mount

Implemented in Antinomie 0.7.0 · Syscall list

Synopsis

long mount(char *dev_name, char *dir_name, char *type, unsigned long flags, void *data);

Number (x86-64)	165
ABI	common
Kernel entry point	sys_mount

This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.

Description

Mounts a filesystem, or changes an existing mount, at a directory.

Arguments

Name	Type	Meaning
dev_name (arg0)	char *	Device or source name.
dir_name (arg1)	char *	Mount point directory.
type (arg2)	char *	Filesystem type name, such as ext4 or tmpfs.
flags (arg3)	unsigned long	MS_* mount flags.
data (arg4)	void *	Pointer to filesystem-specific option data, up to one page.

Return value

On success: 0.

In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.

Common errors

Raw return	Name	Meaning
-16	EBUSY	The resource is busy.
-22	EINVAL	An argument is invalid.
-19	ENODEV	There is no such device or filesystem type.
-1	EPERM	The operation is not permitted for this process.

Man page

mount(2) on man7.org

Captured by Antinomie

Coverage mark: Implemented. Every pointer argument has a capture rule in the pinned kernel patch and none of them records a “no decoder”, “address only” or “not observed” gap on any code path. Individual values can still be incomplete on a particular call; see the capture statuses.

Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).

Arguments

Argument	When	How	Recorded field key	Condition
dev_name (arg0)	Entry	the pointer itself, as a raw word	args.0, args.raw[0]
↳ pointee	Entry	NUL-terminated string, up to 4,096 bytes	arg0.dev_name	dev_name is not NULL
dir_name (arg1)	Entry	the pointer itself, as a raw word	args.1, args.raw[1]
↳ pointee	Entry	NUL-terminated string, up to 4,096 bytes	arg1.dir_name	always
type (arg2)	Entry	the pointer itself, as a raw word	args.2, args.raw[2]
↳ pointee	Entry	NUL-terminated string, up to 4,096 bytes	arg2.type	type is not NULL
flags (arg3)	Entry	raw scalar word; Syscall Trace also decodes it into flag names (mount group), listing unknown bits separately	args.3, args.flags
data (arg4)	Entry	the pointer itself, as a raw word	args.4, args.raw[4]
↳ pointee	Entry	the readable prefix of one page (layout mount_options); the rest of the page is arg4.data.tail with “copy fault” or “not resident”	arg4.data	data is not NULL

Family notes

• Entry only: dev_name, dir_name and type are strings up to 4,096 bytes; data is the readable prefix of one page (arg4.data), with an arg4.data.tail field when part of the page cannot be read.

Filter fields

• Result: ret, syscall.errno, syscall.success, syscall.duration_ns.
• Argument words: args.dev_name (arg0), args.dir_name (arg1), args.type (arg2), args.flags (arg3), args.data (arg4); args.0 to args.5 by position.
• Captured strings: the args.<name> field of a path argument, and args.path, give the captured text instead of the pointer.

See Syscall Trace filter for the full syntax.

For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.