From 53c0a58beb60b76e105a61aae518fd780eec03d9 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 25 May 2024 23:32:20 -0400 Subject: net/socket.c: switch to CLASS(fd) The important part in sockfd_lookup_light() is avoiding needless file refcount operations, not the marginal reduction of the register pressure from not keeping a struct file pointer in the caller. Switch to use fdget()/fdpu(); with sane use of CLASS(fd) we can get a better code generation... Would be nice if somebody tested it on networking test suites (including benchmarks)... sockfd_lookup_light() does fdget(), uses sock_from_file() to get the associated socket and returns the struct socket reference to the caller, along with "do we need to fput()" flag. No matching fdput(), the caller does its equivalent manually, using the fact that sock->file points to the struct file the socket has come from. Get rid of that - have the callers do fdget()/fdput() and use sock_from_file() directly. That kills sockfd_lookup_light() and fput_light() (no users left). What's more, we can get rid of explicit fdget()/fdput() by switching to CLASS(fd, ...) - code generation does not suffer, since now fdput() inserted on "descriptor is not opened" failure exit is recognized to be a no-op by compiler. [folded a fix for braino in do_recvmmsg() caught by Simon Horman] Reviewed-by: Christian Brauner Signed-off-by: Al Viro --- include/linux/file.h | 6 ------ 1 file changed, 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/file.h b/include/linux/file.h index f98de143245a..b49a92295b3f 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -30,12 +30,6 @@ extern struct file *alloc_file_pseudo_noaccount(struct inode *, struct vfsmount extern struct file *alloc_file_clone(struct file *, int flags, const struct file_operations *); -static inline void fput_light(struct file *file, int fput_needed) -{ - if (fput_needed) - fput(file); -} - /* either a reference to struct file + flags * (cloned vs. borrowed, pos locked), with * flags stored in lower bits of value, -- cgit v1.2.3 From f302edb9d822804e72df3fa6ba270234050c678b Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 14 Jul 2024 21:49:04 -0400 Subject: switch netlink_getsockbyfilp() to taking descriptor the only call site (in do_mq_notify()) obtains the argument from an immediately preceding fdget() and it is immediately followed by fdput(); might as well just replace it with a variant that would take a descriptor instead of struct file * and have file lookups handled inside that function. Reviewed-by: Christian Brauner Signed-off-by: Al Viro --- include/linux/netlink.h | 2 +- ipc/mqueue.c | 8 +------- net/netlink/af_netlink.c | 9 +++++++-- 3 files changed, 9 insertions(+), 10 deletions(-) (limited to 'include/linux') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index b332c2048c75..a48a30842d84 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -239,7 +239,7 @@ int netlink_register_notifier(struct notifier_block *nb); int netlink_unregister_notifier(struct notifier_block *nb); /* finegrained unicast helpers: */ -struct sock *netlink_getsockbyfilp(struct file *filp); +struct sock *netlink_getsockbyfd(int fd); int netlink_attachskb(struct sock *sk, struct sk_buff *skb, long *timeo, struct sock *ssk); void netlink_detachskb(struct sock *sk, struct sk_buff *skb); diff --git a/ipc/mqueue.c b/ipc/mqueue.c index 34fa0bd8bb11..fd05e3d4f7b6 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -1355,13 +1355,7 @@ static int do_mq_notify(mqd_t mqdes, const struct sigevent *notification) skb_put(nc, NOTIFY_COOKIE_LEN); /* and attach it to the socket */ retry: - f = fdget(notification->sigev_signo); - if (!fd_file(f)) { - ret = -EBADF; - goto out; - } - sock = netlink_getsockbyfilp(fd_file(f)); - fdput(f); + sock = netlink_getsockbyfd(notification->sigev_signo); if (IS_ERR(sock)) { ret = PTR_ERR(sock); goto free_skb; diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 0b7a89db3ab7..42451ac355d0 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1180,11 +1180,16 @@ static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) return sock; } -struct sock *netlink_getsockbyfilp(struct file *filp) +struct sock *netlink_getsockbyfd(int fd) { - struct inode *inode = file_inode(filp); + CLASS(fd, f)(fd); + struct inode *inode; struct sock *sock; + if (fd_empty(f)) + return ERR_PTR(-EBADF); + + inode = file_inode(fd_file(f)); if (!S_ISSOCK(inode->i_mode)) return ERR_PTR(-ENOTSOCK); -- cgit v1.2.3 From d7a9616ce0348b9d945d5dff82e4b44c0fe75b39 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Fri, 31 May 2024 22:10:12 -0400 Subject: introduce "fd_pos" class, convert fdget_pos() users to it. fdget_pos() for constructor, fdput_pos() for cleanup, all users of fd..._pos() converted trivially. Reviewed-by: Christian Brauner Signed-off-by: Al Viro --- arch/alpha/kernel/osf_sys.c | 5 ++--- fs/read_write.c | 34 +++++++++++++--------------------- fs/readdir.c | 28 ++++++++++------------------ include/linux/file.h | 1 + 4 files changed, 26 insertions(+), 42 deletions(-) (limited to 'include/linux') diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c index c0424de9e7cd..86185021f75a 100644 --- a/arch/alpha/kernel/osf_sys.c +++ b/arch/alpha/kernel/osf_sys.c @@ -152,7 +152,7 @@ SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd, long __user *, basep) { int error; - struct fd arg = fdget_pos(fd); + CLASS(fd_pos, arg)(fd); struct osf_dirent_callback buf = { .ctx.actor = osf_filldir, .dirent = dirent, @@ -160,7 +160,7 @@ SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd, .count = count }; - if (!fd_file(arg)) + if (fd_empty(arg)) return -EBADF; error = iterate_dir(fd_file(arg), &buf.ctx); @@ -169,7 +169,6 @@ SYSCALL_DEFINE4(osf_getdirentries, unsigned int, fd, if (count != buf.count) error = count - buf.count; - fdput_pos(arg); return error; } diff --git a/fs/read_write.c b/fs/read_write.c index 64dc24afdb3a..ef3ee3725714 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -386,8 +386,8 @@ EXPORT_SYMBOL(vfs_llseek); static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence) { off_t retval; - struct fd f = fdget_pos(fd); - if (!fd_file(f)) + CLASS(fd_pos, f)(fd); + if (fd_empty(f)) return -EBADF; retval = -EINVAL; @@ -397,7 +397,6 @@ static off_t ksys_lseek(unsigned int fd, off_t offset, unsigned int whence) if (res != (loff_t)retval) retval = -EOVERFLOW; /* LFS: should only happen on 32 bit platforms */ } - fdput_pos(f); return retval; } @@ -420,15 +419,14 @@ SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, unsigned int, whence) { int retval; - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); loff_t offset; - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; - retval = -EINVAL; if (whence > SEEK_MAX) - goto out_putf; + return -EINVAL; offset = vfs_llseek(fd_file(f), ((loff_t) offset_high << 32) | offset_low, whence); @@ -439,8 +437,6 @@ SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned long, offset_high, if (!copy_to_user(result, &offset, sizeof(offset))) retval = 0; } -out_putf: - fdput_pos(f); return retval; } #endif @@ -700,10 +696,10 @@ static inline loff_t *file_ppos(struct file *file) ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count) { - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); ssize_t ret = -EBADF; - if (fd_file(f)) { + if (!fd_empty(f)) { loff_t pos, *ppos = file_ppos(fd_file(f)); if (ppos) { pos = *ppos; @@ -712,7 +708,6 @@ ssize_t ksys_read(unsigned int fd, char __user *buf, size_t count) ret = vfs_read(fd_file(f), buf, count, ppos); if (ret >= 0 && ppos) fd_file(f)->f_pos = pos; - fdput_pos(f); } return ret; } @@ -724,10 +719,10 @@ SYSCALL_DEFINE3(read, unsigned int, fd, char __user *, buf, size_t, count) ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count) { - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); ssize_t ret = -EBADF; - if (fd_file(f)) { + if (!fd_empty(f)) { loff_t pos, *ppos = file_ppos(fd_file(f)); if (ppos) { pos = *ppos; @@ -736,7 +731,6 @@ ssize_t ksys_write(unsigned int fd, const char __user *buf, size_t count) ret = vfs_write(fd_file(f), buf, count, ppos); if (ret >= 0 && ppos) fd_file(f)->f_pos = pos; - fdput_pos(f); } return ret; @@ -1075,10 +1069,10 @@ out: static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen, rwf_t flags) { - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); ssize_t ret = -EBADF; - if (fd_file(f)) { + if (!fd_empty(f)) { loff_t pos, *ppos = file_ppos(fd_file(f)); if (ppos) { pos = *ppos; @@ -1087,7 +1081,6 @@ static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, ret = vfs_readv(fd_file(f), vec, vlen, ppos, flags); if (ret >= 0 && ppos) fd_file(f)->f_pos = pos; - fdput_pos(f); } if (ret > 0) @@ -1099,10 +1092,10 @@ static ssize_t do_readv(unsigned long fd, const struct iovec __user *vec, static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen, rwf_t flags) { - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); ssize_t ret = -EBADF; - if (fd_file(f)) { + if (!fd_empty(f)) { loff_t pos, *ppos = file_ppos(fd_file(f)); if (ppos) { pos = *ppos; @@ -1111,7 +1104,6 @@ static ssize_t do_writev(unsigned long fd, const struct iovec __user *vec, ret = vfs_writev(fd_file(f), vec, vlen, ppos, flags); if (ret >= 0 && ppos) fd_file(f)->f_pos = pos; - fdput_pos(f); } if (ret > 0) diff --git a/fs/readdir.c b/fs/readdir.c index 6d29cab8576e..0038efda417b 100644 --- a/fs/readdir.c +++ b/fs/readdir.c @@ -219,20 +219,19 @@ SYSCALL_DEFINE3(old_readdir, unsigned int, fd, struct old_linux_dirent __user *, dirent, unsigned int, count) { int error; - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); struct readdir_callback buf = { .ctx.actor = fillonedir, .dirent = dirent }; - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; error = iterate_dir(fd_file(f), &buf.ctx); if (buf.result) error = buf.result; - fdput_pos(f); return error; } @@ -309,7 +308,7 @@ efault: SYSCALL_DEFINE3(getdents, unsigned int, fd, struct linux_dirent __user *, dirent, unsigned int, count) { - struct fd f; + CLASS(fd_pos, f)(fd); struct getdents_callback buf = { .ctx.actor = filldir, .count = count, @@ -317,8 +316,7 @@ SYSCALL_DEFINE3(getdents, unsigned int, fd, }; int error; - f = fdget_pos(fd); - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; error = iterate_dir(fd_file(f), &buf.ctx); @@ -333,7 +331,6 @@ SYSCALL_DEFINE3(getdents, unsigned int, fd, else error = count - buf.count; } - fdput_pos(f); return error; } @@ -392,7 +389,7 @@ efault: SYSCALL_DEFINE3(getdents64, unsigned int, fd, struct linux_dirent64 __user *, dirent, unsigned int, count) { - struct fd f; + CLASS(fd_pos, f)(fd); struct getdents_callback64 buf = { .ctx.actor = filldir64, .count = count, @@ -400,8 +397,7 @@ SYSCALL_DEFINE3(getdents64, unsigned int, fd, }; int error; - f = fdget_pos(fd); - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; error = iterate_dir(fd_file(f), &buf.ctx); @@ -417,7 +413,6 @@ SYSCALL_DEFINE3(getdents64, unsigned int, fd, else error = count - buf.count; } - fdput_pos(f); return error; } @@ -477,20 +472,19 @@ COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd, struct compat_old_linux_dirent __user *, dirent, unsigned int, count) { int error; - struct fd f = fdget_pos(fd); + CLASS(fd_pos, f)(fd); struct compat_readdir_callback buf = { .ctx.actor = compat_fillonedir, .dirent = dirent }; - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; error = iterate_dir(fd_file(f), &buf.ctx); if (buf.result) error = buf.result; - fdput_pos(f); return error; } @@ -560,7 +554,7 @@ efault: COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, struct compat_linux_dirent __user *, dirent, unsigned int, count) { - struct fd f; + CLASS(fd_pos, f)(fd); struct compat_getdents_callback buf = { .ctx.actor = compat_filldir, .current_dir = dirent, @@ -568,8 +562,7 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, }; int error; - f = fdget_pos(fd); - if (!fd_file(f)) + if (fd_empty(f)) return -EBADF; error = iterate_dir(fd_file(f), &buf.ctx); @@ -584,7 +577,6 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, else error = count - buf.count; } - fdput_pos(f); return error; } #endif diff --git a/include/linux/file.h b/include/linux/file.h index b49a92295b3f..4b09a8de2fd5 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -81,6 +81,7 @@ static inline void fdput_pos(struct fd f) DEFINE_CLASS(fd, struct fd, fdput(_T), fdget(fd), int fd) DEFINE_CLASS(fd_raw, struct fd, fdput(_T), fdget_raw(fd), int fd) +DEFINE_CLASS(fd_pos, struct fd, fdput_pos(_T), fdget_pos(fd), int fd) extern int f_dupfd(unsigned int from, struct file *file, unsigned flags); extern int replace_fd(unsigned fd, struct file *file, unsigned flags); -- cgit v1.2.3 From 38052c2dd71f5490f34bba21dc358e97fb205ee5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 6 Jun 2024 19:29:04 -0400 Subject: deal with the last remaing boolean uses of fd_file() Reviewed-by: Christian Brauner Signed-off-by: Al Viro --- drivers/infiniband/core/uverbs_cmd.c | 8 +++----- include/linux/cleanup.h | 2 +- sound/core/pcm_native.c | 2 +- 3 files changed, 5 insertions(+), 7 deletions(-) (limited to 'include/linux') diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index a4cce360df21..66b02fbf077a 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -584,7 +584,7 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs) if (cmd.fd != -1) { /* search for file descriptor */ f = fdget(cmd.fd); - if (!fd_file(f)) { + if (fd_empty(f)) { ret = -EBADF; goto err_tree_mutex_unlock; } @@ -632,8 +632,7 @@ static int ib_uverbs_open_xrcd(struct uverbs_attr_bundle *attrs) atomic_inc(&xrcd->usecnt); } - if (fd_file(f)) - fdput(f); + fdput(f); mutex_unlock(&ibudev->xrcd_tree_mutex); uobj_finalize_uobj_create(&obj->uobject, attrs); @@ -648,8 +647,7 @@ err: uobj_alloc_abort(&obj->uobject, attrs); err_tree_mutex_unlock: - if (fd_file(f)) - fdput(f); + fdput(f); mutex_unlock(&ibudev->xrcd_tree_mutex); diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h index 038b2d523bf8..875c998275c0 100644 --- a/include/linux/cleanup.h +++ b/include/linux/cleanup.h @@ -234,7 +234,7 @@ const volatile void * __must_check_fn(const volatile void *val) * DEFINE_CLASS(fdget, struct fd, fdput(_T), fdget(fd), int fd) * * CLASS(fdget, f)(fd); - * if (!fd_file(f)) + * if (fd_empty(f)) * return -EBADF; * * // use 'f' without concern diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index b465fb6e1f5f..3320cce35a03 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -2250,7 +2250,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd) bool nonatomic = substream->pcm->nonatomic; CLASS(fd, f)(fd); - if (!fd_file(f)) + if (fd_empty(f)) return -EBADFD; if (!is_pcm_file(fd_file(f))) return -EBADFD; -- cgit v1.2.3