From 7007e9dd56767a95de0947b3f7599bcc2f21687f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 5 Oct 2020 10:41:28 +0200 Subject: [PATCH] scsi: core: Clean up allocation and freeing of sgtables Rename scsi_init_io() to scsi_alloc_sgtables(), and ensure callers call scsi_free_sgtables() to cleanup failures close to scsi_init_io() instead of leaking it down the generic I/O submission path. Link: https://lore.kernel.org/r/20201005084130.143273-9-hch@lst.de Reviewed-by: Hannes Reinecke Signed-off-by: Christoph Hellwig Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_lib.c | 22 ++++++++-------------- drivers/scsi/sd.c | 27 +++++++++++++++------------ drivers/scsi/sr.c | 16 ++++++---------- include/scsi/scsi_cmnd.h | 3 ++- 4 files changed, 31 insertions(+), 37 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index a6419e4..55a1a06 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -515,7 +515,7 @@ static void scsi_uninit_cmd(struct scsi_cmnd *cmd) } } -static void scsi_free_sgtables(struct scsi_cmnd *cmd) +void scsi_free_sgtables(struct scsi_cmnd *cmd) { if (cmd->sdb.table.nents) sg_free_table_chained(&cmd->sdb.table, @@ -524,6 +524,7 @@ static void scsi_free_sgtables(struct scsi_cmnd *cmd) sg_free_table_chained(&cmd->prot_sdb->table, SCSI_INLINE_PROT_SG_CNT); } +EXPORT_SYMBOL_GPL(scsi_free_sgtables); static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) { @@ -983,7 +984,7 @@ static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev, } /** - * scsi_init_io - SCSI I/O initialization function. + * scsi_alloc_sgtables - allocate S/G tables for a command * @cmd: command descriptor we wish to initialize * * Returns: @@ -991,7 +992,7 @@ static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev, * * BLK_STS_RESOURCE - if the failure is retryable * * BLK_STS_IOERR - if the failure is fatal */ -blk_status_t scsi_init_io(struct scsi_cmnd *cmd) +blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd) { struct scsi_device *sdev = cmd->device; struct request *rq = cmd->request; @@ -1083,7 +1084,7 @@ out_free_sgtables: scsi_free_sgtables(cmd); return ret; } -EXPORT_SYMBOL(scsi_init_io); +EXPORT_SYMBOL(scsi_alloc_sgtables); /** * scsi_initialize_rq - initialize struct scsi_cmnd partially @@ -1171,7 +1172,7 @@ static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev, * submit a request without an attached bio. */ if (req->bio) { - blk_status_t ret = scsi_init_io(cmd); + blk_status_t ret = scsi_alloc_sgtables(cmd); if (unlikely(ret != BLK_STS_OK)) return ret; } else { @@ -1213,19 +1214,12 @@ static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev, struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); - blk_status_t ret; cmd->sc_data_direction = rq_dma_dir(req); if (blk_rq_is_scsi(req)) - ret = scsi_setup_scsi_cmnd(sdev, req); - else - ret = scsi_setup_fs_cmnd(sdev, req); - - if (ret != BLK_STS_OK) - scsi_free_sgtables(cmd); - - return ret; + return scsi_setup_scsi_cmnd(sdev, req); + return scsi_setup_fs_cmnd(sdev, req); } static blk_status_t diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 7aa6988..cfe59ed 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -902,7 +902,7 @@ static blk_status_t sd_setup_unmap_cmnd(struct scsi_cmnd *cmd) cmd->transfersize = data_len; rq->timeout = SD_TIMEOUT; - return scsi_init_io(cmd); + return scsi_alloc_sgtables(cmd); } static blk_status_t sd_setup_write_same16_cmnd(struct scsi_cmnd *cmd, @@ -934,7 +934,7 @@ static blk_status_t sd_setup_write_same16_cmnd(struct scsi_cmnd *cmd, cmd->transfersize = data_len; rq->timeout = unmap ? SD_TIMEOUT : SD_WRITE_SAME_TIMEOUT; - return scsi_init_io(cmd); + return scsi_alloc_sgtables(cmd); } static blk_status_t sd_setup_write_same10_cmnd(struct scsi_cmnd *cmd, @@ -966,7 +966,7 @@ static blk_status_t sd_setup_write_same10_cmnd(struct scsi_cmnd *cmd, cmd->transfersize = data_len; rq->timeout = unmap ? SD_TIMEOUT : SD_WRITE_SAME_TIMEOUT; - return scsi_init_io(cmd); + return scsi_alloc_sgtables(cmd); } static blk_status_t sd_setup_write_zeroes_cmnd(struct scsi_cmnd *cmd) @@ -1107,7 +1107,7 @@ static blk_status_t sd_setup_write_same_cmnd(struct scsi_cmnd *cmd) * knows how much to actually write. */ rq->__data_len = sdp->sector_size; - ret = scsi_init_io(cmd); + ret = scsi_alloc_sgtables(cmd); rq->__data_len = blk_rq_bytes(rq); return ret; @@ -1226,23 +1226,24 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd) unsigned int dif; bool dix; - ret = scsi_init_io(cmd); + ret = scsi_alloc_sgtables(cmd); if (ret != BLK_STS_OK) return ret; + ret = BLK_STS_IOERR; if (!scsi_device_online(sdp) || sdp->changed) { scmd_printk(KERN_ERR, cmd, "device offline or changed\n"); - return BLK_STS_IOERR; + goto fail; } if (blk_rq_pos(rq) + blk_rq_sectors(rq) > get_capacity(rq->rq_disk)) { scmd_printk(KERN_ERR, cmd, "access beyond end of device\n"); - return BLK_STS_IOERR; + goto fail; } if ((blk_rq_pos(rq) & mask) || (blk_rq_sectors(rq) & mask)) { scmd_printk(KERN_ERR, cmd, "request not aligned to the logical block size\n"); - return BLK_STS_IOERR; + goto fail; } /* @@ -1264,7 +1265,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd) if (req_op(rq) == REQ_OP_ZONE_APPEND) { ret = sd_zbc_prepare_zone_append(cmd, &lba, nr_blocks); if (ret) - return ret; + goto fail; } fua = rq->cmd_flags & REQ_FUA ? 0x8 : 0; @@ -1292,7 +1293,7 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd) } if (unlikely(ret != BLK_STS_OK)) - return ret; + goto fail; /* * We shouldn't disconnect in the middle of a sector, so with a dumb @@ -1316,10 +1317,12 @@ static blk_status_t sd_setup_read_write_cmnd(struct scsi_cmnd *cmd) blk_rq_sectors(rq))); /* - * This indicates that the command is ready from our end to be - * queued. + * This indicates that the command is ready from our end to be queued. */ return BLK_STS_OK; +fail: + scsi_free_sgtables(cmd); + return ret; } static blk_status_t sd_init_command(struct scsi_cmnd *cmd) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 0c4aa46..b74dfd8 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -392,15 +392,11 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt) struct request *rq = SCpnt->request; blk_status_t ret; - ret = scsi_init_io(SCpnt); + ret = scsi_alloc_sgtables(SCpnt); if (ret != BLK_STS_OK) - goto out; + return ret; cd = scsi_cd(rq->rq_disk); - /* from here on until we're complete, any goto out - * is used for a killable error condition */ - ret = BLK_STS_IOERR; - SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt, "Doing sr request, block = %d\n", block)); @@ -509,12 +505,12 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt) SCpnt->allowed = MAX_RETRIES; /* - * This indicates that the command is ready from our end to be - * queued. + * This indicates that the command is ready from our end to be queued. */ - ret = BLK_STS_OK; + return BLK_STS_OK; out: - return ret; + scsi_free_sgtables(SCpnt); + return BLK_STS_IOERR; } static int sr_block_open(struct block_device *bdev, fmode_t mode) diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index e76bac4..69ade4f 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -165,7 +165,8 @@ extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, size_t *offset, size_t *len); extern void scsi_kunmap_atomic_sg(void *virt); -extern blk_status_t scsi_init_io(struct scsi_cmnd *cmd); +blk_status_t scsi_alloc_sgtables(struct scsi_cmnd *cmd); +void scsi_free_sgtables(struct scsi_cmnd *cmd); #ifdef CONFIG_SCSI_DMA extern int scsi_dma_map(struct scsi_cmnd *cmd); -- 2.7.4