From e8e17ea64a9e85348b5bc4e3fefd5bf31787df4b Mon Sep 17 00:00:00 2001 From: "Matthew R. Ochs" Date: Fri, 7 Jul 2017 13:05:25 -0300 Subject: [PATCH] scsi: cxlflash: Remove port configuration assumptions BugLink: http://bugs.launchpad.net/bugs/1702521 At present, the cxlflash driver only supports hardware with two FC ports. The code was initially designed with this assumption and is dependent on having two FC ports - adding more ports will break logic within the driver. To mitigate this issue, remove the existing port assumptions and transition the code to support more than two ports. As a side effect, clarify the interpretation of the DK_CXLFLASH_ALL_PORTS_ACTIVE flag. Signed-off-by: Matthew R. Ochs Signed-off-by: Uma Krishnan Signed-off-by: Martin K. Petersen (cherry picked from commit 8fa4f1770d56af6f0a5a862f1fd298a4eeea94f3) Signed-off-by: Victor Aoqui Acked-by: Stefan Bader Acked-by: Seth Forshee Signed-off-by: Thadeu Lima de Souza Cascardo --- Documentation/powerpc/cxlflash.txt | 5 ++ drivers/scsi/cxlflash/common.h | 4 ++ drivers/scsi/cxlflash/lunmgt.c | 4 +- drivers/scsi/cxlflash/main.c | 13 ++--- drivers/scsi/cxlflash/sislite.h | 2 +- drivers/scsi/cxlflash/superpipe.c | 2 +- drivers/scsi/cxlflash/superpipe.h | 3 - drivers/scsi/cxlflash/vlun.c | 89 +++++++++++++++++++----------- 8 files changed, 77 insertions(+), 45 deletions(-) diff --git a/Documentation/powerpc/cxlflash.txt b/Documentation/powerpc/cxlflash.txt index 6d9a2ed32cad..66b4496d6619 100644 --- a/Documentation/powerpc/cxlflash.txt +++ b/Documentation/powerpc/cxlflash.txt @@ -239,6 +239,11 @@ DK_CXLFLASH_USER_VIRTUAL resource handle that is provided is already referencing provisioned storage. This is reflected by the last LBA being a non-zero value. + When a LUN is accessible from more than one port, this ioctl will + return with the DK_CXLFLASH_ALL_PORTS_ACTIVE return flag set. This + provides the user with a hint that I/O can be retried in the event + of an I/O error as the LUN can be reached over multiple paths. + DK_CXLFLASH_VLUN_RESIZE ----------------------- This ioctl is responsible for resizing a previously created virtual diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h index 6a04867a0eec..ee23e81994c4 100644 --- a/drivers/scsi/cxlflash/common.h +++ b/drivers/scsi/cxlflash/common.h @@ -29,6 +29,10 @@ extern const struct file_operations cxlflash_cxl_fops; #define NUM_FC_PORTS CXLFLASH_NUM_FC_PORTS /* ports per AFU */ #define MAX_FC_PORTS CXLFLASH_MAX_FC_PORTS /* ports per AFU */ +#define CHAN2PORTMASK(_x) (1 << (_x)) /* channel to port mask */ +#define PORTMASK2CHAN(_x) (ilog2((_x))) /* port mask to channel */ +#define PORTNUM2CHAN(_x) ((_x) - 1) /* port number to channel */ + #define CXLFLASH_BLOCK_SIZE 4096 /* 4K blocks */ #define CXLFLASH_MAX_XFER_SIZE 16777216 /* 16MB transfer */ #define CXLFLASH_MAX_SECTORS (CXLFLASH_MAX_XFER_SIZE/512) /* SCSI wants diff --git a/drivers/scsi/cxlflash/lunmgt.c b/drivers/scsi/cxlflash/lunmgt.c index 0efed177cc8b..4d232e271af6 100644 --- a/drivers/scsi/cxlflash/lunmgt.c +++ b/drivers/scsi/cxlflash/lunmgt.c @@ -252,7 +252,7 @@ int cxlflash_manage_lun(struct scsi_device *sdev, * in unpacked, AFU-friendly format, and hang LUN reference in * the sdev. */ - lli->port_sel |= CHAN2PORT(chan); + lli->port_sel |= CHAN2PORTMASK(chan); lli->lun_id[chan] = lun_to_lunid(sdev->lun); sdev->hostdata = lli; } else if (flags & DK_CXLFLASH_MANAGE_LUN_DISABLE_SUPERPIPE) { @@ -264,7 +264,7 @@ int cxlflash_manage_lun(struct scsi_device *sdev, * tracking when no more references exist. */ sdev->hostdata = NULL; - lli->port_sel &= ~CHAN2PORT(chan); + lli->port_sel &= ~CHAN2PORTMASK(chan); if (lli->port_sel == 0U) lli->in_table = false; } diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 3f9c8690af0d..04e1a8effa76 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -365,7 +365,6 @@ static int wait_resp(struct afu *afu, struct afu_cmd *cmd) */ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) { - u32 port_sel = scp->device->channel + 1; struct cxlflash_cfg *cfg = shost_priv(scp->device->host); struct afu_cmd *cmd = sc_to_afucz(scp); struct device *dev = &cfg->dev->dev; @@ -388,7 +387,7 @@ static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) cmd->rcb.ctx_id = afu->ctx_hndl; cmd->rcb.msi = SISL_MSI_RRQ_UPDATED; - cmd->rcb.port_sel = port_sel; + cmd->rcb.port_sel = CHAN2PORTMASK(scp->device->channel); cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID | SISL_REQ_FLAGS_SUP_UNDERRUN | @@ -444,7 +443,6 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) struct device *dev = &cfg->dev->dev; struct afu_cmd *cmd = sc_to_afucz(scp); struct scatterlist *sg = scsi_sglist(scp); - u32 port_sel = scp->device->channel + 1; u16 req_flags = SISL_REQ_FLAGS_SUP_UNDERRUN; ulong lock_flags; int nseg = 0; @@ -503,7 +501,7 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) cmd->rcb.ctx_id = afu->ctx_hndl; cmd->rcb.msi = SISL_MSI_RRQ_UPDATED; - cmd->rcb.port_sel = port_sel; + cmd->rcb.port_sel = CHAN2PORTMASK(scp->device->channel); cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); if (scp->sc_data_direction == DMA_TO_DEVICE) @@ -1558,7 +1556,8 @@ static int init_global(struct cxlflash_cfg *cfg) writeq_be(PORT0, &afu->afu_map->global.regs.afu_port_sel); num_ports = 0; } else { - writeq_be(BOTH_PORTS, &afu->afu_map->global.regs.afu_port_sel); + writeq_be(PORT_MASK(cfg->num_fc_ports), + &afu->afu_map->global.regs.afu_port_sel); num_ports = cfg->num_fc_ports; } @@ -2190,7 +2189,7 @@ static ssize_t lun_mode_store(struct device *dev, if (afu->internal_lun) shost->max_channel = 0; else - shost->max_channel = cfg->num_fc_ports - 1; + shost->max_channel = PORTNUM2CHAN(cfg->num_fc_ports); afu_reset(cfg); scsi_scan_host(cfg->host); @@ -2529,7 +2528,7 @@ static int cxlflash_probe(struct pci_dev *pdev, host->max_id = CXLFLASH_MAX_NUM_TARGETS_PER_BUS; host->max_lun = CXLFLASH_MAX_NUM_LUNS_PER_TARGET; - host->max_channel = NUM_FC_PORTS - 1; + host->max_channel = PORTNUM2CHAN(NUM_FC_PORTS); host->unique_id = host->host_no; host->max_cmd_len = CXLFLASH_MAX_CDB_LEN; diff --git a/drivers/scsi/cxlflash/sislite.h b/drivers/scsi/cxlflash/sislite.h index 0db4bc1f4e23..f26f41be5efb 