diff options
Diffstat (limited to 'drivers/android/binder.c')
| -rw-r--r-- | drivers/android/binder.c | 3760 |
1 files changed, 2502 insertions, 1258 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 831cdd7d197d..d055b3f2a207 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -15,6 +15,40 @@ * */ +/* + * Locking overview + * + * There are 3 main spinlocks which must be acquired in the + * order shown: + * + * 1) proc->outer_lock : protects binder_ref + * binder_proc_lock() and binder_proc_unlock() are + * used to acq/rel. + * 2) node->lock : protects most fields of binder_node. + * binder_node_lock() and binder_node_unlock() are + * used to acq/rel + * 3) proc->inner_lock : protects the thread and node lists + * (proc->threads, proc->waiting_threads, proc->nodes) + * and all todo lists associated with the binder_proc + * (proc->todo, thread->todo, proc->delivered_death and + * node->async_todo), as well as thread->transaction_stack + * binder_inner_proc_lock() and binder_inner_proc_unlock() + * are used to acq/rel + * + * Any lock under procA must never be nested under any lock at the same + * level or below on procB. + * + * Functions that require a lock held on entry indicate which lock + * in the suffix of the function name: + * + * foo_olocked() : requires node->outer_lock + * foo_nlocked() : requires node->lock + * foo_ilocked() : requires proc->inner_lock + * foo_oilocked(): requires proc->outer_lock and proc->inner_lock + * foo_nilocked(): requires node->lock and proc->inner_lock + * ... + */ + #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <asm/cacheflush.h> @@ -24,7 +58,6 @@ #include <linux/fs.h> #include <linux/list.h> #include <linux/miscdevice.h> -#include <linux/mm.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/nsproxy.h> @@ -35,30 +68,31 @@ #include <linux/sched/mm.h> #include <linux/seq_file.h> #include <linux/uaccess.h> -#include <linux/vmalloc.h> -#include <linux/slab.h> #include <linux/pid_namespace.h> #include <linux/security.h> +#include <linux/spinlock.h> #ifdef CONFIG_ANDROID_BINDER_IPC_32BIT #define BINDER_IPC_32BIT 1 #endif #include <uapi/linux/android/binder.h> +#include "binder_alloc.h" #include "binder_trace.h" -static DEFINE_MUTEX(binder_main_lock); +static HLIST_HEAD(binder_deferred_list); static DEFINE_MUTEX(binder_deferred_lock); -static DEFINE_MUTEX(binder_mmap_lock); static HLIST_HEAD(binder_devices); static HLIST_HEAD(binder_procs); -static HLIST_HEAD(binder_deferred_list); +static DEFINE_MUTEX(binder_procs_lock); + static HLIST_HEAD(binder_dead_nodes); +static DEFINE_SPINLOCK(binder_dead_nodes_lock); static struct dentry *binder_debugfs_dir_entry_root; static struct dentry *binder_debugfs_dir_entry_proc; -static int binder_last_id; +static atomic_t binder_last_id; #define BINDER_DEBUG_ENTRY(name) \ static int binder_##name##_open(struct inode *inode, struct file *file) \ @@ -88,8 +122,6 @@ BINDER_DEBUG_ENTRY(proc); #define FORBIDDEN_MMAP_FLAGS (VM_WRITE) -#define BINDER_SMALL_BUF_SIZE (PAGE_SIZE * 64) - enum { BINDER_DEBUG_USER_ERROR = 1U << 0, BINDER_DEBUG_FAILED_TRANSACTION = 1U << 1, @@ -104,17 +136,13 @@ enum { BINDER_DEBUG_TRANSACTION_COMPLETE = 1U << 10, BINDER_DEBUG_FREE_BUFFER = 1U << 11, BINDER_DEBUG_INTERNAL_REFS = 1U << 12, - BINDER_DEBUG_BUFFER_ALLOC = 1U << 13, - BINDER_DEBUG_PRIORITY_CAP = 1U << 14, - BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 15, + BINDER_DEBUG_PRIORITY_CAP = 1U << 13, + BINDER_DEBUG_SPINLOCKS = 1U << 14, }; static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR | BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION; module_param_named(debug_mask, binder_debug_mask, uint, S_IWUSR | S_IRUGO); -static bool binder_debug_no_lock; -module_param_named(proc_no_lock, binder_debug_no_lock, bool, S_IWUSR | S_IRUGO); - static char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; module_param_named(devices, binder_devices_param, charp, 0444); @@ -171,26 +199,27 @@ enum