diff options
Diffstat (limited to 'fs/locks.c')
| -rw-r--r-- | fs/locks.c | 119 |
1 files changed, 61 insertions, 58 deletions
diff --git a/fs/locks.c b/fs/locks.c index 9f565802a88cd3..e75c8084d937be 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -369,10 +369,19 @@ locks_dispose_list(struct list_head *dispose) while (!list_empty(dispose)) { flc = list_first_entry(dispose, struct file_lock_core, flc_list); list_del_init(&flc->flc_list); - if (flc->flc_flags & (FL_LEASE|FL_DELEG|FL_LAYOUT)) - locks_free_lease(file_lease(flc)); - else - locks_free_lock(file_lock(flc)); + locks_free_lock(file_lock(flc)); + } +} + +static void +lease_dispose_list(struct list_head *dispose) +{ + struct file_lock_core *flc; + + while (!list_empty(dispose)) { + flc = list_first_entry(dispose, struct file_lock_core, flc_list); + list_del_init(&flc->flc_list); + locks_free_lease(file_lease(flc)); } } @@ -576,10 +585,50 @@ lease_setup(struct file_lease *fl, void **priv) __f_setown(filp, task_pid(current), PIDTYPE_TGID, 0); } +/** + * lease_open_conflict - see if the given file points to an inode that has + * an existing open that would conflict with the + * desired lease. + * @filp: file to check + * @arg: type of lease that we're trying to acquire + * + * Check to see if there's an existing open fd on this file that would + * conflict with the lease we're trying to set. + */ +static int +lease_open_conflict(struct file *filp, const int arg) +{ + struct inode *inode = file_inode(filp); + int self_wcount = 0, self_rcount = 0; + + if (arg == F_RDLCK) + return inode_is_open_for_write(inode) ? -EAGAIN : 0; + else if (arg != F_WRLCK) + return 0; + + /* + * Make sure that only read/write count is from lease requestor. + * Note that this will result in denying write leases when i_writecount + * is negative, which is what we want. (We shouldn't grant write leases + * on files open for execution.) + */ + if (filp->f_mode & FMODE_WRITE) + self_wcount = 1; + else if (filp->f_mode & FMODE_READ) + self_rcount = 1; + + if (atomic_read(&inode->i_writecount) != self_wcount || + atomic_read(&inode->i_readcount) != self_rcount) + return -EAGAIN; + + return 0; +} + static const struct lease_manager_operations lease_manager_ops = { .lm_break = lease_break_callback, .lm_change = lease_modify, .lm_setup = lease_setup, + .lm_open_conflict = lease_open_conflict, }; /* @@ -1620,7 +1669,7 @@ restart: spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); error = wait_event_interruptible_timeout(new_fl->c.flc_wait, list_empty(&new_fl->c.flc_blocked_member), break_time); @@ -1643,7 +1692,7 @@ restart: out: spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); free_lock: locks_free_lease(new_fl); return error; @@ -1727,7 +1776,7 @@ static int __fcntl_getlease(struct file *filp, unsigned int flavor) spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); } return type; } @@ -1745,52 +1794,6 @@ int fcntl_getdeleg(struct file *filp, struct delegation *deleg) return 0; } -/** - * check_conflicting_open - see if the given file points to an inode that has - * an existing open that would conflict with the - * desired lease. - * @filp: file to check - * @arg: type of lease that we're trying to acquire - * @flags: current lock flags - * - * Check to see if there's an existing open fd on this file that would - * conflict with the lease we're trying to set. - */ -static int -check_conflicting_open(struct file *filp, const int arg, int flags) -{ - struct inode *inode = file_inode(filp); - int self_wcount = 0, self_rcount = 0; - - if (flags & FL_LAYOUT) - return 0; - if (flags & FL_DELEG) - /* We leave these checks to the caller */ - return 0; - - if (arg == F_RDLCK) - return inode_is_open_for_write(inode) ? -EAGAIN : 0; - else if (arg != F_WRLCK) - return 0; - - /* - * Make sure that only read/write count is from lease requestor. - * Note that this will result in denying write leases when i_writecount - * is negative, which is what we want. (We shouldn't grant write leases - * on files open for execution.) - */ - if (filp->f_mode & FMODE_WRITE) - self_wcount = 1; - else if (filp->f_mode & FMODE_READ) - self_rcount = 1; - - if (atomic_read(&inode->i_writecount) != self_wcount || - atomic_read(&inode->i_readcount) != self_rcount) - return -EAGAIN; - - return 0; -} - static int generic_add_lease(struct file *filp, int arg, struct file_lease **flp, void **priv) { @@ -1827,7 +1830,7 @@ generic_add_lease(struct file *filp, int arg, struct file_lease **flp, void **pr percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); - error = check_conflicting_open(filp, arg, lease->c.flc_flags); + error = lease->fl_lmops->lm_open_conflict(filp, arg); if (error) goto out; @@ -1884,7 +1887,7 @@ generic_add_lease(struct file *filp, int arg, struct file_lease **flp, void **pr * precedes these checks. */ smp_mb(); - error = check_conflicting_open(filp, arg, lease->c.flc_flags); + error = lease->fl_lmops->lm_open_conflict(filp, arg); if (error) { locks_unlink_lock_ctx(&lease->c); goto out; @@ -1896,7 +1899,7 @@ out_setup: out: spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); if (is_deleg) inode_unlock(inode); if (!error && !my_fl) @@ -1932,7 +1935,7 @@ static int generic_delete_lease(struct file *filp, void *owner) error = fl->fl_lmops->lm_change(victim, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); return error; } @@ -2727,7 +2730,7 @@ locks_remove_lease(struct file *filp, struct file_lock_context *ctx) spin_unlock(&ctx->flc_lock); percpu_up_read(&file_rwsem); - locks_dispose_list(&dispose); + lease_dispose_list(&dispose); } /* |