100644 --- a/drivers/scsi/cxlflash/sislite.h +++ b/drivers/scsi/cxlflash/sislite.h @@ -479,7 +479,7 @@ struct sisl_rht_entry_f1 { #define PORT0 0x01U #define PORT1 0x02U -#define BOTH_PORTS (PORT0 | PORT1) +#define PORT_MASK(_n) ((1 << (_n)) - 1) /* AFU Sync Mode byte */ #define AFU_LW_SYNC 0x0U diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c index 90869cee2b20..488330ffdf02 100644 --- a/drivers/scsi/cxlflash/superpipe.c +++ b/drivers/scsi/cxlflash/superpipe.c @@ -1935,7 +1935,7 @@ static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg) u64 lun_size = 0; u64 last_lba = 0; u64 rsrc_handle = -1; - u32 port = CHAN2PORT(sdev->channel); + u32 port = CHAN2PORTMASK(sdev->channel); int rc = 0; diff --git a/drivers/scsi/cxlflash/superpipe.h b/drivers/scsi/cxlflash/superpipe.h index 690ce9c652b2..8269ff854bbe 100644 --- a/drivers/scsi/cxlflash/superpipe.h +++ b/drivers/scsi/cxlflash/superpipe.h @@ -33,9 +33,6 @@ extern struct cxlflash_global global; #define MAX_SECTOR_UNIT 512 /* max_sector is in 512 byte multiples */ -#define CHAN2PORT(_x) ((_x) + 1) -#define PORT2CHAN(_x) ((_x) - 1) - enum lun_mode { MODE_NONE = 0, MODE_VIRTUAL, diff --git a/drivers/scsi/cxlflash/vlun.c b/drivers/scsi/cxlflash/vlun.c index 8fcc804dbef9..547c8ffac205 100644 --- a/drivers/scsi/cxlflash/vlun.c +++ b/drivers/scsi/cxlflash/vlun.c @@ -819,8 +819,8 @@ int cxlflash_vlun_resize(struct scsi_device *sdev, void cxlflash_restore_luntable(struct cxlflash_cfg *cfg) { struct llun_info *lli, *temp; - u32 chan; u32 lind; + int k; struct afu *afu = cfg->afu; struct device *dev = &cfg->dev->dev; struct sisl_global_map __iomem *agm = &afu->afu_map->global; @@ -832,33 +832,41 @@ void cxlflash_restore_luntable(struct cxlflash_cfg *cfg) continue; lind = lli->lun_index; + dev_dbg(dev, "%s: Virtual LUNs on slot %d:\n", __func__, lind); - if (lli->port_sel == BOTH_PORTS) { - writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]); - writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]); - dev_dbg(dev, "%s: Virtual LUN on slot %d id0=%llx " - "id1=%llx\n", __func__, lind, - lli->lun_id[0], lli->lun_id[1]); - } else { - chan = PORT2CHAN(lli->port_sel); - writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]); - dev_dbg(dev, "%s: Virtual LUN on slot %d chan=%d " - "id=%llx\n", __func__, lind, chan, - lli->lun_id[chan]); - } + for (k = 0; k < cfg->num_fc_ports; k++) + if (lli->port_sel & (1 << k)) { + writeq_be(lli->lun_id[k], + &agm->fc_port[k][lind]); + dev_dbg(dev, "\t%d=%llx\n", k, lli->lun_id[k]); + } } mutex_unlock(&global.mutex); } +/** + * get_num_ports() - compute number of ports from port selection mask + * @psm: Port selection mask. + * + * Return: Population count of port selection mask + */ +static inline u8 get_num_ports(u32 psm) +{ + static const u8 bits[16] = { 0, 1, 1, 2, 1, 2, 2, 3, + 1, 2, 2, 3, 2, 3, 3, 4 }; + + return bits[psm & 0xf]; +} + /** * init_luntable() - write an entry in the LUN table * @cfg: Internal structure associated with the host. * @lli: Per adapter LUN information structure. * - * On successful return, a LUN table