From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5EC85155321 for ; Mon, 29 Jul 2024 13:45:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722260747; cv=none; b=QVK111+PtggEx66wVKC7Ll9gjd7EUZM5GabivrYXIBmYMqj7KrTRftDp8dhAQJbyaWIZviSR3fQGFar0e+Lbqozy8KRlRwMknDxjGH/8wMLT4vf+V+tPvFYVX2z3z+9VskJY+JrCIucnxCe1u0CAVIfnUSJl4j7r0N5ZKKbICz8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722260747; c=relaxed/simple; bh=g+s5zWQ+1bjLhV5trF8N1eSvfylYTcdt0aXRUvyr3B0=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=bOv/TqP+6wLVvdx6pSJeWrNeaqJ4vXLxFM3KcE0Ly/PcDZLggMW/HnlUJ9XkemMly3mbv0a2hBn0ibt66svslTAYe35cIHzwolIHzrcN4NJ1Gxqwn1KVrtsr3EM3a2lgv6vkJiTlNlkN4Y/1XFg5h6Alpq55Xt8gnbOPTDP9I1g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=M1u88upd; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="M1u88upd" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1722260744; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to; bh=doSH2GJ4WKzw7yVJQbebYQerdG+8934K9oPj26npbuU=; b=M1u88updFriU2VK++qzNLCUwFpPdi851MmcJsPRK2i58wf45ISGzcfmyhKoMUAz+rG4+H0 goq36NFGBWvumeAEofgSBoueyDxkaIuNQLecGrPNjOujyVZqZM0PPFn3llzWudLIxI2Fqy qEMrZlrDtLaLOaGfw3TyPvtiZIBAnR4= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-176-S4zvsVJjOqKQOqNNjQG5bA-1; Mon, 29 Jul 2024 09:45:40 -0400 X-MC-Unique: S4zvsVJjOqKQOqNNjQG5bA-1 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A296B1955D4A; Mon, 29 Jul 2024 13:45:38 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.225.232]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id E5D3019560AE; Mon, 29 Jul 2024 13:45:35 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 29 Jul 2024 15:45:39 +0200 (CEST) Date: Mon, 29 Jul 2024 15:45:35 +0200 From: Oleg Nesterov To: andrii@kernel.org, mhiramat@kernel.org, peterz@infradead.org Cc: jolsa@kernel.org, rostedt@goodmis.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH v2 5/5] uprobes: make uprobe_register() return struct uprobe * Message-ID: <20240729134535.GA12332@redhat.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240729134444.GA12293@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 This way uprobe_unregister() and uprobe_apply() can use "struct uprobe *" rather than inode + offset. This simplifies the code and allows to avoid the unnecessary find_uprobe() + put_uprobe() in these functions. TODO: uprobe_unregister() still needs get_uprobe/put_uprobe to ensure that this uprobe can't be freed before up_write(&uprobe->register_rwsem). Signed-off-by: Oleg Nesterov Acked-by: Andrii Nakryiko --- include/linux/uprobes.h | 15 +++++----- kernel/events/uprobes.c | 56 +++++++++++++++---------------------- kernel/trace/bpf_trace.c | 25 ++++++++--------- kernel/trace/trace_uprobe.c | 26 ++++++++--------- 4 files changed, 55 insertions(+), 67 deletions(-) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 440316fbf3c6..137ddfc0b2f8 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -16,6 +16,7 @@ #include #include +struct uprobe; struct vm_area_struct; struct mm_struct; struct inode; @@ -110,9 +111,9 @@ extern bool is_trap_insn(uprobe_opcode_t *insn); extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs); extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs); extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t); -extern int uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc); -extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool); -extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc); +extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc); +extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool); +extern void uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *uc); extern int uprobe_mmap(struct vm_area_struct *vma); extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end); extern void uprobe_start_dup_mmap(void); @@ -150,18 +151,18 @@ static inline void uprobes_init(void) #define uprobe_get_trap_addr(regs) instruction_pointer(regs) -static inline int +static inline struct uprobe * uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc) { - return -ENOSYS; + return ERR_PTR(-ENOSYS); } static inline int -uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool add) +uprobe_apply(struct uprobe* uprobe, struct uprobe_consumer *uc, bool add) { return -ENOSYS; } static inline void -uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc) +uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *uc) { } static inline int uprobe_mmap(struct vm_area_struct *vma) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index b7f40bad8abc..974474680820 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1099,20 +1099,14 @@ __uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *uc) delete_uprobe(uprobe); } -/* +/** * uprobe_unregister - unregister an already registered probe. - * @inode: the file in which the probe has to be removed. - * @offset: offset from the start of the file. + * @uprobe: uprobe to remove * @uc: identify which probe if multiple probes are colocated. */ -void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc) +void uprobe_unregister(struct uprobe *uprobe, struct uprobe_consumer *uc) { - struct uprobe *uprobe; - - uprobe = find_uprobe(inode, offset); - if (WARN_ON(!uprobe)) - return; - + get_uprobe(uprobe); down_write(&uprobe->register_rwsem); __uprobe_unregister(uprobe, uc); up_write(&uprobe->register_rwsem); @@ -1120,7 +1114,7 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume } EXPORT_SYMBOL_GPL(uprobe_unregister); -/* +/** * uprobe_register - register a probe * @inode: the file in which the probe has to be placed. * @offset: offset from the start of the file. @@ -1136,40 +1130,40 @@ EXPORT_SYMBOL_GPL(uprobe_unregister); * unregisters. Caller of uprobe_register() is required to keep @inode * (and the containing mount) referenced. * - * Return errno if it cannot successully install probes - * else return 0 (success) + * Return: pointer to the new uprobe on success or an ERR_PTR on failure. */ -int uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, - struct uprobe_consumer *uc) +struct uprobe *uprobe_register(struct inode *inode, + loff_t offset, loff_t ref_ctr_offset, + struct uprobe_consumer *uc) { struct uprobe *uprobe; int ret; /* Uprobe must have at least one set consumer */ if (!uc->handler && !uc->ret_handler) - return -EINVAL; + return ERR_PTR(-EINVAL); /* copy_insn() uses read_mapping_page() or shmem_read_mapping_page() */ if (!inode->i_mapping->a_ops->read_folio && !shmem_mapping(inode->i_mapping)) - return -EIO; + return ERR_PTR(-EIO); /* Racy, just to catch the obvious mistakes */ if (offset > i_size_read(inode)) - return -EINVAL; + return ERR_PTR(-EINVAL); /* * This ensures that copy_from_page(), copy_to_page() and * __update_ref_ctr() can't cross page boundary. */ if (!IS_ALIGNED(offset, UPROBE_SWBP_INSN_SIZE)) - return -EINVAL; + return ERR_PTR(-EINVAL); if (!IS_ALIGNED(ref_ctr_offset, sizeof(short))) - return -EINVAL; + return ERR_PTR(-EINVAL); retry: uprobe = alloc_uprobe(inode, offset, ref_ctr_offset); if (IS_ERR(uprobe)) - return PTR_ERR(uprobe); + return uprobe; /* * We can race with uprobe_unregister()->delete_uprobe(). @@ -1188,35 +1182,29 @@ int uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, if (unlikely(ret == -EAGAIN)) goto retry; - return ret; + + return ret ? ERR_PTR(ret) : uprobe; } EXPORT_SYMBOL_GPL(uprobe_register); -/* - * uprobe_apply - unregister an already registered probe. - * @inode: the file in which the probe has to be removed. - * @offset: offset from the start of the file. +/** + * uprobe_apply - add or remove the breakpoints according to @uc->filter + * @uprobe: uprobe which "owns" the breakpoint * @uc: consumer which wants to add more or remove some breakpoints * @add: add or remove the breakpoints + * Return: 0 on success or negative error code. */ -int uprobe_apply(struct inode *inode, loff_t offset, - struct uprobe_consumer *uc, bool add) +int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool add) { - struct uprobe *uprobe; struct uprobe_consumer *con; int ret = -ENOENT; - uprobe = find_uprobe(inode, offset); - if (WARN_ON(!uprobe)) - return ret; - down_write(&uprobe->register_rwsem); for (con = uprobe->consumers; con && con != uc ; con = con->next) ; if (con) ret = register_for_each_vma(uprobe, add ? uc : NULL); up_write(&uprobe->register_rwsem); - put_uprobe(uprobe); return ret; } diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index afa909e17824..4e391daafa64 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3160,6 +3160,7 @@ struct bpf_uprobe { loff_t offset; unsigned long ref_ctr_offset; u64 cookie; + struct uprobe *uprobe; struct uprobe_consumer consumer; }; @@ -3178,15 +3179,12 @@ struct bpf_uprobe_multi_run_ctx { struct bpf_uprobe *uprobe; }; -static void bpf_uprobe_unregister(struct path *path, struct bpf_uprobe *uprobes, - u32 cnt) +static void bpf_uprobe_unregister(struct bpf_uprobe *uprobes, u32 cnt) { u32 i; - for (i = 0; i < cnt; i++) { - uprobe_unregister(d_real_inode(path->dentry), uprobes[i].offset, - &uprobes[i].consumer); - } + for (i = 0; i < cnt; i++) + uprobe_unregister(uprobes[i].uprobe, &uprobes[i].consumer); } static void bpf_uprobe_multi_link_release(struct bpf_link *link) @@ -3194,7 +3192,7 @@ static void bpf_uprobe_multi_link_release(struct bpf_link *link) struct bpf_uprobe_multi_link *umulti_link; umulti_link = container_of(link, struct bpf_uprobe_multi_link, link); - bpf_uprobe_unregister(&umulti_link->path, umulti_link->uprobes, umulti_link->cnt); + bpf_uprobe_unregister(umulti_link->uprobes, umulti_link->cnt); if (umulti_link->task) put_task_struct(umulti_link->task); path_put(&umulti_link->path); @@ -3480,12 +3478,13 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr &bpf_uprobe_multi_link_lops, prog); for (i = 0; i < cnt; i++) { - err = uprobe_register(d_real_inode(link->path.dentry), - uprobes[i].offset, - uprobes[i].ref_ctr_offset, - &uprobes[i].consumer); - if (err) { - bpf_uprobe_unregister(&path, uprobes, i); + uprobes[i].uprobe = uprobe_register(d_real_inode(link->path.dentry), + uprobes[i].offset, + uprobes[i].ref_ctr_offset, + &uprobes[i].consumer); + if (IS_ERR(uprobes[i].uprobe)) { + err = PTR_ERR(uprobes[i].uprobe); + bpf_uprobe_unregister(uprobes, i); goto error_free; } } diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 1f590f989c1e..52e76a73fa7c 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -58,8 +58,8 @@ struct trace_uprobe { struct dyn_event devent; struct uprobe_consumer consumer; struct path path; - struct inode *inode; char *filename; + struct uprobe *uprobe; unsigned long offset; unsigned long ref_ctr_offset; unsigned long nhit; @@ -1084,16 +1084,16 @@ typedef bool (*filter_func_t)(struct uprobe_consumer *self, static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter) { - int ret; + struct inode *inode = d_real_inode(tu->path.dentry); + struct uprobe *uprobe; tu->consumer.filter = filter; - tu->inode = d_real_inode(tu->path.dentry); - - ret = uprobe_register(tu->inode, tu->offset, tu->ref_ctr_offset, &tu->consumer); - if (ret) - tu->inode = NULL; + uprobe = uprobe_register(inode, tu->offset, tu->ref_ctr_offset, &tu->consumer); + if (IS_ERR(uprobe)) + return PTR_ERR(uprobe); - return ret; + tu->uprobe = uprobe; + return 0; } static void __probe_event_disable(struct trace_probe *tp) @@ -1104,11 +1104,11 @@ static void __probe_event_disable(struct trace_probe *tp) WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter)); list_for_each_entry(tu, trace_probe_probe_list(tp), tp.list) { - if (!tu->inode) + if (!tu->uprobe) continue; - uprobe_unregister(tu->inode, tu->offset, &tu->consumer); - tu->inode = NULL; + uprobe_unregister(tu->uprobe, &tu->consumer); + tu->uprobe = NULL; } } @@ -1305,7 +1305,7 @@ static int uprobe_perf_close(struct trace_event_call *call, return 0; list_for_each_entry(tu, trace_probe_probe_list(tp), tp.list) { - ret = uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); + ret = uprobe_apply(tu->uprobe, &tu->consumer, false); if (ret) break; } @@ -1329,7 +1329,7 @@ static int uprobe_perf_open(struct trace_event_call *call, return 0; list_for_each_entry(tu, trace_probe_probe_list(tp), tp.list) { - err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); + err = uprobe_apply(tu->uprobe, &tu->consumer, true); if (err) { uprobe_perf_close(call, event); break; -- 2.25.1.362.g51ebf55