+#include <lunaix/mm/valloc.h>
+#include <lunaix/mm/page.h>
+#include "ext2.h"
+
+#define blkpos(e_sb, fpos) ((fpos) / (e_sb)->block_size)
+#define blkoff(e_sb, fpos) ((fpos) % (e_sb)->block_size)
+
+int
+ext2_open_inode(struct v_inode* inode, struct v_file* file)
+{
+ int errno = 0;
+ struct ext2_file* e_file;
+
+ e_file = valloc(sizeof(*e_file));
+ e_file->b_ino = EXT2_INO(inode);
+
+ file->data = e_file;
+
+ if (check_directory_node(inode)) {
+ errno = ext2dr_open(inode, file);
+ goto done;
+ }
+
+ // XXX anything for regular file?
+
+done:
+ if (!errno) {
+ return 0;
+ }
+
+ vfree(e_file);
+ file->data = NULL;
+ return errno;
+}
+
+int
+ext2_close_inode(struct v_file* file)
+{
+ ext2ino_update(file->inode);
+
+ if (check_directory_node(file->inode)) {
+ ext2dr_close(file->inode, file);
+ }
+
+ vfree(file->data);
+ file->data = NULL;
+ return 0;
+}
+
+int
+ext2_sync_inode(struct v_inode* inode)
+{
+ // TODO
+ // a modification to an inode may involves multiple
+ // blkbuf scattering among different groups.
+ // For now, we just sync everything, until we figure out
+ // a way to track each dirtied blkbuf w.r.t inode
+ ext2ino_resizing(inode, inode->fsize);
+ blkbuf_syncall(inode->sb->blks, false);
+
+ return 0;
+}
+
+int
+ext2_file_sync(struct v_file* file)
+{
+ return ext2_sync_inode(file->inode);
+}
+
+int
+ext2_seek_inode(struct v_file* file, size_t offset)
+{
+ if (check_directory_node(file->inode)) {
+ return ext2dr_seek(file, offset);
+ }
+
+ // nothing to do, seek on file pos handled by vfs
+ return 0;
+}
+
+int
+ext2_inode_read(struct v_inode *inode,
+ void *buffer, size_t len, size_t fpos)
+{
+ struct ext2_sbinfo* e_sb;
+ struct ext2_iterator iter;
+ struct ext2b_inode* b_ino;
+ struct ext2_inode* e_ino;
+ unsigned int off;
+ unsigned int end;
+ unsigned int sz = 0, blksz, movsz;
+
+ e_sb = EXT2_SB(inode->sb);
+ e_ino = EXT2_INO(inode);
+ b_ino = e_ino->ino;
+ blksz = e_sb->block_size;
+ end = fpos + len;
+
+ ext2db_itbegin(&iter, inode);
+ ext2db_itffw(&iter, fpos / blksz);
+
+ while (fpos < end && ext2db_itnext(&iter)) {
+ off = fpos % blksz;
+ movsz = MIN(end - fpos, blksz - off);
+
+ memcpy(buffer, offset(iter.data, off), movsz);
+
+ buffer = offset(buffer, movsz);
+ fpos += movsz;
+ sz += movsz;
+ }
+
+ ext2db_itend(&iter);
+ return itstate_sel(&iter, MIN(sz, e_ino->isize));
+}
+
+int
+ext2_inode_read_page(struct v_inode *inode, void *buffer, size_t fpos)
+{
+ struct ext2_sbinfo* e_sb;
+ struct ext2_iterator iter;
+ struct ext2_inode* e_ino;
+ struct ext2b_inode* b_ino;
+ unsigned int blk_start, n,
+ transfer_sz, total_sz = 0;
+
+ assert(!va_offset(fpos));
+
+ e_sb = EXT2_SB(inode->sb);
+ e_ino = EXT2_INO(inode);
+ b_ino = e_ino->ino;
+
+ blk_start = fpos / e_sb->block_size;
+ n = PAGE_SIZE / e_sb->block_size;
+ transfer_sz = MIN(PAGE_SIZE, e_sb->block_size);
+
+ ext2db_itbegin(&iter, inode);
+ ext2db_itffw(&iter, blk_start);
+
+ while (n-- && ext2db_itnext(&iter))
+ {
+ memcpy(buffer, iter.data, transfer_sz);
+ buffer = offset(buffer, transfer_sz);
+ total_sz += transfer_sz;
+ }
+
+ ext2db_itend(&iter);
