diff options
| -rw-r--r-- | kernel/features/fs.c | 47 |
1 files changed, 27 insertions, 20 deletions
diff --git a/kernel/features/fs.c b/kernel/features/fs.c index 56d253a..920add1 100644 --- a/kernel/features/fs.c +++ b/kernel/features/fs.c @@ -136,9 +136,6 @@ s32 vfs_read(const char *path, void *buf, u32 offset, u32 count) if (!buf || !memory_valid(buf)) return -EFAULT; - if (offset > count) - return -EINVAL; - struct mount_info *m = vfs_find_mount_info(path); if (!m || !m->dev || !m->dev->vfs) return -ENOENT; @@ -168,9 +165,6 @@ s32 vfs_write(const char *path, void *buf, u32 offset, u32 count) if (!buf || !memory_valid(buf)) return -EFAULT; - if (offset > count) - return -EINVAL; - struct mount_info *m = vfs_find_mount_info(path); if (!m || !m->dev || !m->dev->vfs) return -ENOENT; @@ -485,25 +479,31 @@ static u32 read_indirect(u32 indirect, u32 block_num, struct device *dev) static s32 read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 count, struct device *dev) { - // TODO: Support read offset - UNUSED(offset); - if (!in || !buf) return -EINVAL; - u32 num_blocks = in->blocks / (BLOCK_SIZE / SECTOR_SIZE); + if (in->size == 0) + return 0; + + u32 num_blocks = in->blocks / (BLOCK_SIZE / SECTOR_SIZE) + 1; if (!num_blocks) return -EINVAL; - // TODO: memcpy block chunks until count is copied - while (BLOCK_SIZE * num_blocks > count) - num_blocks--; + u32 first_block = offset / BLOCK_SIZE; + u32 last_block = (offset + count) / BLOCK_SIZE; + if (last_block >= num_blocks) + last_block = num_blocks - 1; + u32 first_block_offset = offset % BLOCK_SIZE; + + u32 remaining = MIN(count, in->size - offset); + u32 copied = 0; u32 indirect = 0; u32 blocknum = 0; + // TODO: Support triply indirect pointers - for (u32 i = 0; i < num_blocks; i++) { + for (u32 i = first_block; i <= last_block; i++) { if (i < 12) { blocknum = in->block[i]; } else if (i < BLOCK_COUNT + 12) { @@ -518,9 +518,16 @@ static s32 read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 count, s } char *data = buffer_read(blocknum, dev); - memcpy((u32 *)((u32)buf + i * BLOCK_SIZE), data, BLOCK_SIZE); + u32 block_offset = (i == first_block) ? first_block_offset : 0; + u32 byte_count = MIN(BLOCK_SIZE - block_offset, remaining); + + memcpy((u8 *)buf + copied, data + block_offset, byte_count); + + copied += byte_count; + remaining -= byte_count; + free(data); - /* printf("Loaded %d of %d\n", i + 1, num_blocks); */ + /* printf("Loaded %d of %d\n", i + 1, last_block); */ } if (indirect_cache) { @@ -534,7 +541,7 @@ static s32 read_inode(struct ext2_inode *in, void *buf, u32 offset, u32 count, s indirect_cache = NULL; } - return count; + return copied; } static u32 find_inode(const char *name, u32 dir_inode, struct device *dev) @@ -627,11 +634,11 @@ s32 ext2_stat(const char *path, struct stat *buf, struct device *dev) if (find_inode_by_path(path, &in, dev) != &in) return -ENOENT; - u32 num_blocks = in.blocks / (BLOCK_SIZE / SECTOR_SIZE); - u32 sz = BLOCK_SIZE * num_blocks; + //u32 num_blocks = in.blocks / (BLOCK_SIZE / SECTOR_SIZE); + //u32 sz = BLOCK_SIZE * num_blocks; buf->dev_id = dev->id; - buf->size = sz; // Actually in->size but ext2.. + buf->size = in.size; return 0; } |