+#include <klibc/string.h>
+#include <lunaix/ds/btrie.h>
+#include <lunaix/fs.h>
+#include <lunaix/mm/page.h>
+#include <lunaix/mm/pmm.h>
+#include <lunaix/mm/valloc.h>
+#include <lunaix/mm/vmm.h>
+#include <lunaix/spike.h>
+
+#define PCACHE_DIRTY 0x1
+
+void
+pcache_init(struct pcache* pcache)
+{
+ btrie_init(&pcache->tree, PG_SIZE_BITS);
+ llist_init_head(&pcache->dirty);
+ llist_init_head(&pcache->pages);
+}
+
+void
+pcache_release_page(struct pcache* pcache, struct pcache_pg* page)
+{
+ pmm_free_page(KERNEL_PID, page->pg);
+ vmm_del_mapping(PD_REFERENCED, page->pg);
+
+ llist_delete(&page->pg_list);
+
+ vfree(page);
+
+ pcache->n_pages--;
+}
+
+struct pcache_pg*
+pcache_new_page(struct pcache* pcache, uint32_t index)
+{
+ void* pg = pmm_alloc_page(KERNEL_PID, 0);
+ void* pg_v = vmm_vmap(pg, PG_SIZE, PG_PREM_URW);
+ struct pcache_pg* ppg = valloc(sizeof(struct pcache_pg));
+ ppg->pg = pg_v;
+
+ llist_append(&pcache->pages, &ppg->pg_list);
+ btrie_set(&pcache->tree, index, ppg);
+
+ return ppg;
+}
+
+void
+pcache_set_dirty(struct pcache* pcache, struct pcache_pg* pg)
+{
+ if (!(pg->flags & PCACHE_DIRTY)) {
+ pg->flags |= PCACHE_DIRTY;
+ pcache->n_dirty++;
+ llist_append(&pcache->dirty, &pg->dirty_list);
+ }
+}
+
+struct pcache_pg*
+pcache_get_page(struct pcache* pcache,
+ uint32_t index,
+ uint32_t* offset,
+ struct pcache_pg** page)
+{
+ struct pcache_pg* pg = btrie_get(&pcache->tree, index);
+ int is_new = 0;
+ *offset = index & ((1 << pcache->tree.truncated) - 1);
+ if (!pg) {
+ pg = pcache_new_page(pcache, index);
+ pg->fpos = index - *offset;
+ pcache->n_pages++;
+ is_new = 1;
+ }
+ *page = pg;
+ return is_new;
+}
+
+int
+pcache_write(struct v_file* file, void* data, uint32_t len)
+{
+ uint32_t pg_off, buf_off = 0, fpos = file->f_pos;
+ struct pcache* pcache = file->inode->pg_cache;
+ struct pcache_pg* pg;
+
+ while (buf_off < len) {
+ pcache_get_page(pcache, fpos, &pg_off, &pg);
+ uint32_t wr_bytes = MIN(PG_SIZE - pg_off, len - buf_off);
+ memcpy(pg->pg + pg_off, (data + buf_off), wr_bytes);
+
+ pcache_set_dirty(pcache, pg);
+
+ buf_off += wr_bytes;
+ fpos += wr_bytes;
+ }
+
+ return buf_off;
+}
+
+int
+pcache_read(struct v_file* file, void* data, uint32_t len)
+{
+ uint32_t pg_off, buf_off = 0, new_pg = 0, fpos = file->f_pos;
+ int errno = 0;
+ struct pcache* pcache = file->inode->pg_cache;
+ struct pcache_pg* pg;
+
+ while (buf_off < len) {
+ if (pcache_get_page(pcache, fpos, &pg_off, &pg)) {
+ // Filling up the page
+ errno = file->ops.read(file, pg->pg, PG_SIZE, pg->fpos);
+ if (errno > 0 && errno < PG_SIZE) {
+ // EOF
+ len = buf_off + errno;
+ } else if (errno < 0) {
+ break;
+ }
+ }
+ uint32_t rd_bytes = MIN(PG_SIZE - pg_off, len - buf_off);
+ memcpy((data + buf_off), pg->pg + pg_off, rd_bytes);
+
+ buf_off += rd_bytes;
+ fpos += rd_bytes;
+ }
+
+ return errno < 0 ? errno : buf_off;
+}
+
+void
+pcache_release(struct pcache* pcache)
+{
+ struct pcache_pg *pos, *n;
+ llist_for_each(pos, n, &pcache->pages, pg_list)
+ {
+ vfree(pos);
+ }
+
+ btrie_release(&pcache->tree);
+}
+
+int
+pcache_commit(struct v_file* file, struct pcache_pg* page)
+{
+ if (!(page->flags & PCACHE_DIRTY)) {
+ return;
+ }
+
+ int errno = file->ops.write(file, page->pg, PG_SIZE, page->fpos);
+
+ if (!errno) {
+ page->flags &= ~PCACHE_DIRTY;
+ llist_delete(&page->dirty_list);
+ file->inode->pg_cache->n_dirty--;
+ }
+
+ return errno;
+}
+
+void
+pcache_commit_all(struct v_file* file)
+{
+ struct pcache* cache = file->inode->pg_cache;
+ struct pcache_pg *pos, *n;
+ llist_for_each(pos, n, &cache->dirty, dirty_list)
+ {
+ pcache_commit(file, pos);
+ }
+}
+
+void
+pcache_invalidate(struct v_file* file, struct pcache_pg* page)
+{
+ pcache_commit(file, page);
+ pcache_release_page(&file->inode->pg_cache, page);
+}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / commitdiff