entry is created. - * At the top for LUNs visible on both ports. - * At the bottom for LUNs visible only on one port. + * On successful return, a LUN table entry is created: + * - at the top for LUNs visible on multiple ports. + * - at the bottom for LUNs visible only on one port. * * Return: 0 on success, -errno on failure */ @@ -866,7 +874,9 @@ static int init_luntable(struct cxlflash_cfg *cfg, struct llun_info *lli) { u32 chan; u32 lind; + u32 nports; int rc = 0; + int k; struct afu *afu = cfg->afu; struct device *dev = &cfg->dev->dev; struct sisl_global_map __iomem *agm = &afu->afu_map->global; @@ -876,29 +886,46 @@ static int init_luntable(struct cxlflash_cfg *cfg, struct llun_info *lli) if (lli->in_table) goto out; - if (lli->port_sel == BOTH_PORTS) { + nports = get_num_ports(lli->port_sel); + if (nports == 0 || nports > cfg->num_fc_ports) { + WARN(1, "Unsupported port configuration nports=%u", nports); + rc = -EIO; + goto out; + } + + if (nports > 1) { /* - * If this LUN is visible from both ports, we will put + * When LUN is visible from multiple ports, we will put * it in the top half of the LUN table. */ - if ((cfg->promote_lun_index == cfg->last_lun_index[0]) || - (cfg->promote_lun_index == cfg->last_lun_index[1])) { - rc = -ENOSPC; - goto out; + for (k = 0; k < cfg->num_fc_ports; k++) { + if (!(lli->port_sel & (1 << k))) + continue; + + if (cfg->promote_lun_index == cfg->last_lun_index[k]) { + rc = -ENOSPC; + goto out; + } } lind = lli->lun_index = cfg->promote_lun_index; - writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]); - writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]); + dev_dbg(dev, "%s: Virtual LUNs on slot %d:\n", __func__, lind); + + for (k = 0; k < cfg->num_fc_ports; k++) { + if (!(lli->port_sel & (1 << k))) + continue; + + writeq_be(lli->lun_id[k], &agm->fc_port[k][lind]); + dev_dbg(dev, "\t%d=%llx\n", k, lli->lun_id[k]); + } + cfg->promote_lun_index++; - dev_dbg(dev, "%s: Virtual LUN on slot %d id0=%llx id1=%llx\n", - __func__, lind, lli->lun_id[0], lli->lun_id[1]); } else { /* - * If this LUN is visible only from one port, we will put + * When LUN is visible only from one port, we will put * it in the bottom half of the LUN table. */ - chan = PORT2CHAN(lli->port_sel); + chan = PORTMASK2CHAN(lli->port_sel); if (cfg->promote_lun_index == cfg->last_lun_index[chan]) { rc = -ENOSPC; goto out; @@ -907,7 +934,7 @@ static int init_luntable(struct cxlflash_cfg *cfg, struct llun_info *lli) lind = lli->lun_index = cfg->last_lun_index[chan]; writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]); cfg->last_lun_index[chan]--; - dev_dbg(dev, "%s: Virtual LUN on slot %d chan=%d id=%llx\n", + dev_dbg(dev, "%s: Virtual LUNs on slot %d:\n\t%d=%llx\n", __func__, lind, chan, lli->lun_id[chan]); } @@ -1016,7 +1043,7 @@ int cxlflash_disk_virtual_open(struct scsi_device *sdev, void *arg) virt->last_lba = last_lba; virt->rsrc_handle = rsrc_handle; - if (lli->port_sel == BOTH_PORTS) + if (get_num_ports(lli->port_sel) > 1) virt->hdr.return_flags |= DK_CXLFLASH_ALL_PORTS_ACTIVE; out: if (likely(ctxi)) -- 2.39.2