Re: [PATCH v9 08/13] lpfc: vmid: Functions to manage vmids
From: Hannes Reinecke <hare@suse.de>
Date: 2021-04-08 08:36:00
Also in:
linux-nvme, linux-scsi
On 4/7/21 1:06 AM, Muneendra wrote:
quoted hunk ↗ jump to hunk
From: Gaurav Srivastava <redacted> This patch contains the routines to save, retrieve and remove the vmids from the data structure. A hash table is used to save the vmids and the corresponding UUIDs associated with the application/VMs. Signed-off-by: Gaurav Srivastava <redacted> Signed-off-by: James Smart <redacted> --- v9: Added changes for implementing kernel based hashtable v8: Added correct return value and error codes v7: No change v6: Added Forward declarations and functions to static v5: Changed Return code to non-numeric/Symbol v4: No change v3: No change v2: Ported the patch on top of 5.10/scsi-queue --- drivers/scsi/lpfc/lpfc_scsi.c | 118 ++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+)diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c index 0868cb38d5b0..f81178464436 100644 --- a/drivers/scsi/lpfc/lpfc_scsi.c +++ b/drivers/scsi/lpfc/lpfc_scsi.c@@ -28,6 +28,7 @@ #include <asm/unaligned.h> #include <linux/t10-pi.h> #include <linux/crc-t10dif.h> +#include <linux/blk-cgroup.h> #include <net/checksum.h> #include <scsi/scsi.h>@@ -86,6 +87,14 @@ static void lpfc_release_scsi_buf_s3(struct lpfc_hba *phba, struct lpfc_io_buf *psb); static int lpfc_prot_group_type(struct lpfc_hba *phba, struct scsi_cmnd *sc); +static void +lpfc_put_vmid_in_hashtable(struct lpfc_vport *vport, u32 hash, + struct lpfc_vmid *vmp); +static void lpfc_vmid_update_entry(struct lpfc_vport *vport, struct scsi_cmnd + *cmd, struct lpfc_vmid *vmp, + union lpfc_vmid_io_tag *tag); +static void lpfc_vmid_assign_cs_ctl(struct lpfc_vport *vport, + struct lpfc_vmid *vmid); static inline unsigned lpfc_cmd_blksize(struct scsi_cmnd *sc)@@ -5145,6 +5154,115 @@ void lpfc_poll_timeout(struct timer_list *t) } } +/* + * lpfc_get_vmid_from_hastable - search the UUID in the hash table + * @vport: The virtual port for which this call is being executed. + * @hash: calculated hash value + * @buf: uuid associated with the VE + * Returns the vmid entry associated with the UUID + * Make sure to acquire the appropriate lock before invoking this routine. + */ +struct lpfc_vmid *lpfc_get_vmid_from_hastable(struct lpfc_vport *vport, + u32 hash, u8 *buf)
lpfc_get_vmid_from_hashtable(), please.
+{
+ struct lpfc_vmid *vmp;
+
+ hash_for_each_possible(vport->hash_table, vmp, hnode, hash) {
+ if (memcmp(&vmp->host_vmid[0], buf, 16) == 0)
+ return vmp;
+ }
+ return NULL;
+}
+
+/*
+ * lpfc_put_vmid_from_hastable - put the VMID in the hash table
+ * @vport: The virtual port for which this call is being executed.
+ * @hash - calculated hash value
+ * @vmp: Pointer to a VMID entry representing a VM sending IO
+ *
+ * This routine will insert the newly acquired vmid entity in the hash table.
+ * Make sure to acquire the appropriate lock before invoking this routine.
+ */
+static void
+lpfc_put_vmid_in_hashtable(struct lpfc_vport *vport, u32 hash,
+ struct lpfc_vmid *vmp)
+{
+ hash_add(vport->hash_table, &vmp->hnode, hash);
+}
+Similar here; lpfc_put_vmid_in_hashtable()
+/*
+ * lpfc_vmid_hash_fn - creates a hash value of the UUID
+ * @vmid: uuid associated with the VE
+ * @len: length of the vmid string
+ * Returns the calculated hash value
+ */
+int lpfc_vmid_hash_fn(const char *vmid, int len)
+{
+ int c;
+ int hash = 0;
+
+ if (len == 0)
+ return 0;
+ while (len--) {
+ c = *vmid++;
+ if (c >= 'A' && c <= 'Z')
+ c += 'a' - 'A';
+
+ hash = (hash + (c << LPFC_VMID_HASH_SHIFT) +
+ (c >> LPFC_VMID_HASH_SHIFT)) * 19;
+ }
+
+ return hash & LPFC_VMID_HASH_MASK;
+}
+
+/*
+ * lpfc_vmid_update_entry - update the vmid entry in the hash table
+ * @vport: The virtual port for which this call is being executed.
+ * @cmd: address of scsi cmmd descriptor
+ * @vmp: Pointer to a VMID entry representing a VM sending IO
+ * @tag: VMID tag
+ */
+static void lpfc_vmid_update_entry(struct lpfc_vport *vport, struct scsi_cmnd
+ *cmd, struct lpfc_vmid *vmp,
+ union lpfc_vmid_io_tag *tag)
+{
+ u64 *lta;
+
+ if (vport->vmid_priority_tagging)
+ tag->cs_ctl_vmid = vmp->un.cs_ctl_vmid;
+ else
+ tag->app_id = vmp->un.app_id;
+
+ if (cmd->sc_data_direction == DMA_TO_DEVICE)
+ vmp->io_wr_cnt++;
+ else
+ vmp->io_rd_cnt++;
+
+ /* update the last access timestamp in the table */
+ lta = per_cpu_ptr(vmp->last_io_time, raw_smp_processor_id());
+ *lta = jiffies;
+}
+
+static void lpfc_vmid_assign_cs_ctl(struct lpfc_vport *vport,
+ struct lpfc_vmid *vmid)
+{
+ u32 hash;
+ struct lpfc_vmid *pvmid;
+
+ if (vport->port_type == LPFC_PHYSICAL_PORT) {
+ vmid->un.cs_ctl_vmid = lpfc_vmid_get_cs_ctl(vport);
+ } else {
+ hash = lpfc_vmid_hash_fn(vmid->host_vmid, vmid->vmid_len);
+ pvmid =
+ lpfc_get_vmid_from_hastable(vport->phba->pport, hash,
+ vmid->host_vmid);
+ if (pvmid)
+ vmid->un.cs_ctl_vmid = pvmid->un.cs_ctl_vmid;
+ else
+ vmid->un.cs_ctl_vmid = lpfc_vmid_get_cs_ctl(vport);
+ }
+}
+
/**
* lpfc_queuecommand - scsi_host_template queuecommand entry point
* @shost: kernel scsi host pointer.Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer