 32-bit user space >> on 64-bit systems (kernel space) ext3/ext4 currently only return 32-bit >> hashes and therefore the probability of hash collisions for larger directories >> is rather high. As recently reported on the NFS mailing list that theoretical >> problem also happens on real systems: >> http://comments.gmane.org/gmane.linux.nfs/40863 >> >> The following series adds two new f_mode flags to tell ext4 >> to use 32-bit or 64-bit hash values for llseek() calls. >> These flags can then used by network file systems, such as NFS, to >> request 32-bit or 64-bit offsets (hashes). >> >> Version 4 >> - Andreas noticed there was HAVE_IS_COMPAT_TASK instead of >> CONFIG_COMPAT in the >> "Return 32/64-bit dir name hash according to usage type" >> patch >> >> Version 3: >> - remove patch "RFC: Remove check for a 32-bit cookie in nfsd4_readdir()", >> I think Bruce wanted to take it seperately as bug fix. It should be applied >> before applying the remaining NFS patches, as without it NFSv4 will always >> fail with the new 64-bit ext4 seek hashes. >> - split "nfsd: vfs_llseek() with 32 or 64 bit offsets (hashes)" into two >> two separate patches as suggested by Bruce, one patch to rename >> 'access' to 'may_flags'. And the remainder of the original patch to set >> FMODE_32BITHASH/FMODE_64BITHASH flags and to introduce the new >> NFSD_MAY_64BIT_COOKIE flag >> >> Version 2: >> - use f_mode instead of O_* flags and also in a separate patch >> - introduce EXT4_HTREE_EOF_32BIT and EXT4_HTREE_EOF_64BIT >> - fix SEEK_END in ext4_dir_llseek() >> - set f_mode flags in NFS code as early as possible and introduce a new >> NFSD_MAY_64BIT_COOKIE flag for that >> > > Ted, > > any chance you could take this series or at least ack the ext4 part? Bruce already acked the NFS patches. > > > Acked-by: J. Bruce Fields > Ted, what is the status of these patches for ext4 at this point? -eric > > Thanks, > Bernd > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html