static __inline void
init_sg_elem(struct scatterlist *sgp, struct page *p, int offset, void *addr, size_t length)
{
sgp->length = length;
if (p) {
sg_assign_page(sgp, p);
sgp->offset = offset;
} else {
sg_assign_page(sgp, virt_to_page(addr));
sgp->offset = offset_in_page(addr);
}
}
/* rd_build_device_space():
*
*
*/
static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
u32 total_sg_needed, unsigned char init_payload)
{
u32 i = 0, j, page_offset = 0, sg_per_table;
u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
sizeof(struct scatterlist));
struct page *pg;
struct scatterlist *sg;
unsigned char *p;
while (total_sg_needed) {
sg_per_table = (total_sg_needed > max_sg_per_table) ?
max_sg_per_table : total_sg_needed;
sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
GFP_KERNEL);
if (!sg) {
pr_err("Unable to allocate scatterlist array"
" for struct rd_dev\n");
return -ENOMEM;
}
sg_init_table(sg, sg_per_table);
sg_table[i].sg_table = sg;
sg_table[i].rd_sg_count = sg_per_table;
sg_table[i].page_start_offset = page_offset;
sg_table[i++].page_end_offset = (page_offset + sg_per_table)
- 1;
for (j = 0; j < sg_per_table; j++) {
pg = alloc_pages(GFP_KERNEL | __GFP_ZERO, 0);
if (!pg) {
pr_err("Unable to allocate scatterlist"
" pages for struct rd_dev_sg_table\n");
return -ENOMEM;
}
sg_assign_page(&sg[j], pg);
sg[j].length = PAGE_SIZE;
p = kmap(pg);
memset(p, init_payload, PAGE_SIZE);
kunmap(pg);
}
page_offset += sg_per_table;
total_sg_needed -= sg_per_table;
}
return 0;
}
/* rd_build_device_space():
*
*
*/
static int rd_build_device_space(struct rd_dev *rd_dev)
{
u32 i = 0, j, page_offset = 0, sg_per_table, sg_tables, total_sg_needed;
u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
sizeof(struct scatterlist));
struct rd_dev_sg_table *sg_table;
struct page *pg;
struct scatterlist *sg;
if (rd_dev->rd_page_count <= 0) {
pr_err("Illegal page count: %u for Ramdisk device\n",
rd_dev->rd_page_count);
return -EINVAL;
}
total_sg_needed = rd_dev->rd_page_count;
sg_tables = (total_sg_needed / max_sg_per_table) + 1;
sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL);
if (!sg_table) {
pr_err("Unable to allocate memory for Ramdisk"
" scatterlist tables\n");
return -ENOMEM;
}
rd_dev->sg_table_array = sg_table;
rd_dev->sg_table_count = sg_tables;
while (total_sg_needed) {
sg_per_table = (total_sg_needed > max_sg_per_table) ?
max_sg_per_table : total_sg_needed;
sg = kzalloc(sg_per_table * sizeof(struct scatterlist),
GFP_KERNEL);
if (!sg) {
pr_err("Unable to allocate scatterlist array"
" for struct rd_dev\n");
return -ENOMEM;
}
sg_init_table(sg, sg_per_table);
sg_table[i].sg_table = sg;
sg_table[i].rd_sg_count = sg_per_table;
sg_table[i].page_start_offset = page_offset;
sg_table[i++].page_end_offset = (page_offset + sg_per_table)
- 1;
for (j = 0; j < sg_per_table; j++) {
pg = alloc_pages(GFP_KERNEL, 0);
if (!pg) {
pr_err("Unable to allocate scatterlist"
" pages for struct rd_dev_sg_table\n");
return -ENOMEM;
}
sg_assign_page(&sg[j], pg);
sg[j].length = PAGE_SIZE;
}
page_offset += sg_per_table;
total_sg_needed -= sg_per_table;
}
pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u space of"
" %u pages in %u tables\n", rd_dev->rd_host->rd_host_id,
rd_dev->rd_dev_id, rd_dev->rd_page_count,
rd_dev->sg_table_count);
return 0;
}
/* rd_build_device_space():
*
*
*/
static int rd_allocate_sgl_table(struct rd_dev *rd_dev, struct rd_dev_sg_table *sg_table,
u32 total_sg_needed, unsigned char init_payload)
{
u32 i = 0, j, page_offset = 0, sg_per_table;
u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE /
sizeof(struct scatterlist));
struct page *pg;
struct scatterlist *sg;
unsigned char *p;
while (total_sg_needed) {
unsigned int chain_entry = 0;
sg_per_table = (total_sg_needed > max_sg_per_table) ?
max_sg_per_table : total_sg_needed;
#ifdef CONFIG_ARCH_HAS_SG_CHAIN
/*
* Reserve extra element for chain entry
*/
if (sg_per_table < total_sg_needed)
chain_entry = 1;
#endif /* CONFIG_ARCH_HAS_SG_CHAIN */
sg = kcalloc(sg_per_table + chain_entry, sizeof(*sg),
GFP_KERNEL);
if (!sg) {
pr_err("Unable to allocate scatterlist array"
" for struct rd_dev\n");
return -ENOMEM;
}
sg_init_table(sg, sg_per_table + chain_entry);
#ifdef CONFIG_ARCH_HAS_SG_CHAIN
if (i > 0) {
sg_chain(sg_table[i - 1].sg_table,
max_sg_per_table + 1, sg);
}
#endif /* CONFIG_ARCH_HAS_SG_CHAIN */
sg_table[i].sg_table = sg;
sg_table[i].rd_sg_count = sg_per_table;
sg_table[i].page_start_offset = page_offset;
sg_table[i++].page_end_offset = (page_offset + sg_per_table)
- 1;
for (j = 0; j < sg_per_table; j++) {
pg = alloc_pages(GFP_KERNEL, 0);
if (!pg) {
pr_err("Unable to allocate scatterlist"
" pages for struct rd_dev_sg_table\n");
return -ENOMEM;
}
sg_assign_page(&sg[j], pg);
sg[j].length = PAGE_SIZE;
p = kmap(pg);
memset(p, init_payload, PAGE_SIZE);
kunmap(pg);
}
page_offset += sg_per_table;
total_sg_needed -= sg_per_table;
}
return 0;
}
