X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=probes%2Flttng-uprobes.c;h=64d8237ca6eac2cbbc1c07df5f976dc7dd45367c;hb=HEAD;hp=0b399291245f9f38d4ce1f52931311ebada3d73a;hpb=7445d54f4034116e7276c23c414ea019c5466472;p=lttng-modules.git diff --git a/probes/lttng-uprobes.c b/probes/lttng-uprobes.c deleted file mode 100644 index 0b399291..00000000 --- a/probes/lttng-uprobes.c +++ /dev/null @@ -1,262 +0,0 @@ -/* - * probes/lttng-uprobes.c - * - * LTTng uprobes integration module. - * - * Copyright (C) 2013 Yannick Brosseau - * Copyright (C) 2009-2012 Mathieu Desnoyers - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; only - * version 2.1 of the License. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -static -int lttng_uprobes_handler_pre(struct uprobe_consumer *uc, struct pt_regs *regs) -{ - struct lttng_uprobe_handler *uprobe_handler = - container_of(uc, struct lttng_uprobe_handler, up_consumer); - struct lttng_event *event = uprobe_handler->event; - struct lttng_probe_ctx lttng_probe_ctx = { - .event = event, - .interruptible = !lttng_regs_irqs_disabled(regs), - }; - struct lttng_channel *chan = event->chan; - struct lib_ring_buffer_ctx ctx; - int ret; - - struct { - unsigned long ip; - } payload; - - if (unlikely(!ACCESS_ONCE(chan->session->active))) - return 0; - if (unlikely(!ACCESS_ONCE(chan->enabled))) - return 0; - if (unlikely(!ACCESS_ONCE(event->enabled))) - return 0; - - lib_ring_buffer_ctx_init(&ctx, chan->chan, <tng_probe_ctx, - sizeof(payload), lttng_alignof(payload), -1); - - ret = chan->ops->event_reserve(&ctx, event->id); - if (ret < 0) - return 0; - - /* Event payload. */ - payload.ip = (unsigned long)instruction_pointer(regs); - - lib_ring_buffer_align_ctx(&ctx, lttng_alignof(payload)); - chan->ops->event_write(&ctx, &payload, sizeof(payload)); - chan->ops->event_commit(&ctx); - return 0; -} - -/* - * Create event description. - */ -static -int lttng_create_uprobe_event(const char *name, struct lttng_event *event) -{ - struct lttng_event_desc *desc; - struct lttng_event_field *fields; - int ret; - - desc = kzalloc(sizeof(*event->desc), GFP_KERNEL); - if (!desc) - return -ENOMEM; - desc->name = kstrdup(name, GFP_KERNEL); - if (!desc->name) { - ret = -ENOMEM; - goto error_str; - } - - desc->nr_fields = 1; - desc->fields = fields = - kzalloc(1 * sizeof(struct lttng_event_field), GFP_KERNEL); - - if (!desc->fields) { - ret = -ENOMEM; - goto error_fields; - } - fields[0].name = "ip"; - fields[0].type.atype = atype_integer; - fields[0].type.u.basic.integer.size = sizeof(unsigned long) * CHAR_BIT; - fields[0].type.u.basic.integer.alignment = lttng_alignof(unsigned long) * CHAR_BIT; - fields[0].type.u.basic.integer.signedness = lttng_is_signed_type(unsigned long); - fields[0].type.u.basic.integer.reverse_byte_order = 0; - fields[0].type.u.basic.integer.base = 16; - fields[0].type.u.basic.integer.encoding = lttng_encode_none; - - desc->owner = THIS_MODULE; - event->desc = desc; - - return 0; - -error_fields: - kfree(desc->name); -error_str: - kfree(desc); - return ret; -} - -/* - * Returns the inode struct from the current task and an fd. The inode is - * grabbed by this function and must be put once we are done with it using - * iput(). - */ -static struct