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| author | Al Viro <viro@zeniv.linux.org.uk> | 2024-07-31 11:49:04 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2024-10-07 13:34:41 -0400 |
| commit | 8fd3395ec9051a52828fcca2328cb50a69dea8ef (patch) | |
| tree | d68b2a86f57af48fbece1070a3d3a09fc16a7521 /fs/notify | |
| parent | Linux 6.12-rc2 (diff) | |
| download | linux-8fd3395ec9051a52828fcca2328cb50a69dea8ef.tar.gz linux-8fd3395ec9051a52828fcca2328cb50a69dea8ef.zip | |
get rid of ...lookup...fdget_rcu() family
Once upon a time, predecessors of those used to do file lookup
without bumping a refcount, provided that caller held rcu_read_lock()
across the lookup and whatever it wanted to read from the struct
file found. When struct file allocation switched to SLAB_TYPESAFE_BY_RCU,
that stopped being feasible and these primitives started to bump the
file refcount for lookup result, requiring the caller to call fput()
afterwards.
But that turned them pointless - e.g.
rcu_read_lock();
file = lookup_fdget_rcu(fd);
rcu_read_unlock();
is equivalent to
file = fget_raw(fd);
and all callers of lookup_fdget_rcu() are of that form. Similarly,
task_lookup_fdget_rcu() calls can be replaced with calling fget_task().
task_lookup_next_fdget_rcu() doesn't have direct counterparts, but
its callers would be happier if we replaced it with an analogue that
deals with RCU internally.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/notify')
| -rw-r--r-- | fs/notify/dnotify/dnotify.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c index d5dbef7f5c95..6004dfdfdf0f 100644 --- a/fs/notify/dnotify/dnotify.c +++ b/fs/notify/dnotify/dnotify.c @@ -16,7 +16,6 @@ #include <linux/security.h> #include <linux/spinlock.h> #include <linux/slab.h> -#include <linux/fdtable.h> #include <linux/fsnotify_backend.h> static int dir_notify_enable __read_mostly = 1; @@ -347,9 +346,7 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned int arg) new_fsn_mark = NULL; } - rcu_read_lock(); - f = lookup_fdget_rcu(fd); - rcu_read_unlock(); + f = fget_raw(fd); /* if (f != filp) means that we lost a race and another task/thread * actually closed the fd we are still playing with before we grabbed |