locks: new locks_mandatory_area calling convention

Pass a loff_t end for the last byte instead of the 32-bit count
parameter to allow full file clones even on 32-bit architectures.
While we're at it also simplify the read/write selection.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig 2015-12-03 12:59:49 +01:00 committed by Al Viro
parent eac70053a1
commit acc15575e7
3 changed files with 25 additions and 32 deletions

View File

@ -1227,20 +1227,16 @@ int locks_mandatory_locked(struct file *file)
/**
* locks_mandatory_area - Check for a conflicting lock
* @read_write: %FLOCK_VERIFY_WRITE for exclusive access, %FLOCK_VERIFY_READ
* for shared
* @inode: the file to check
* @inode: the file to check
* @filp: how the file was opened (if it was)
* @offset: start of area to check
* @count: length of area to check
* @start: first byte in the file to check
* @end: lastbyte in the file to check
* @type: %F_WRLCK for a write lock, else %F_RDLCK
*
* Searches the inode's list of locks to find any POSIX locks which conflict.
* This function is called from rw_verify_area() and
* locks_verify_truncate().
*/
int locks_mandatory_area(int read_write, struct inode *inode,
struct file *filp, loff_t offset,
size_t count)
int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start,
loff_t end, unsigned char type)
{
struct file_lock fl;
int error;
@ -1252,9 +1248,9 @@ int locks_mandatory_area(int read_write, struct inode *inode,
fl.fl_flags = FL_POSIX | FL_ACCESS;
if (filp && !(filp->f_flags & O_NONBLOCK))
sleep = true;
fl.fl_type = (read_write == FLOCK_VERIFY_WRITE) ? F_WRLCK : F_RDLCK;
fl.fl_start = offset;
fl.fl_end = offset + count - 1;
fl.fl_type = type;
fl.fl_start = start;
fl.fl_end = end;
for (;;) {
if (filp) {

View File

@ -396,9 +396,8 @@ int rw_verify_area(int read_write, struct file *file, const loff_t *ppos, size_t
}
if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
retval = locks_mandatory_area(
read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE,
inode, file, pos, count);
retval = locks_mandatory_area(inode, file, pos, pos + count - 1,
read_write == READ ? F_RDLCK : F_WRLCK);
if (retval < 0)
return retval;
}

View File

@ -2030,12 +2030,9 @@ extern struct kobject *fs_kobj;
#define MAX_RW_COUNT (INT_MAX & PAGE_CACHE_MASK)
#define FLOCK_VERIFY_READ 1
#define FLOCK_VERIFY_WRITE 2
#ifdef CONFIG_FILE_LOCKING
extern int locks_mandatory_locked(struct file *);
extern int locks_mandatory_area(int, struct inode *, struct file *, loff_t, size_t);
extern int locks_mandatory_area(struct inode *, struct file *, loff_t, loff_t, unsigned char);
/*
* Candidates for mandatory locking have the setgid bit set
@ -2065,17 +2062,19 @@ static inline int locks_verify_locked(struct file *file)
}
static inline int locks_verify_truncate(struct inode *inode,
struct file *filp,
struct file *f,
loff_t size)
{
if (inode->i_flctx && mandatory_lock(inode))
return locks_mandatory_area(
FLOCK_VERIFY_WRITE, inode, filp,
size < inode->i_size ? size : inode->i_size,
(size < inode->i_size ? inode->i_size - size
: size - inode->i_size)
);
return 0;
if (!inode->i_flctx || !mandatory_lock(inode))
return 0;
if (size < inode->i_size) {
return locks_mandatory_area(inode, f, size, inode->i_size - 1,
F_WRLCK);
} else {
return locks_mandatory_area(inode, f, inode->i_size, size - 1,
F_WRLCK);
}
}
static inline int break_lease(struct inode *inode, unsigned int mode)
@ -2144,9 +2143,8 @@ static inline int locks_mandatory_locked(struct file *file)
return 0;
}
static inline int locks_mandatory_area(int rw, struct inode *inode,
struct file *filp, loff_t offset,
size_t count)
static inline int locks_mandatory_area(struct inode *inode, struct file *filp,
loff_t start, loff_t end, unsigned char type)
{
return 0;
}