From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E519747DD62; Thu, 2 Jul 2026 10:04:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782986689; cv=none; b=KS9bSOZ+zTOOckSpy+ilEMporMX4kWV83jtNPnJlRQU1T8ttbT0aoxJANIpBOn3a3GifYsvYI1ZapLwHAcmVSa+ZBrD+NMaiqlPrldMpzlSr8kuNk8vLogrpGcrNrPMVi2aui6uQDvClfr31TtBAoHs7+nRqzZ7f5qC4kxu20Ns= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782986689; c=relaxed/simple; bh=L6oSNd7GV2jSHo+ihp6kJpgSCebZhaMLZbUN60878YM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nranW1GWdzQuV5jWqR9+RacVh2ZghOJhXlX2trVd3UYQipN9VNQlhtjExUlye3MorQnekAoUvZwZxT0rpoX3x9AJPe+3dPxGzHTV7WqPfSFnj2Uc7RpVfX2Z75Nf+AJqzktolLWahFdlr4oH3nsWH0pSFAgJuHFEV/vVB1kblCM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HxDuEocg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HxDuEocg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2DC1E1F000E9; Thu, 2 Jul 2026 10:04:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782986687; bh=7MolXIuFQCcEw6yux0O93RhUgjvcHpLOfWblU4nHW8I=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HxDuEocgJ3cV0esalapJsMfCJ/kiZWX9cVhDXlDGWQ0SR0vF6ws8LmpClIDUtyMh3 Ex9APq6eEKQSCPIqd2NyNB/TvV6tD1GUve4U9Rf5o4b/GM3DOWEr2SiAXahg55jANW NnYgsm2zHWsZMkrWeL6Rn+Hr7ZEIuYywI3z7CXD/hwx79FuMvKHcHoRqkjMYDlVeyf hyxQQw4yCbDsfhW2uUkfMgQr5ui8NvP9/JGddpaWPvTdfxPhNRdycMIdvG3I7BK+m9 CrL9QwCqJZwkZfesnncX1BIR5O9ctRNafvKK64cxS7PM2WFjzeXdWZZ+J4e1NpOi3z 7Qzo7iXrcAxDQ== From: Niklas Cassel To: Damien Le Moal , Niklas Cassel , Shaun Tancheff , Tejun Heo Cc: Hannes Reinecke , stable@vger.kernel.org, linux-ide@vger.kernel.org Subject: [PATCH v2 1/2] ata: libata-scsi: fix DSM TRIM for sector sizes larger than 2048 bytes Date: Thu, 2 Jul 2026 12:04:12 +0200 Message-ID: <20260702100410.2039383-5-cassel@kernel.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260702100410.2039383-4-cassel@kernel.org> References: <20260702100410.2039383-4-cassel@kernel.org> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=4442; i=cassel@kernel.org; h=from:subject; bh=L6oSNd7GV2jSHo+ihp6kJpgSCebZhaMLZbUN60878YM=; b=owGbwMvMwCV2MsVw8cxjvkWMp9WSGLLczOf/ZVd4avNSMGLeiZCDpVtWs0Xur3DOydJ+vuZE8 EnmAy/iO0pZGMS4GGTFFFl8f7jsL+52n3Jc8Y4NzBxWJpAhDFycAjARPWuG/4FZ0a762o15b/7q rXiYurlwwi+ro4pPSjWLCuZM22aw+jDDX6nLTX7+CpPO3zGcbqP1+fnqVrdb4gfcdqT+nfal739 kPRcA X-Developer-Key: i=cassel@kernel.org; a=openpgp; fpr=5ADE635C0E631CBBD5BE065A352FE6582ED9B5DA Content-Transfer-Encoding: 8bit ata_scsi_write_same_xlat() translates a SCSI WRITE SAME command with the UNMAP bit set into an ATA DATA SET MANAGEMENT TRIM command. The TRIM descriptor is built by ata_format_dsm_trim_descr() into the 2048-byte ata_scsi_rbuf staging buffer, and the number of bytes copied is compared against the logical sector size by the caller: size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block); if (size != len) /* len == sdp->sector_size */ goto invalid_param_len; ata_format_dsm_trim_descr() clamps the copy length to ATA_SCSI_RBUF_SIZE (2048). On a device whose logical sector size exceeds that (e.g. a 4Kn device, where sector_size == 4096) the function can never return more than 2048, while the caller expects it to return sector_size. The comparison therefore always fails, so every TRIM is rejected with "Parameter list length error" and WARN_ON() splats on each attempt. TRIM / discard is thus completely broken on such devices. The descriptor was incorrectly sized from the logical sector size. A DSM TRIM payload is a list of 512-byte pages, each holding up to ATA_MAX_TRIM_RNUM (64) LBA Range Entries, and is independent of the logical sector size. The Block Limits VPD page already advertises a single such page as the maximum WRITE SAME length (65535 * ATA_MAX_TRIM_RNUM logical blocks), so the block layer never sends a request that needs more than one page. Emit exactly one 512-byte page, independent of the logical sector size, and transfer only that page (COUNT == 1). For a 512-byte-sector device this is unchanged; devices with larger logical sectors now work instead of failing every TRIM. Reviewed-by: Hannes Reinecke Fixes: ef2d7392c4ec ("libata: SCT Write Same / DSM Trim") Cc: stable@vger.kernel.org Signed-off-by: Niklas Cassel --- drivers/ata/libata-scsi.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index d54ec1631e9a..429b03a08071 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -3447,17 +3447,13 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc) static size_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax, u64 sector, u32 count) { - struct scsi_device *sdp = cmd->device; - size_t len = sdp->sector_size; + size_t len = ATA_SECT_SIZE; size_t r; __le64 *buf; u32 i = 0; unsigned long flags; - WARN_ON(len > ATA_SCSI_RBUF_SIZE); - - if (len > ATA_SCSI_RBUF_SIZE) - len = ATA_SCSI_RBUF_SIZE; + BUILD_BUG_ON(ATA_SECT_SIZE > ATA_SCSI_RBUF_SIZE); spin_lock_irqsave(&ata_scsi_rbuf_lock, flags); buf = ((void *)ata_scsi_rbuf); @@ -3492,13 +3488,11 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) { struct ata_taskfile *tf = &qc->tf; struct scsi_cmnd *scmd = qc->scsicmd; - struct scsi_device *sdp = scmd->device; - size_t len = sdp->sector_size; struct ata_device *dev = qc->dev; const u8 *cdb = scmd->cmnd; u64 block; u32 n_block; - const u32 trmax = len >> 3; + const u32 trmax = ATA_MAX_TRIM_RNUM; u32 size; u16 fp; u8 bp = 0xff; @@ -3542,13 +3536,13 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) goto invalid_param_len; /* - * size must match sector size in bytes - * For DATA SET MANAGEMENT TRIM in ACS-2 nsect (aka count) - * is defined as number of 512 byte blocks to be transferred. + * The TRIM descriptor is a single 512-byte page, which is the maximum + * WRITE SAME length advertised in the Block Limits VPD page. For DATA + * SET MANAGEMENT TRIM the COUNT field (aka nsect) is the number of + * 512-byte blocks to be transferred. */ - size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block); - if (size != len) + if (size != ATA_SECT_SIZE) goto invalid_param_len; if (ata_ncq_enabled(dev) && ata_fpdma_dsm_supported(dev)) { @@ -3574,6 +3568,12 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) ATA_TFLAG_WRITE; ata_qc_set_pc_nbytes(qc); + /* + * The DSM TRIM payload is a single 512-byte page, which may be smaller + * than the WRITE SAME data-out buffer (one logical block); only + * transfer that page so the length matches the COUNT field. + */ + qc->nbytes = size; return 0; -- 2.55.0