Commit 53e80bd0 authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Michael Ellerman

powerpc/nvdimm: Add support for multibyte read/write for metadata

SCM_READ/WRITE_MEATADATA hcall supports multibyte read/write. This patch
updates the metadata read/write to use 1, 2, 4 or 8 byte read/write as
mentioned in PAPR document.

READ/WRITE_METADATA hcall supports the 1, 2, 4, or 8 bytes read/write.
For other values hcall results H_P3.

Hypervisor stores the metadata contents in big-endian format and in-order
to enable read/write in different granularity, we need to switch the contents
to big-endian before calling HCALL.

Based on an patch from Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
parent 2a0ffbd4
......@@ -100,39 +100,99 @@ static int papr_scm_meta_get(struct papr_scm_priv *p,
struct nd_cmd_get_config_data_hdr *hdr)
{
unsigned long data[PLPAR_HCALL_BUFSIZE];
unsigned long offset, data_offset;
int len, read;
int64_t ret;
if (hdr->in_offset >= p->metadata_size || hdr->in_length != 1)
if ((hdr->in_offset + hdr->in_length) >= p->metadata_size)
return -EINVAL;
for (len = hdr->in_length; len; len -= read) {
data_offset = hdr->in_length - len;
offset = hdr->in_offset + data_offset;
if (len >= 8)
read = 8;
else if (len >= 4)
read = 4;
else if (len >= 2)
read = 2;
else
read = 1;
ret = plpar_hcall(H_SCM_READ_METADATA, data, p->drc_index,
hdr->in_offset, 1);
offset, read);
if (ret == H_PARAMETER) /* bad DRC index */
return -ENODEV;
if (ret)
return -EINVAL; /* other invalid parameter */
hdr->out_buf[0] = data[0] & 0xff;
switch (read) {
case 8:
*(uint64_t *)(hdr->out_buf + data_offset) = be64_to_cpu(data[0]);
break;
case 4:
*(uint32_t *)(hdr->out_buf + data_offset) = be32_to_cpu(data[0] & 0xffffffff);
break;
case 2:
*(uint16_t *)(hdr->out_buf + data_offset) = be16_to_cpu(data[0] & 0xffff);
break;
case 1:
*(uint8_t *)(hdr->out_buf + data_offset) = (data[0] & 0xff);
break;
}
}
return 0;
}
static int papr_scm_meta_set(struct papr_scm_priv *p,
struct nd_cmd_set_config_hdr *hdr)
{
unsigned long offset, data_offset;
int len, wrote;
unsigned long data;
__be64 data_be;
int64_t ret;
if (hdr->in_offset >= p->metadata_size || hdr->in_length != 1)
if ((hdr->in_offset + hdr->in_length) >= p->metadata_size)
return -EINVAL;
ret = plpar_hcall_norets(H_SCM_WRITE_METADATA,
p->drc_index, hdr->in_offset, hdr->in_buf[0], 1);
for (len = hdr->in_length; len; len -= wrote) {
data_offset = hdr->in_length - len;
offset = hdr->in_offset + data_offset;
if (len >= 8) {
data = *(uint64_t *)(hdr->in_buf + data_offset);
data_be = cpu_to_be64(data);
wrote = 8;
} else if (len >= 4) {
data = *(uint32_t *)(hdr->in_buf + data_offset);
data &= 0xffffffff;
data_be = cpu_to_be32(data);
wrote = 4;
} else if (len >= 2) {
data = *(uint16_t *)(hdr->in_buf + data_offset);
data &= 0xffff;
data_be = cpu_to_be16(data);
wrote = 2;
} else {
data_be = *(uint8_t *)(hdr->in_buf + data_offset);
data_be &= 0xff;
wrote = 1;
}
ret = plpar_hcall_norets(H_SCM_WRITE_METADATA, p->drc_index,
offset, data_be, wrote);
if (ret == H_PARAMETER) /* bad DRC index */
return -ENODEV;
if (ret)
return -EINVAL; /* other invalid parameter */
}
return 0;
}
......@@ -154,7 +214,7 @@ int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
get_size_hdr = buf;
get_size_hdr->status = 0;
get_size_hdr->max_xfer = 1;
get_size_hdr->max_xfer = 8;
get_size_hdr->config_size = p->metadata_size;
*cmd_rc = 0;
break;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment