From: Herbert Xu Subject: Re: [PATCH] crypto: allow to assign gfp_t for __crypto_alloc_tfm Date: Tue, 19 May 2015 14:32:11 +0800 Message-ID: <20150519063211.GA28347@gondor.apana.org.au> References: <1432014416-39326-1-git-send-email-jaegeuk@kernel.org> <20150519054945.GA28060@gondor.apana.org.au> <20150519062430.GA39588@jaegeuk-mac02.hsd1.ca.comcast.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: davem@davemloft.net, linux-crypto@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, ecryptfs@vger.kernel.org, linux-arm-kernel@lists.infradead.org To: Jaegeuk Kim Return-path: Content-Disposition: inline In-Reply-To: <20150519062430.GA39588@jaegeuk-mac02.hsd1.ca.comcast.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Mon, May 18, 2015 at 11:24:30PM -0700, Jaegeuk Kim wrote: > > The call path in fs/ext4/crypto.c is: > - writepage > - ext4_encrypt > - ext4_get_crypto_ctx > - crypto_alloc_ablkcipher > > AFAIK, this way can achieve to reduce memory footprint gracefully. > Just before submitting bios, fs allocates the required memory, and then end_io > will free them in pair. So where does the key get generated? The crypto tfm should be allocated when you generate the key. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt