From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754525AbcHVEYp (ORCPT ); Mon, 22 Aug 2016 00:24:45 -0400 Received: from mail-io0-f195.google.com ([209.85.223.195]:35311 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753471AbcHVEYi (ORCPT ); Mon, 22 Aug 2016 00:24:38 -0400 From: Shaun Tancheff To: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Shaun Tancheff , Tejun Heo , Christoph Hellwig , Tom Yan , "Martin K . Petersen" , Damien Le Moal , Hannes Reinecke , Josh Bingaman , Hannes Reinecke , Shaun Tancheff Subject: [PATCH v6 1/4] libata: Safely overwrite attached page in WRITE SAME xlat Date: Sun, 21 Aug 2016 23:23:18 -0500 Message-Id: <20160822042321.24367-2-shaun@tancheff.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160822042321.24367-1-shaun@tancheff.com> References: <20160822042321.24367-1-shaun@tancheff.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Safely overwriting the attached page to ATA format from the SCSI formatted variant. Signed-off-by: Shaun Tancheff --- v6: - Fix bisect bug reported by Tom Yan - Change to use sg_copy_from_buffer as per Christoph Hellwig v5: - Added prep patch to work with non-page aligned scatterlist pages and use kmap_atomic() to lock page during modification. drivers/ata/libata-scsi.c | 56 ++++++++++++++++++++++++++++++++++++++++++----- include/linux/ata.h | 26 ---------------------- 2 files changed, 51 insertions(+), 31 deletions(-) diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index e207b33..7990cb2 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -3282,6 +3282,54 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc) return 1; } +/** + * ata_format_dsm_trim_descr() - SATL Write Same to DSM Trim + * @cmd: SCSI command being translated + * @num: Maximum number of entries (nominally 64). + * @sector: Starting sector + * @count: Total Range of request + * + * Rewrite the WRITE SAME descriptor to be a DSM TRIM little-endian formatted + * descriptor. + * + * Upto 64 entries of the format: + * 63:48 Range Length + * 47:0 LBA + * + * Range Length of 0 is ignored. + * LBA's should be sorted order and not overlap. + * + * NOTE: this is the same format as ADD LBA(S) TO NV CACHE PINNED SET + */ +static unsigned int ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 num, + u64 sector, u32 count) +{ + __le64 *buffer; + u32 i = 0, used_bytes; + unsigned long flags; + + BUILD_BUG_ON(512 > ATA_SCSI_RBUF_SIZE); + + spin_lock_irqsave(&ata_scsi_rbuf_lock, flags); + buffer = ((void *)ata_scsi_rbuf); + while (i < num) { + u64 entry = sector | + ((u64)(count > 0xffff ? 0xffff : count) << 48); + buffer[i++] = __cpu_to_le64(entry); + if (count <= 0xffff) + break; + count -= 0xffff; + sector += 0xffff; + } + + used_bytes = ALIGN(i * 8, 512); + memset(buffer + i, 0, used_bytes - i * 8); + sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buffer, 512); + spin_unlock_irqrestore(&ata_scsi_rbuf_lock, flags); + + return used_bytes; +} + static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) { struct ata_taskfile *tf = &qc->tf; @@ -3290,8 +3338,8 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) const u8 *cdb = scmd->cmnd; u64 block; u32 n_block; + const u32 trmax = ATA_MAX_TRIM_RNUM; u32 size; - void *buf; u16 fp; u8 bp = 0xff; @@ -3319,10 +3367,8 @@ static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc) if (!scsi_sg_count(scmd)) goto invalid_param_len; - buf = page_address(sg_page(scsi_sglist(scmd))); - - if (n_block <= 65535 * ATA_MAX_TRIM_RNUM) { - size = ata_set_lba_range_entries(buf, ATA_MAX_TRIM_RNUM, block, n_block); + if (n_block <= 0xffff * trmax) { + size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block); } else { fp = 2; goto invalid_fld; diff --git a/include/linux/ata.h b/include/linux/ata.h index adbc812..45a1d71 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -1071,32 +1071,6 @@ static inline void ata_id_to_hd_driveid(u16 *id) #endif } -/* - * Write LBA Range Entries to the buffer that will cover the extent from - * sector to sector + count. This is used for TRIM and for ADD LBA(S) - * TO NV CACHE PINNED SET. - */ -static inline unsigned ata_set_lba_range_entries(void *_buffer, - unsigned num, u64 sector, unsigned long count) -{ - __le64 *buffer = _buffer; - unsigned i = 0, used_bytes; - - while (i < num) { - u64 entry = sector | - ((u64)(count > 0xffff ? 0xffff : count) << 48); - buffer[i++] = __cpu_to_le64(entry); - if (count <= 0xffff) - break; - count -= 0xffff; - sector += 0xffff; - } - - used_bytes = ALIGN(i * 8, 512); - memset(buffer + i, 0, used_bytes - i * 8); - return used_bytes; -} - static inline bool ata_ok(u8 status) { return ((status & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ | ATA_ERR)) -- 2.9.3