sfc: Eliminate struct efx_mtd

Currently we use struct efx_mtd to represent a physical NVRAM device
and struct efx_mtd_partition to represent a partition on that device.
But this only really makes sense for Falcon, as we don't know or care
whether MC-managed NVRAM partitions are on one or more physical
devices.  It complicates iteration and provides little benefit.
Therefore:

- Replace the pointer to efx_mtd in mtd_info::priv with a pointer to efx_nic
- Move the falcon_spi_device pointer into the union in struct efx_mtd_partition
- Move the device name to efx_mtd_partition::dev_type_name
- Move the efx_mtd_ops pointer to efx_nic::mtd_ops
- Make efx_nic::mtd_list a list of partitions

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

2 files changed, 120 insertions, 160 deletions

diff --git a/drivers/net/ethernet/sfc/mtd.c b/drivers/net/ethernet/sfc/mtd.c
index e4b35c61e90b..ba6c87a73d86 100644
--- a/drivers/net/ethernet/sfc/mtd.c
+++ b/drivers/net/ethernet/sfc/mtd.c
@@ -25,6 +25,7 @@
 #define FALCON_SPI_VERIFY_BUF_LEN 16
 
 struct efx_mtd_partition {
+        struct list_head node;
         struct mtd_info mtd;
         union {
                 struct {
@@ -32,8 +33,12 @@ struct efx_mtd_partition {
                         u8 nvram_type;
                         u16 fw_subtype;
                 } mcdi;
-                size_t offset;
+                struct {
+                        const struct falcon_spi_device *spi;
+                        size_t offset;
+                } falcon;
         };
+        const char *dev_type_name;
         const char *type_name;
         char name[IFNAMSIZ + 20];
 };
@@ -47,21 +52,6 @@ struct efx_mtd_ops {
         int (*sync)(struct mtd_info *mtd);
 };
 
-struct efx_mtd {
-        struct list_head node;
-        struct efx_nic *efx;
-        const struct falcon_spi_device *spi;
-        const char *name;
-        const struct efx_mtd_ops *ops;
-        size_t n_parts;
-        struct efx_mtd_partition part[0];
-};
-
-#define efx_for_each_partition(part, efx_mtd)                   \
-        for ((part) = &(efx_mtd)->part[0];                      \
-             (part) != &(efx_mtd)->part[(efx_mtd)->n_parts];    \
-             (part)++)
-
 #define to_efx_mtd_partition(mtd)                               \
         container_of(mtd, struct efx_mtd_partition, mtd)
 
@@ -73,9 +63,8 @@ static int siena_mtd_probe(struct efx_nic *efx);
 static int
 falcon_spi_slow_wait(struct efx_mtd_partition *part, bool uninterruptible)
 {
-        struct efx_mtd *efx_mtd = part->mtd.priv;
-        const struct falcon_spi_device *spi = efx_mtd->spi;
-        struct efx_nic *efx = efx_mtd->efx;
+        const struct falcon_spi_device *spi = part->falcon.spi;
+        struct efx_nic *efx = part->mtd.priv;
         u8 status;
         int rc, i;
 
@@ -93,7 +82,8 @@ falcon_spi_slow_wait(struct efx_mtd_partition *part, bool uninterruptible)
                 if (signal_pending(current))
                         return -EINTR;
         }
-        pr_err("%s: timed out waiting for %s\n", part->name, efx_mtd->name);
+        pr_err("%s: timed out waiting for %s\n",
+               part->name, part->dev_type_name);
         return -ETIMEDOUT;
 }
 
