On 05/17/2018 05:26 PM, Michael Bringmann wrote:
> powerpc migration/drmem: Export many of the functions of DRMEM to
> parse "ibm,dynamic-memory" and "ibm,dynamic-memory-v2" during
> hotplug operations and for Post Migration events.
>
> Also modify the DRMEM initialization code to allow it to,
>
> * Be called after system initialization
> * Provide a separate user copy of the LMB array that is produces
> * Free the user copy upon request
>
> Signed-off-by: Michael Bringmann <m...@linux.vnet.ibm.com>
> ---
> Changes in RFC:
> -- Separate DRMEM changes into a standalone patch
> -- Do not export excess functions. Make exported names more explicit.
> -- Add new iterator to work through a pair of drmem_info arrays.
> -- Modify DRMEM code to replace usages of dt_root_addr_cells, and
> dt_mem_next_cell, as these are only available at first boot.
> -- Rebase to 4.17-rc5 kernel
> ---
> arch/powerpc/include/asm/drmem.h | 10 +++++
> arch/powerpc/mm/drmem.c | 78
> +++++++++++++++++++++++++++-----------
> 2 files changed, 66 insertions(+), 22 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/drmem.h
> b/arch/powerpc/include/asm/drmem.h
> index ce242b9..c964b89 100644
> --- a/arch/powerpc/include/asm/drmem.h
> +++ b/arch/powerpc/include/asm/drmem.h
> @@ -35,6 +35,13 @@ struct drmem_lmb_info {
> &drmem_info->lmbs[0], \
> &drmem_info->lmbs[drmem_info->n_lmbs - 1])
>
> +#define for_each_pair_drmem_lmb(dinfo1, lmb1, dinfo2, lmb2) \
> + for ((lmb1) = (&dinfo1->lmbs[0]), \
> + (lmb2) = (&dinfo2->lmbs[0]); \
> + ((lmb1) <= (&dinfo1->lmbs[dinfo1->n_lmbs - 1])) && \
> + ((lmb2) <= (&dinfo2->lmbs[dinfo2->n_lmbs - 1])); \
> + (lmb1)++, (lmb2)++)
> +
> /*
> * The of_drconf_cell_v1 struct defines the layout of the LMB data
> * specified in the ibm,dynamic-memory device tree property.
> @@ -94,6 +101,9 @@ void __init walk_drmem_lmbs(struct device_node *dn,
> void (*func)(struct drmem_lmb *, const __be32 **));
> int drmem_update_dt(void);
>
> +struct drmem_lmb_info* drmem_init_lmbs(struct property *prop);
> +void drmem_lmbs_free(struct drmem_lmb_info *dinfo);
> +
> #ifdef CONFIG_PPC_PSERIES
> void __init walk_drmem_lmbs_early(unsigned long node,
> void (*func)(struct drmem_lmb *, const __be32 **));
> diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c
> index 3f18036..d9b281c 100644
> --- a/arch/powerpc/mm/drmem.c
> +++ b/arch/powerpc/mm/drmem.c
> @@ -20,6 +20,7 @@
>
> static struct drmem_lmb_info __drmem_info;
> struct drmem_lmb_info *drmem_info = &__drmem_info;
> +static int n_root_addr_cells;
>
> u64 drmem_lmb_memory_max(void)
> {
> @@ -193,12 +194,13 @@ int drmem_update_dt(void)
> return rc;
> }
>
> -static void __init read_drconf_v1_cell(struct drmem_lmb *lmb,
> +static void read_drconf_v1_cell(struct drmem_lmb *lmb,
> const __be32 **prop)
> {
> const __be32 *p = *prop;
>
> - lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
> + lmb->base_addr = of_read_number(p, n_root_addr_cells);
> + p += n_root_addr_cells;
> lmb->drc_index = of_read_number(p++, 1);
>
> p++; /* skip reserved field */
> @@ -209,7 +211,7 @@ static void __init read_drconf_v1_cell(struct drmem_lmb
> *lmb,
> *prop = p;
> }
>
> -static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32
> *usm,
> +static void __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *data,
> void (*func)(struct drmem_lmb *, const __be32 **))
> {
> struct drmem_lmb lmb;
> @@ -221,17 +223,18 @@ static void __init __walk_drmem_v1_lmbs(const __be32
> *prop, const __be32 *usm,
>
> for (i = 0; i < n_lmbs; i++) {
> read_drconf_v1_cell(&lmb, &prop);
> - func(&lmb, &usm);
> + func(&lmb, &data);
Is there a need to change the variable name from usm to data (bot here and
below)?
