block/partitions/ultrix.c

Source file repositories/reference/linux-study-clean/block/partitions/ultrix.c

File Facts

System
Linux kernel
Corpus path
block/partitions/ultrix.c
Extension
.c
Size
1200 bytes
Lines
49
Domain
Representative Device Path
Bucket
PCIe NVMe Storage Path
Inferred role
Representative Device Path: implementation source
Status
source implementation candidate

Why This File Exists

Part of the selected hardware vertical slice: PCI discovery, driver binding, NVMe queues, block requests, DMA, interrupts, and completion.

Dependency Surface

Detected Declarations

Annotated Snippet

struct ultrix_disklabel {
		s32	pt_magic;	/* magic no. indicating part. info exits */
		s32	pt_valid;	/* set by driver if pt is current */
		struct  pt_info {
			s32		pi_nblocks; /* no. of sectors */
			u32		pi_blkoff;  /* block offset for start */
		} pt_part[8];
	} *label;

#define PT_MAGIC	0x032957	/* Partition magic number */
#define PT_VALID	1		/* Indicates if struct is valid */

	data = read_part_sector(state, (16384 - sizeof(*label))/512, &sect);
	if (!data)
		return -1;
	
	label = (struct ultrix_disklabel *)(data + 512 - sizeof(*label));

	if (label->pt_magic == PT_MAGIC && label->pt_valid == PT_VALID) {
		for (i=0; i<8; i++)
			if (label->pt_part[i].pi_nblocks)
				put_partition(state, i+1, 
					      label->pt_part[i].pi_blkoff,
					      label->pt_part[i].pi_nblocks);
		put_dev_sector(sect);
		seq_buf_puts(&state->pp_buf, "\n");
		return 1;
	} else {
		put_dev_sector(sect);
		return 0;
	}
}

Annotation

Implementation Notes