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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KO1DNZyx4YD5RtjukEtl6CNJDiiUE3YTSudRfT7usFDyEg4WDiiFCNUp8SXj?= =?us-ascii?Q?+RIIeGUs1MCZhQQ0houL9ogl5TZL+SP1FUc/mBmkghnS/No4KE9IOMCJnWUk?= =?us-ascii?Q?igvva1UGFoc4jQt7Uk0HYVdjWmqdmFC0owPK6V7sNuewEy4WaKfPAns7GQPI?= =?us-ascii?Q?6myadd9nRnf00WECPZzKTtoTAM76/8kVoAE0fBtsblUjzRI/v6AG9sG76soV?= =?us-ascii?Q?LU+n+VyQgmd7Nm1R3uVv75voxL4XrGi6f2ALSQvj+i7x8dmJ19Up+gF81wvX?= =?us-ascii?Q?qPeXRONEDnh4zvRtLsvpzegpCLKOLP1jV4HrMWV8Ta2fLEcZZyxUoOiW46ci?= =?us-ascii?Q?oj4ZJVBi98m+1LSIu2wsy3CCygq0gVqzGJR8nmKn+tuz+lY1evpuFkjysE+y?= =?us-ascii?Q?NNIUdaC59aZSa86HW+x7Lcr7IFmCQPvYe57GJOz9BRcuTOSSonpDHwvmWmSC?= =?us-ascii?Q?d6wSzbzmmx+nd08VJf9tvhL8nm+ok66SMX5OmQnqCF1oHLay6USo3kyFzBVl?= =?us-ascii?Q?qIiCaOzcNLJj7nd2kQnRVpgJX8VikS3Qn0C98IJMSUAYrCEa596MYyY21aAI?= =?us-ascii?Q?pFrdbJ8qkxF8EHxt+UYy06HKUiwxAnHI6DcZzWnBchhnp9G42PYec/lTtHoK?= =?us-ascii?Q?fxFluQN9KCA4WFEmN9pOjBlpqlYPawhaWSEaqW4aVEUM9poR2q9ghGRvEVmN?= =?us-ascii?Q?0Ysky841y19gHT1K55ZrmxuGGol/hDsQ6Q7gnYqXfU6fn5eBdJEukrN5vZbk?= =?us-ascii?Q?E4Bed+o/osPgqazvK2aYX3t2rIudqnJxt2x1PuAfITf9hq4yKDl/KhibgdvX?= =?us-ascii?Q?yc1m2k80FrmK+HeBYbcmGAqMIL8YeoAbEyCKDUsXaC5RSEMvZmRpfVijH1z6?= =?us-ascii?Q?4gLOsetlc2LNo8NEFSeFKtRVoxdV1yelg6V2slOYyHy2zVGxkl8jB7GJoZv3?= =?us-ascii?Q?VgEllMZ9kzS2y/D/crzVRLIv6m5a77Csp5EVdd0/2lP4BbTqk+Eel8cVWkFr?= =?us-ascii?Q?EduOeMeQjV7cxTEmSmgFHwbz9qEm7g0WlHphK+34mObeNGKG36vcBofyg9uQ?= =?us-ascii?Q?U2V76k2W31F412jyezlwV2HriPpFGsD9Sx1UJ8fh7pCwv3+NyCCKsn6Lw/tn?= =?us-ascii?Q?vgLJBjHiiS8mO9Z3lUy13nChtZnAKHin5Or6KTQVRqXC3YU3RRQ7oGU0wly8?= =?us-ascii?Q?cN/Vt87/f3wHhMfZFIajYcjoy3m9qtMOaQ1mZun5/grnr5mXppmqzfC6PVWu?= =?us-ascii?Q?Rf3oymuNa0No+6IP7dneiLCpDV8nwLVe9skFMK99Ajuqu5s+1u0W1rzTewgV?= =?us-ascii?Q?0nRynkUGMfaM2BCLVpTSQHtOBAE/r0saacQxrps/LpnMvnUo4kUpWeDfNYAl?= =?us-ascii?Q?7+VGwjqZUpjbVCTSyqR71OOlFqHqRa6rFbeJubkSyHRQhenJsCgz+bT7B5Mj?= =?us-ascii?Q?TVhzBakQUoFZ46mImlkamTx2XzMf1s70dZ4g38RmK3+FOn/1FeAq2gnxyjXG?= =?us-ascii?Q?6oOIDrxGmiitjvDqzC4NrsUa8reth7ZaDZ06ky+/CBg5hoI9ErMLRHW36SuF?= =?us-ascii?Q?TL6Jm0d1doTVfAxs+tHWfUYOyNZdWu0je4Jd98R+?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b80f43a-cfff-48c9-c3ec-08de335802f2 X-MS-Exchange-CrossTenant-AuthSource: DU2PR04MB8951.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Dec 2025 17:10:28.4838 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: qqDx/nkEJHsphxfq75Pg2au403r/aLByWoS22aBLUYdJTqFaQ/so9hShRfxEMrTyAyW1NI6sv4D0s9wRstyAkw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV2PR04MB11374 On Wed, Dec 03, 2025 at 11:39:21AM +0100, Niklas Cassel wrote: > On Wed, Dec 03, 2025 at 05:40:45PM +0900, Koichiro Den wrote: > > > > > > If we want to improve the dw-edma driver, so that an EPF driver can have > > > multiple outstanding transfers, I think the best way forward would be to create > > > a new _prep_slave_memcpy() or similar, that does take a direction, and thus > > > does not require dmaengine_slave_config() to be called before every > > > _prep_slave_memcpy() call. > > > > Would dmaengine_prep_slave_single_config(), which Frank tolds us in this > > thread, be sufficient? > > I think that Frank is suggesting a new dmaengine API, > dmaengine_prep_slave_single_config(), which is like > dmaengine_prep_slave_single(), but also takes a struct dma_slave_config * > as a parameter. > > > I really like the idea. > I think it would allow us to remove the mutex in nvmet_pci_epf_dma_transfer(): > https://github.com/torvalds/linux/blob/v6.18/drivers/nvme/target/pci-epf.c#L389-L429 > > Frank you wrote: "Thanks, we also consider ..." > Does that mean that you have any plans to work on this? > I would definitely be interested. Great, let me draft one version, I am seeking enough user case, which can really reduce code or enough benenfit. Frank > > > Kind regards, > Niklas