> }
> }
>
> -static void __init read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
> +static void read_drconf_v2_cell(struct of_drconf_cell_v2 *dr_cell,
> const __be32 **prop)
> {
> const __be32 *p = *prop;
>
> dr_cell->seq_lmbs = of_read_number(p++, 1);
> - dr_cell->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p);
> + dr_cell->base_addr = of_read_number(p, n_root_addr_cells);
> + p += n_root_addr_cells;
> dr_cell->drc_index = of_read_number(p++, 1);
> dr_cell->aa_index = of_read_number(p++, 1);
> dr_cell->flags = of_read_number(p++, 1);
> @@ -239,7 +242,7 @@ static void __init read_drconf_v2_cell(struct
> of_drconf_cell_v2 *dr_cell,
> *prop = p;
> }
>
> -static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32
> *usm,
> +static void __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *data,
> void (*func)(struct drmem_lmb *, const __be32 **))
> {
> struct of_drconf_cell_v2 dr_cell;
> @@ -263,7 +266,7 @@ static void __init __walk_drmem_v2_lmbs(const __be32
> *prop, const __be32 *usm,
> lmb.aa_index = dr_cell.aa_index;
> lmb.flags = dr_cell.flags;
>
> - func(&lmb, &usm);
> + func(&lmb, &data);
> }
> }
> }
> @@ -275,6 +278,9 @@ void __init walk_drmem_lmbs_early(unsigned long node,
> const __be32 *prop, *usm;
> int len;
>
> + if (n_root_addr_cells == 0)
> + n_root_addr_cells = dt_root_addr_cells;
> +
> prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
> if (!prop || len < dt_root_size_cells * sizeof(__be32))
> return;
> @@ -353,24 +359,26 @@ void __init walk_drmem_lmbs(struct device_node *dn,
> }
> }
>
> -static void __init init_drmem_v1_lmbs(const __be32 *prop)
> +static void init_drmem_v1_lmbs(const __be32 *prop,
> + struct drmem_lmb_info *dinfo)
Please make sure you line up the function args, here and other places below.
> {
> struct drmem_lmb *lmb;
>
> - drmem_info->n_lmbs = of_read_number(prop++, 1);
> - if (drmem_info->n_lmbs == 0)
> + dinfo->n_lmbs = of_read_number(prop++, 1);
> + if (dinfo->n_lmbs == 0)
> return;
>
> - drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
> + dinfo->lmbs = kcalloc(dinfo->n_lmbs, sizeof(*lmb),
> GFP_KERNEL);> - if (!drmem_info->lmbs)
> + if (!dinfo->lmbs)
> return;
>
> for_each_drmem_lmb(lmb)
> read_drconf_v1_cell(lmb, &prop);
> }
>
> -static void __init init_drmem_v2_lmbs(const __be32 *prop)
> +static void init_drmem_v2_lmbs(const __be32 *prop,
> + struct drmem_lmb_info *dinfo)
> {
> struct drmem_lmb *lmb;
> struct of_drconf_cell_v2 dr_cell;
> @@ -386,12 +394,12 @@ static void __init init_drmem_v2_lmbs(const __be32
> *prop)
> p = prop;
> for (i = 0; i < lmb_sets; i++) {
> read_drconf_v2_cell(&dr_cell, &p);
> - drmem_info->n_lmbs += dr_cell.seq_lmbs;
> + dinfo->n_lmbs += dr_cell.seq_lmbs;
> }
>
> - drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb),
> + dinfo->lmbs = kcalloc(dinfo->n_lmbs, sizeof(*lmb),
> GFP_KERNEL);
> - if (!drmem_info->lmbs)
> + if (!dinfo->lmbs)
> return;
>
> /* second pass, read in the LMB information */
> @@ -402,25 +410,51 @@ static void __init init_drmem_v2_lmbs(const __be32
> *prop)
> read_drconf_v2_cell(&dr_cell, &p);
>
> for (j = 0; j < dr_cell.seq_lmbs; j++) {
> - lmb = &drmem_info->lmbs[lmb_index++];
> + lmb = &dinfo->lmbs[lmb_index++];
>
> lmb->base_addr = dr_cell.base_addr;
> - dr_cell.base_addr += drmem_info->lmb_size;
> + dr_cell.base_addr += dinfo->lmb_size;
>
> lmb->drc_index = dr_cell.drc_index;
> dr_cell.drc_index++;
>
> lmb->aa_index = dr_cell.aa_index;
> - lmb->flags = dr_cell.flags;
Why are you removing the setting of the flags field?
> }
> }
> }
>
> +void drmem_lmbs_free(struct drmem_lmb_info *dinfo)
> +{
> + if (dinfo) {
> + kfree(dinfo->lmbs);
> + kfree(dinfo);
> + }
> +}
> +
> +struct drmem_lmb_info* drmem_init_lmbs(struct property *prop)
Small nit, but this should probably be named drmem_lmbs_init. This follows
more closely to the naming used elsewhere.
-Nathan
> +{
> + struct drmem_lmb_info *dinfo;
> +
> + dinfo = kzalloc(sizeof(*dinfo), GFP_KERNEL);
> + if (!dinfo)
> + return NULL;
> +
> + if (!strcmp("ibm,dynamic-memory", prop->name))
> + init_drmem_v1_lmbs(prop->value, dinfo);
> + else if (!strcmp("ibm,dynamic-memory-v2", prop->name))
> + init_drmem_v2_lmbs(prop->value, dinfo);
> +
> + return dinfo;
> +}
> +
> static int __init drmem_init(void)
> {
> struct device_node *dn;
> const __be32 *prop;
>
> + if (n_root_addr_cells == 0)
> + n_root_addr_cells = dt_root_addr_cells;
> +
> dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
> if (!dn) {
> pr_info("No dynamic reconfiguration memory found\n");
> @@ -434,11 +468,11 @@ static int __init drmem_init(void)
>
> prop = of_get_property(dn, "ibm,dynamic-memory", NULL);
> if (prop) {
> - init_drmem_v1_lmbs(prop);
> + init_drmem_v1_lmbs(prop, drmem_info);
> } else {
> prop = of_get_property(dn, "ibm,dynamic-memory-v2", NULL);
> if (prop)
> - init_drmem_v2_lmbs(prop);
> + init_drmem_v2_lmbs(prop, drmem_info);
> }
>
> of_node_put(dn);
>