binder_stat_types { }; struct binder_stats { - int br[_IOC_NR(BR_FAILED_REPLY) + 1]; - int bc[_IOC_NR(BC_REPLY_SG) + 1]; - int obj_created[BINDER_STAT_COUNT]; - int obj_deleted[BINDER_STAT_COUNT]; + atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1]; + atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; + atomic_t obj_created[BINDER_STAT_COUNT]; + atomic_t obj_deleted[BINDER_STAT_COUNT]; }; static struct binder_stats binder_stats; static inline void binder_stats_deleted(enum binder_stat_types type) { - binder_stats.obj_deleted[type]++; + atomic_inc(&binder_stats.obj_deleted[type]); } static inline void binder_stats_created(enum binder_stat_types type) { - binder_stats.obj_created[type]++; + atomic_inc(&binder_stats.obj_created[type]); } struct binder_transaction_log_entry { int debug_id; + int debug_id_done; int call_type; int from_proc; int from_thread; @@ -200,11 +229,14 @@ struct binder_transaction_log_entry { int to_node; int data_size; int offsets_size; + int return_error_line; + uint32_t return_error; + uint32_t return_error_param; const char *context_name; }; struct binder_transaction_log { - int next; - int full; + atomic_t cur; + bool full; struct binder_transaction_log_entry entry[32]; }; static struct binder_transaction_log binder_transaction_log; @@ -214,19 +246,26 @@ static struct binder_transaction_log_entry *binder_transaction_log_add( struct binder_transaction_log *log) { struct binder_transaction_log_entry *e; + unsigned int cur = atomic_inc_return(&log->cur); - e = &log->entry[log->next]; - memset(e, 0, sizeof(*e)); - log->next++; - if (log->next == ARRAY_SIZE(log->entry)) { - log->next = 0; + if (cur >= ARRAY_SIZE(log->entry)) log->full = 1; - } + e = &log->entry[cur % ARRAY_SIZE(log->entry)]; + WRITE_ONCE(e->debug_id_done, 0); + /* + * write-barrier to synchronize access to e->debug_id_done. + * We make sure the initialized 0 value is seen before + * memset() other fields are zeroed by memset. + */ + smp_wmb(); + memset(e, 0, sizeof(*e)); return e; } struct binder_context { struct binder_node *binder_context_mgr_node; + struct mutex context_mgr_node_lock; + kuid_t binder_context_mgr_uid; const char *name; }; @@ -237,11 +276,20 @@ struct binder_device { struct binder_context context; }; +/** + * struct binder_work - work enqueued on a worklist + * @entry: node enqueued on list + * @type: type of work to be performed + * + * There are separate work lists for proc, thread, and node (async). + */ struct binder_work { struct list_head entry; + enum { BINDER_WORK_TRANSACTION = 1, BINDER_WORK_TRANSACTION_COMPLETE, + BINDER_WORK_RETURN_ERROR, BINDER_WORK_NODE, BINDER_WORK_DEAD_BINDER, BINDER_WORK_DEAD_BINDER_AND_CLEAR, @@ -249,8 +297,72 @@ struct binder_work { } type; }; +struct binder_error { + struct binder_work work; + uint32_t cmd; +}; + +/** + * struct binder_node - binder node bookkeeping + * @debug_id: unique ID for debugging + * (invariant after initialized) + * @lock: lock for node fields + * @work: worklist element for node work + * (protected by @proc->inner_lock) + * @rb_node: element for proc->nodes tree + * (protected by @proc->inner_lock) + * @dead_node: element for binder_dead_nodes list + * (protected by binder_dead_nodes_lock) + * @proc: binder_proc that owns this node + * (invariant after initialized) + * @refs: list of references on this node + * (protected by @lock) + * @internal_strong_refs: used to take strong references when + * initiating a transaction + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_weak_refs: weak user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_strong_refs: strong user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @tmp_refs: temporary kernel refs + * (protected by @proc->inner_lock while @proc + * is valid, and by binder_dead_nodes_lock + * if @proc is NULL. During inc/dec and node release + * it is also protected by @lock to provide safety + * as the node dies and @proc becomes NULL) + * @ptr: userspace pointer for node + * (invariant, no lock needed) + * @cookie: userspace cookie for node + * (invariant, no lock needed) + * @has_strong_ref: userspace notified of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_strong_ref: userspace has acked notification of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_weak_ref: userspace notified of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_weak_ref: userspace has acked notification of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_async_transaction: async transaction to node in progress + * (protected by @lock) + * @accept_fds: file descriptor operations supported for node + * (invariant after initialized) + * @min_priority: minimum scheduling priority + * (invariant after initialized) + * @async_todo: list of async work items + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder nodes. + */ struct binder_node { int debug_id; + spinlock_t lock; struct binder_work work; union { struct rb_node rb_node; @@ -261,88 +373,167 @@ struct binder_node { int internal_strong_refs; int local_weak_refs; int local_strong_refs; + int tmp_refs; binder_uintptr_t ptr; binder_uintptr_t cookie; - unsigned has_strong_ref:1; - unsigned pending_strong_ref:1; - unsigned has_weak_ref:1; - unsigned pending_weak_ref:1; - unsigned has_async_transaction:1; - unsigned accept_fds:1; - unsigned min_priority:8; + struct { + /* + * bitfield elements protected by + * proc inner_lock + */ + u8 has_strong_ref:1; + u8 pending_strong_ref:1; + u8 has_weak_ref:1; + u8 pending_weak_ref:1; + }; + struct { + /* + * invariant after initialization + */ + u8 accept_fds:1; + u8 min_priority; + }; + bool has_async_transaction; struct list_head async_todo; }; struct binder_ref_death { + /** + * @work: worklist element for death notifications + * (protected by inner_lock of the proc that + * this ref belongs to) + */ struct binder_work work; binder_uintptr_t cookie; }; +/** + * struct binder_ref_data - binder_ref counts and id + * @debug_id: unique ID for the ref + * @desc: unique userspace handle for ref + * @strong: strong ref count (debugging only if not locked) + * @weak: weak ref count (debugging only if not locked) + * + * Structure to hold ref count and ref id information. Since + * the actual ref can only be accessed with a lock, this structure + * is used to return information about the ref to callers of + * ref inc/dec functions. + */ +struct binder_ref_data { + int debug_id; + uint32_t desc; + int strong; + int weak; +}; + +/** + * struct binder_ref - struct to track references on nodes + * @data: binder_ref_data containing id, handle, and current refcounts + * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree + * @rb_node_node: node for lookup by @node in proc's rb_tree + * @node_entry: list entry for node->refs list in target node + * (protected by @node->lock) + * @proc: binder_proc containing ref + * @node: binder_node of target node. When cleaning up a + * ref for deletion in binder_cleanup_ref, a non-NULL + * @node indicates the node must be freed + * @death: pointer to death notification (ref_death) if requested + * (protected by @node->lock) + * + * Structure to track references from procA to target node (on procB). This + * structure is unsafe to access without holding @proc->outer_lock. + */ struct binder_ref { /* Lookups needed: */ /* node + proc => ref (transaction) */ /* desc + proc => ref (transaction, inc/dec ref) */ /* node => refs + procs (proc exit) */ - int debug_id; + struct binder_ref_data data; struct rb_node rb_node_desc; struct rb_node rb_node_node; struct hlist_node node_entry; struct binder_proc *proc; struct binder_node *node; - uint32_t desc; - int strong; - int weak; struct binder_ref_death *death; }; -struct binder_buffer { - struct list_head entry; /* free and allocated entries by address */ - struct rb_node rb_node; /* free entry by size or allocated entry */ - /* by address */ - unsigned free:1; - unsigned