@@ -135,9 +125,8 @@ falcon_spi_unlock(struct efx_nic *efx, const struct falcon_spi_device *spi)
 static int
 falcon_spi_erase(struct efx_mtd_partition *part, loff_t start, size_t len)
 {
-        struct efx_mtd *efx_mtd = part->mtd.priv;
-        const struct falcon_spi_device *spi = efx_mtd->spi;
-        struct efx_nic *efx = efx_mtd->efx;
+        const struct falcon_spi_device *spi = part->falcon.spi;
+        struct efx_nic *efx = part->mtd.priv;
         unsigned pos, block_len;
         u8 empty[FALCON_SPI_VERIFY_BUF_LEN];
         u8 buffer[FALCON_SPI_VERIFY_BUF_LEN];
@@ -185,10 +174,10 @@ falcon_spi_erase(struct efx_mtd_partition *part, loff_t start, size_t len)
 
 static int efx_mtd_erase(struct mtd_info *mtd, struct erase_info *erase)
 {
-        struct efx_mtd *efx_mtd = mtd->priv;
+        struct efx_nic *efx = mtd->priv;
         int rc;
 
-        rc = efx_mtd->ops->erase(mtd, erase->addr, erase->len);
+        rc = efx->mtd_ops->erase(mtd, erase->addr, erase->len);
         if (rc == 0) {
                 erase->state = MTD_ERASE_DONE;
         } else {
@@ -202,13 +191,13 @@ static int efx_mtd_erase(struct mtd_info *mtd, struct erase_info *erase)
 static void efx_mtd_sync(struct mtd_info *mtd)
 {
         struct efx_mtd_partition *part = to_efx_mtd_partition(mtd);
-        struct efx_mtd *efx_mtd = mtd->priv;
+        struct efx_nic *efx = mtd->priv;
         int rc;
 
-        rc = efx_mtd->ops->sync(mtd);
+        rc = efx->mtd_ops->sync(mtd);
         if (rc)
                 pr_err("%s: %s sync failed (%d)\n",
-                       part->name, efx_mtd->name, rc);
+                       part->name, part->dev_type_name, rc);
 }
 
 static void efx_mtd_remove_partition(struct efx_mtd_partition *part)
@@ -222,86 +211,84 @@ static void efx_mtd_remove_partition(struct efx_mtd_partition *part)
                 ssleep(1);
         }
         WARN_ON(rc);
+        list_del(&part->node);
 }
 
-static void efx_mtd_remove_device(struct efx_mtd *efx_mtd)
-{
-        struct efx_mtd_partition *part;
-
-        efx_for_each_partition(part, efx_mtd)
-                efx_mtd_remove_partition(part);
-        list_del(&efx_mtd->node);
-        kfree(efx_mtd);
-}
-
-static void efx_mtd_rename_device(struct efx_mtd *efx_mtd)
+static void efx_mtd_rename_partition(struct efx_mtd_partition *part)
 {
-        struct efx_mtd_partition *part;
+        struct efx_nic *efx = part->mtd.priv;
 
-        efx_for_each_partition(part, efx_mtd)
-                if (efx_nic_rev(efx_mtd->efx) >= EFX_REV_SIENA_A0)
-                        snprintf(part->name, sizeof(part->name),
-                                 "%s %s:%02x", efx_mtd->efx->name,
-                                 part->type_name, part->mcdi.fw_subtype);
-                else
-                        snprintf(part->name, sizeof(part->name),
-                                 "%s %s", efx_mtd->efx->name,
-                                 part->type_name);
+        if (efx_nic_rev(efx) >= EFX_REV_SIENA_A0)
+                snprintf(part->name, sizeof(part->name), "%s %s:%02x",
+                         efx->name, part->type_name, part->mcdi.fw_subtype);
+        else
+                snprintf(part->name, sizeof(part->name), "%s %s",
+                         efx->name, part->type_name);
 }
 
-static int efx_mtd_probe_device(struct efx_nic *efx, struct efx_mtd *efx_mtd)
+static int efx_mtd_add(struct efx_nic *efx,
+                       struct efx_mtd_partition *parts, size_t n_parts)
 {
         struct efx_mtd_partition *part;
+        size_t i;
 
-        efx_mtd->efx = efx;
+        for (i = 0; i < n_parts; i++) {
+                part = &parts[i];
 
-        efx_mtd_rename_device(efx_mtd);
-
-        efx_for_each_partition(part, efx_mtd) {
                 part->mtd.writesize = 1;