fs/coda/upcall.c

File Facts

System

Linux kernel

Corpus path

fs/coda/upcall.c

Extension

.c

Size

24915 bytes

Lines

962

Domain

Core OS

Bucket

VFS And Filesystem Core

Inferred role

Core OS: implementation source

Status

source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

• Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/signal.h
• linux/sched/signal.h
• linux/types.h
• linux/kernel.h
• linux/mm.h
• linux/time.h
• linux/fs.h
• linux/file.h
• linux/stat.h
• linux/errno.h
• linux/string.h
• linux/slab.h
• linux/mutex.h
• linux/uaccess.h
• linux/vmalloc.h
• linux/vfs.h
• linux/coda.h
• coda_psdev.h
• coda_linux.h
• coda_cache.h
• coda_int.h

Detected Declarations

• function venus_rootfid
• function venus_getattr
• function venus_setattr
• function venus_lookup
• function venus_close
• function venus_open
• function venus_mkdir
• function venus_rename
• function venus_create
• function venus_rmdir
• function venus_remove
• function venus_readlink
• function venus_link
• function venus_symlink
• function venus_fsync
• function venus_access
• function venus_pioctl
• function venus_statfs
• function venus_access_intent
• function coda_block_signals
• function coda_unblock_signals
• function coda_waitfor_upcall
• function errors
• function coda_downcall

Annotated Snippet

if (IS_ERR(inp)) { return PTR_ERR(inp); }\
        outp = (union outputArgs *)(inp); \
        outsize = insize; \
} while (0)

#define INSIZE(tag) sizeof(struct coda_ ## tag ## _in)
#define OUTSIZE(tag) sizeof(struct coda_ ## tag ## _out)
#define SIZE(tag)  max_t(unsigned int, INSIZE(tag), OUTSIZE(tag))


/* the upcalls */
int venus_rootfid(struct super_block *sb, struct CodaFid *fidp)
{
        union inputArgs *inp;
        union outputArgs *outp;
        int insize, outsize, error;

        insize = SIZE(root);
        UPARG(CODA_ROOT);

	error = coda_upcall(coda_vcp(sb), insize, &outsize, inp);
	if (!error)
		*fidp = outp->coda_root.VFid;

	kvfree(inp);
	return error;
}

int venus_getattr(struct super_block *sb, struct CodaFid *fid, 
		     struct coda_vattr *attr) 
{
        union inputArgs *inp;
        union outputArgs *outp;
        int insize, outsize, error;

        insize = SIZE(getattr); 
	UPARG(CODA_GETATTR);
        inp->coda_getattr.VFid = *fid;

	error = coda_upcall(coda_vcp(sb), insize, &outsize, inp);
	if (!error)
		*attr = outp->coda_getattr.attr;

	kvfree(inp);
        return error;
}

int venus_setattr(struct super_block *sb, struct CodaFid *fid, 
		  struct coda_vattr *vattr)
{
        union inputArgs *inp;
        union outputArgs *outp;
        int insize, outsize, error;
	
	insize = SIZE(setattr);
	UPARG(CODA_SETATTR);

        inp->coda_setattr.VFid = *fid;
	inp->coda_setattr.attr = *vattr;

	error = coda_upcall(coda_vcp(sb), insize, &outsize, inp);

	kvfree(inp);
        return error;
}

int venus_lookup(struct super_block *sb, struct CodaFid *fid, 
		    const char *name, int length, int * type, 
		    struct CodaFid *resfid)
{
        union inputArgs *inp;
        union outputArgs *outp;
        int insize, outsize, error;
	int offset;

	offset = INSIZE(lookup);
        insize = max_t(unsigned int, offset + length +1, OUTSIZE(lookup));
	UPARG(CODA_LOOKUP);

        inp->coda_lookup.VFid = *fid;
	inp->coda_lookup.name = offset;
	inp->coda_lookup.flags = CLU_CASE_SENSITIVE;
        /* send Venus a null terminated string */
        memcpy((char *)(inp) + offset, name, length);
        *((char *)inp + offset + length) = '\0';

	error = coda_upcall(coda_vcp(sb), insize, &outsize, inp);
	if (!error) {
		*resfid = outp->coda_lookup.VFid;
		*type = outp->coda_lookup.vtype;

Annotation

• Immediate include surface: `linux/signal.h`, `linux/sched/signal.h`, `linux/types.h`, `linux/kernel.h`, `linux/mm.h`, `linux/time.h`, `linux/fs.h`, `linux/file.h`.
• Detected declarations: `function venus_rootfid`, `function venus_getattr`, `function venus_setattr`, `function venus_lookup`, `function venus_close`, `function venus_open`, `function venus_mkdir`, `function venus_rename`, `function venus_create`, `function venus_rmdir`.
• Atlas domain: Core OS / VFS And Filesystem Core.
• Implementation status: source implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.