allow_user_free:1; - unsigned async_transaction:1; - unsigned debug_id:29; - - struct binder_transaction *transaction; - - struct binder_node *target_node; - size_t data_size; - size_t offsets_size; - size_t extra_buffers_size; - uint8_t data[0]; -}; - enum binder_deferred_state { BINDER_DEFERRED_PUT_FILES = 0x01, BINDER_DEFERRED_FLUSH = 0x02, BINDER_DEFERRED_RELEASE = 0x04, }; +/** + * struct binder_proc - binder process bookkeeping + * @proc_node: element for binder_procs list + * @threads: rbtree of binder_threads in this proc + * (protected by @inner_lock) + * @nodes: rbtree of binder nodes associated with + * this proc ordered by node->ptr + * (protected by @inner_lock) + * @refs_by_desc: rbtree of refs ordered by ref->desc + * (protected by @outer_lock) + * @refs_by_node: rbtree of refs ordered by ref->node + * (protected by @outer_lock) + * @waiting_threads: threads currently waiting for proc work + * (protected by @inner_lock) + * @pid PID of group_leader of process + * (invariant after initialized) + * @tsk task_struct for group_leader of process + * (invariant after initialized) + * @files files_struct for process + * (invariant after initialized) + * @deferred_work_node: element for binder_deferred_list + * (protected by binder_deferred_lock) + * @deferred_work: bitmap of deferred work to perform + * (protected by binder_deferred_lock) + * @is_dead: process is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @inner_lock) + * @todo: list of work for this process + * (protected by @inner_lock) + * @wait: wait queue head to wait for proc work + * (invariant after initialized) + * @stats: per-process binder statistics + * (atomics, no lock needed) + * @delivered_death: list of delivered death notification + * (protected by @inner_lock) + * @max_threads: cap on number of binder threads + * (protected by @inner_lock) + * @requested_threads: number of binder threads requested but not + * yet started. In current implementation, can + * only be 0 or 1. + * (protected by @inner_lock) + * @requested_threads_started: number binder threads started + * (protected by @inner_lock) + * @tmp_ref: temporary reference to indicate proc is in use + * (protected by @inner_lock) + * @default_priority: default scheduler priority + * (invariant after initialized) + * @debugfs_entry: debugfs node + * @alloc: binder allocator bookkeeping + * @context: binder_context for this proc + * (invariant after initialized) + * @inner_lock: can nest under outer_lock and/or node lock + * @outer_lock: no nesting under innor or node lock + * Lock order: 1) outer, 2) node, 3) inner + * + * Bookkeeping structure for binder processes + */ struct binder_proc { struct hlist_node proc_node; struct rb_root threads; struct rb_root nodes; struct rb_root refs_by_desc; struct rb_root refs_by_node; + struct list_head waiting_threads; int pid; - struct vm_area_struct *vma; - struct mm_struct *vma_vm_mm; struct task_struct *tsk; struct files_struct *files; struct hlist_node deferred_work_node; int deferred_work; - void *buffer; - ptrdiff_t user_buffer_offset; - - struct list_head buffers; - struct rb_root free_buffers; - struct rb_root allocated_buffers; - size_t free_async_space; + bool is_dead; - struct page **pages; - size_t buffer_size; - uint32_t buffer_free; struct list_head todo; wait_queue_head_t wait; struct binder_stats stats; @@ -350,10 +541,13 @@ struct binder_proc { int max_threads; int requested_threads; int requested_threads_started; - int ready_threads; + int tmp_ref; long default_priority; struct dentry *debugfs_entry; + struct binder_alloc alloc; struct binder_context *context; + spinlock_t inner_lock; + spinlock_t outer_lock; }; enum { @@ -362,22 +556,58 @@ enum { BINDER_LOOPER_STATE_EXITED = 0x04, BINDER_LOOPER_STATE_INVALID = 0x08, BINDER_LOOPER_STATE_WAITING = 0x10, - BINDER_LOOPER_STATE_NEED_RETURN = 0x20 + BINDER_LOOPER_STATE_POLL = 0x20, }; +/** + * struct binder_thread - binder thread