+ return itstate_sel(&iter, MIN(total_sz, e_ino->isize));
+}
+
+int
+ext2_inode_write(struct v_inode *inode,
+ void *buffer, size_t len, size_t fpos)
+{
+ int errno;
+ unsigned int acc, blk_off, end, size;
+ struct ext2_sbinfo* e_sb;
+ bbuf_t buf;
+
+ e_sb = EXT2_SB(inode->sb);
+
+ acc = 0;
+ end = fpos + len;
+ while (fpos < end) {
+ errno = ext2db_acquire(inode, blkpos(e_sb, fpos), &buf);
+ if (errno) {
+ return errno;
+ }
+
+ blk_off = blkoff(e_sb, fpos);
+ size = e_sb->block_size - blk_off;
+
+ memcpy(offset(blkbuf_data(buf), blk_off), buffer, size);
+ buffer = offset(buffer, size);
+
+ fsblock_dirty(buf);
+ fsblock_put(buf);
+
+ fpos += size;
+ acc += size;
+ }
+
+ return (int)acc;
+}
+
+int
+ext2_inode_write_page(struct v_inode *inode, void *buffer, size_t fpos)
+{
+ return ext2_inode_write(inode, buffer, PAGE_SIZE, fpos);
+}
+
+#define SYMLNK_INPLACE \
+ sizeof(((struct ext2b_inode*)0)->i_block_arr)
+
+static inline int
+__readlink_symlink(struct v_inode *this, char* path)
+{
+ size_t size;
+ char* link = NULL;
+ int errno;
+ bbuf_t buf;
+ struct ext2_inode* e_ino;
+
+ e_ino = EXT2_INO(this);
+ size = e_ino->isize;
+ if (size <= SYMLNK_INPLACE) {
+ link = (char*) e_ino->ino->i_block_arr;
+ strncpy(path, link, size);
+ }
+ else {
+ buf = ext2db_get(this, 0);
+ if (blkbuf_errbuf(buf)) {
+ return EIO;
+ }
+
+ link = blkbuf_data(buf);
+ strncpy(path, link, size);
+
+ fsblock_put(buf);
+ }
+
+ return 0;
+}
+
+int
+ext2_get_symlink(struct v_inode *this, const char **path_out)
+{
+ int errno;
+ size_t size;
+ char* symlink;
+ struct ext2_inode* e_ino;
+
+ e_ino = EXT2_INO(this);
+ size = e_ino->isize;
+
+ if (!size) {
+ return ENOENT;
+ }
+
+ if (!e_ino->symlink) {
+ symlink = valloc(size);
+ if ((errno = __readlink_symlink(this, symlink))) {
+ vfree(symlink);
+ return errno;
+ }
+
+ e_ino->symlink = symlink;
+ }
+
+ *path_out = e_ino->symlink;
+
+ return size;
+}
+
+int
+ext2_set_symlink(struct v_inode *this, const char *target)
+{
+ int errno = 0;
+ bbuf_t buf = NULL;
+ char* link;
+ size_t size, new_len;
+ struct ext2_inode* e_ino;
+
+ e_ino = EXT2_INO(this);
+ size = e_ino->isize;
+ new_len = strlen(target);
+
+ if (new_len > this->sb->blksize) {
+ return ENAMETOOLONG;
+ }
+
+ if (size != new_len) {
+ vfree_safe(e_ino->symlink);
+ e_ino->symlink = valloc(new_len);
+ }
+
+ link = (char*) e_ino->ino->i_block_arr;
+
+ // if new size is shrinked to inplace range
+ if (size > SYMLNK_INPLACE && new_len <= SYMLNK_INPLACE)
+ {
+ ext2db_free_pos(this, 0);
+ }
+
+ // if new size is too big to fit inpalce
+ if (new_len > SYMLNK_INPLACE) {
+
+ // repurpose the i_block array back to normal
+ if (size <= SYMLNK_INPLACE) {
+ memset(link, 0, SYMLNK_INPLACE);
+ }
+
+ errno = ext2db_acquire(this, 0, &buf);
+ if (errno) {
+ goto done;
+ }
+
+ link = blkbuf_data(buf);
+ }
+
+ strncpy(e_ino->symlink, target, new_len);
+ strncpy(link, target, new_len);
+
+ ext2ino_update(this);
+ ext2ino_resizing(this, new_len);
+
+ if (buf) {
+ fsblock_put(buf);
+ }
+
+done:
+ return errno;
+}
\ No newline at end of file
git://scm.lunaixsky.com / lunaix-os.git / blobdiff