inode *get_inode_from_fd(int fd) -{ - struct file *file; - struct inode *inode; - - rcu_read_lock(); - /* - * Returns the file backing the given fd. Needs to be done inside an RCU - * critical section. - */ - file = fcheck(fd); - if (file == NULL) { - printk(KERN_WARNING "Cannot access file backing the fd(%d)\n", fd); - inode = NULL; - goto error; - } - - /* Grab a reference on the inode. */ - inode = igrab(file->f_path.dentry->d_inode); - if (inode == NULL) - printk(KERN_WARNING "Cannot grab a reference on the inode.\n"); -error: - rcu_read_unlock(); - return inode; -} - -int lttng_uprobes_add_callsite(struct lttng_event *event, - struct lttng_kernel_event_callsite __user *callsite) -{ - int ret = 0; - struct lttng_uprobe_handler *uprobe_handler; - - if (!event) { - ret = -EINVAL; - goto end; - } - - uprobe_handler = kzalloc(sizeof(struct lttng_uprobe_handler), GFP_KERNEL); - if (!uprobe_handler) { - printk(KERN_WARNING "Error allocating uprobe_uprobe_handlers"); - ret = -ENOMEM; - goto end; - } - - /* Ensure the memory we just allocated don't trigger page faults. */ - wrapper_vmalloc_sync_all(); - - uprobe_handler->event = event; - uprobe_handler->up_consumer.handler = lttng_uprobes_handler_pre; - - ret = copy_from_user(&uprobe_handler->offset, &callsite->u.uprobe.offset, sizeof(uint64_t)); - if (ret) { - goto register_error; - } - - ret = wrapper_uprobe_register(event->u.uprobe.inode, - uprobe_handler->offset, &uprobe_handler->up_consumer); - if (ret) { - printk(KERN_WARNING "Error registering probe on inode %lu " - "and offset 0x%llx\n", event->u.uprobe.inode->i_ino, - uprobe_handler->offset); - ret = -1; - goto register_error; - } - - list_add(&uprobe_handler->node, &event->u.uprobe.head); - - return ret; - -register_error: - kfree(uprobe_handler); -end: - return ret; -} -EXPORT_SYMBOL_GPL(lttng_uprobes_add_callsite); - -int lttng_uprobes_register(const char *name, int fd, struct lttng_event *event) -{ - int ret = 0; - struct inode *inode; - - ret = lttng_create_uprobe_event(name, event); - if (ret) - goto error; - - inode = get_inode_from_fd(fd); - if (!inode) { - printk(KERN_WARNING "Cannot get inode from fd\n"); - ret = -EBADF; - goto inode_error; - } - event->u.uprobe.inode = inode; - INIT_LIST_HEAD(&event->u.uprobe.head); - - return 0; - -inode_error: - kfree(event->desc->name); - kfree(event->desc); -error: - return ret; -} -EXPORT_SYMBOL_GPL(lttng_uprobes_register); - -void lttng_uprobes_unregister(struct lttng_event *event) -{ - struct lttng_uprobe_handler *iter, *tmp; - - /* - * Iterate over the list of handler, remove each handler from the list - * and free the struct. - */ - list_for_each_entry_safe(iter, tmp, &event->u.uprobe.head, node) { - wrapper_uprobe_unregister(event->u.uprobe.inode, iter->offset, - &iter->up_consumer); - list_del(&iter->node); - kfree(iter); - } -} -EXPORT_SYMBOL_GPL(lttng_uprobes_unregister); - -void lttng_uprobes_destroy_private(struct lttng_event *event) -{ - iput(event->u.uprobe.inode); - kfree(event->desc->name); - kfree(event->desc); -} -EXPORT_SYMBOL_GPL(lttng_uprobes_destroy_private); - -MODULE_LICENSE("GPL and additional rights"); -MODULE_AUTHOR("Yannick Brosseau"); -MODULE_DESCRIPTION("Linux Trace Toolkit Uprobes Support");