bookkeeping + * @proc: binder process for this thread + * (invariant after initialization) + * @rb_node: element for proc->threads rbtree + * (protected by @proc->inner_lock) + * @waiting_thread_node: element for @proc->waiting_threads list + * (protected by @proc->inner_lock) + * @pid: PID for this thread + * (invariant after initialization) + * @looper: bitmap of looping state + * (only accessed by this thread) + * @looper_needs_return: looping thread needs to exit driver + * (no lock needed) + * @transaction_stack: stack of in-progress transactions for this thread + * (protected by @proc->inner_lock) + * @todo: list of work to do for this thread + * (protected by @proc->inner_lock) + * @return_error: transaction errors reported by this thread + * (only accessed by this thread) + * @reply_error: transaction errors reported by target thread + * (protected by @proc->inner_lock) + * @wait: wait queue for thread work + * @stats: per-thread statistics + * (atomics, no lock needed) + * @tmp_ref: temporary reference to indicate thread is in use + * (atomic since @proc->inner_lock cannot + * always be acquired) + * @is_dead: thread is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder threads. + */ struct binder_thread { struct binder_proc *proc; struct rb_node rb_node; + struct list_head waiting_thread_node; int pid; - int looper; + int looper; /* only modified by this thread */ + bool looper_need_return; /* can be written by other thread */ struct binder_transaction *transaction_stack; struct list_head todo; - uint32_t return_error; /* Write failed, return error code in read buf */ - uint32_t return_error2; /* Write failed, return error code in read */ - /* buffer. Used when sending a reply to a dead process that */ - /* we are also waiting on */ + struct binder_error return_error; + struct binder_error reply_error; wait_queue_head_t wait; struct binder_stats stats; + atomic_t tmp_ref; + bool is_dead; }; struct binder_transaction { @@ -397,10 +627,253 @@ struct binder_transaction { long priority; long saved_priority; kuid_t sender_euid; + /** + * @lock: protects @from, @to_proc, and @to_thread + * + * @from, @to_proc, and @to_thread can be set to NULL + * during thread teardown + */ + spinlock_t lock; }; +/** + * binder_proc_lock() - Acquire outer lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->outer_lock. Used to protect binder_ref + * structures associated with the given proc. + */ +#define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__) +static void +_binder_proc_lock(struct binder_proc *proc, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->outer_lock); +} + +/** + * binder_proc_unlock() - Release spinlock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_proc_lock() + */ +#define binder_proc_unlock(_proc) _binder_proc_unlock(_proc, __LINE__) +static void +_binder_proc_unlock(struct binder_proc *proc, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->outer_lock); +} + +/** + * binder_inner_proc_lock() - Acquire inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->inner_lock. Used to protect todo lists + */ +#define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__) +static void +_binder_inner_proc_lock(struct binder_proc *proc, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->inner_lock); +} + +/** + * binder_inner_proc_unlock() - Release inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_inner_proc_lock() + */ +#define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__) +static void +_binder_inner_proc_unlock(struct binder_proc *proc, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->inner_lock); +} + +/** + * binder_node_lock() - Acquire spinlock for given binder_node + * @node: struct binder_node to acquire + * + * Acquires node->lock. Used to protect binder_node fields + */ +#define binder_node_lock(node) _binder_node_lock(node, __LINE__) +static void +_binder_node_lock(struct binder_node *node, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); +} + +/** + * binder_node_unlock() - Release spinlock for given binder_proc + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_unlock(node) _binder_node_unlock(node, __LINE__) +static void +_binder_node_unlock(struct binder_node *node, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&node->lock); +} + +/** + * binder_node_inner_lock() - Acquire node and inner locks + * @node: struct binder_node to acquire + * + * Acquires node->lock. If node->proc also acquires + * proc->inner_lock. Used to protect binder_node fields + */ +#define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__) +static void +_binder_node_inner_lock(struct binder_node *node, int line) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); + if (node->proc) + binder_inner_proc_lock(node->proc); +} + +/** + * binder_node_unlock() - Release node and inner locks + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__) +static void +_binder_node_inner_unlock(struct binder_node *node, int line) +{ + struct binder_proc *proc = node->proc; + + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + if (proc) + binder_inner_proc_unlock(proc); + spin_unlock(&node->lock); +} + +static bool binder_worklist_empty_ilocked(struct list_head *list) +{ + return list_empty(list); +} + +/** + * binder_worklist_empty() - Check if no items on the work list + * @proc: binder_proc associated with list + * @list: list to check + * + * Return: true if there are no items on list, else false + */ +static bool binder_worklist_empty(struct binder_proc *proc, + struct list_head *list) +{ + bool ret; + + binder_inner_proc_lock(proc); + ret = binder_worklist_empty_ilocked(list); + binder_inner_proc_unlock(proc); + return ret; +} + +static void +binder_enqueue_work_ilocked(struct binder_work *work, + struct list_head *target_list) +{ + BUG_ON(target_list == NULL); + BUG_ON(work->entry.next && !list_empty(&work->entry)); + list_add_tail(&work->entry, target_list); +} + +/** + * binder_enqueue_work() - Add an item to the work list + * @proc: binder_proc associated with list + * @work: struct binder_work to add to list + * @target_list: list to add work to + * + * Adds the work to the specified list. Asserts that work + * is not already on a list. + */ +static void +binder_enqueue_work(struct binder_proc *proc, + struct binder_work *work, + struct list_head *target_list) +{ + binder_inner_proc_lock(proc); + binder_enqueue_work_ilocked(work, target_list); + binder_inner_proc_unlock(proc); +} + +static void +binder_dequeue_work_ilocked(struct binder_work *work) +{ + list_del_init(&work->entry); +} + +/** + * binder_dequeue_work() - Removes an item from the work list + * @proc: binder_proc associated with list + * @work: struct binder_work to remove from list + * + * Removes the specified work item from whatever list it is on. + * Can safely be called if work is not on any list. + */ +static void +binder_dequeue_work(struct binder_proc *proc, struct binder_work *work) +{ + binder_inner_proc_lock(proc); + binder_dequeue_work_ilocked(work); + binder_inner_proc_unlock(proc); +} + +static struct binder_work *binder_dequeue_work_head_ilocked( + struct list_head *list) +{ + struct binder_work *w; + + w = list_first_entry_or_null(list, struct binder_work, entry); + if (w) + list_del_init(&w->entry); + return w; +} + +/** + * binder_dequeue_work_head() - Dequeues the item at head of list + * @proc: binder_proc associated with list + * @list: list to dequeue head + * + * Removes the head of the list if there are items on the list + * + * Return: pointer dequeued binder_work, NULL if list was empty + */ +static struct binder_work *binder_dequeue_work_head( + struct binder_proc *proc, + struct list_head *list) +{ + struct binder_work *w; + + binder_inner_proc_lock(proc); + w = binder_dequeue_work_head_ilocked(list); + binder_inner_proc_unlock(proc); + return w; +} + static void binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer); +static void binder_free_thread(struct binder_thread *thread); +static void binder_free_proc(struct binder_proc *proc); +static void binder_inc_node_tmpref_ilocked(struct binder_node *node); static int task_get_unused_fd_flags(struct binder_proc *proc, int flags) { @@ -451,462 +924,159 @@ static long task_close_fd(struct binder_proc *proc, unsigned int fd) return retval; } -static inline void binder_lock(const char *tag) -{ - trace_binder_lock(tag); - mutex_lock(&binder_main_lock); - trace_binder_locked(tag); -} - -static inline void binder_unlock(const char *tag) -{ - trace_binder_unlock(tag); - mutex_unlock(&binder_main_lock); -} - -static void binder_set_nice(long nice) -{ - long min_nice; - - if (can_nice(current, nice)) { - set_user_nice(current, nice); - return; - } - min_nice = rlimit_to_nice(current->signal->rlim[RLIMIT_NICE].rlim_cur); - binder_debug(BINDER_DEBUG_PRIORITY_CAP, - "%d: nice value %ld not allowed use %ld instead\n", - current->pid, nice, min_nice); - set_user_nice(current, min_nice); - if (min_nice <= MAX_NICE) - return; - binder_user_error("%d RLIMIT_NICE not set\n", current->pid); -} - -static size_t binder_buffer_size(struct binder_proc *proc, - struct binder_buffer *buffer) +static bool binder_has_work_ilocked(struct binder_thread *thread, + bool do_proc_work) { - if (list_is_last(&buffer->entry, &proc->buffers)) - return proc->buffer + proc->buffer_size - (void *)buffer->data; - return (size_t)list_entry(buffer->entry.next, - struct binder_buffer, entry) - (size_t)buffer->data; + return !binder_worklist_empty_ilocked(&thread->todo) || + thread->looper_need_return || + (do_proc_work && + !binder_worklist_empty_ilocked(&thread->proc->todo)); } -static void binder_insert_free_buffer(struct binder_proc *proc, - struct binder_buffer *new_buffer) +static bool binder_has_work(struct binder_thread *thread, bool do_proc_work) { - struct rb_node **p = &proc->free_buffers.rb_node; - struct rb_node *parent = NULL; - struct binder_buffer *buffer; - size_t buffer_size; - size_t new_buffer_size; + bool has_work; - BUG_ON(!new_buffer->free); + binder_inner_proc_lock(thread->proc); + has_work = binder_has_work_ilocked(thread, do_proc_work); + binder_inner_proc_unlock(thread->proc); - new_buffer_size = binder_buffer_size(proc, new_buffer); - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: add free buffer, size %zd, at %p\n", - proc->pid, new_buffer_size, new_buffer); - - while (*p) { - parent = *p; - buffer = rb_entry(parent, struct binder_buffer, rb_node); - BUG_ON(!buffer->free); - - buffer_size = binder_buffer_size(proc, buffer); - - if (new_buffer_size < buffer_size) - p = &parent->rb_left; - else - p = &parent->rb_right; - } - rb_link_node(&new_buffer->rb_node, parent, p); - rb_insert_color(&new_buffer->rb_node, &proc->free_buffers); + return has_work; } -static void binder_insert_allocated_buffer(struct binder_proc *proc, - struct binder_buffer *new_buffer) +static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread) { - struct rb_node **p = &proc->allocated_buffers.rb_node; - struct rb_node *parent = NULL; - struct binder_buffer *buffer; - - BUG_ON(new_buffer->free); - - while (*p) { - parent = *p; - buffer = rb_entry(parent, struct binder_buffer, rb_node); - BUG_ON(buffer->free); - - if (new_buffer < buffer) - p = &parent->rb_left; - else if (new_buffer > buffer) - p = &parent->rb_right; - else - BUG(); - } - rb_link_node(&new_buffer->rb_node, parent, p); - rb_insert_color(&new_buffer->rb_node, &proc->allocated_buffers); + return !thread->transaction_stack && + binder_worklist_empty_ilocked(&thread->todo) && + (thread->looper & (BINDER_LOOPER_STATE_ENTERED | + BINDER_LOOPER_STATE_REGISTERED)); } -static struct binder_buffer *binder_buffer_lookup(struct binder_proc *proc, - uintptr_t user_ptr) +static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc, + bool sync) { - struct rb_node *n = proc->allocated_buffers.rb_node; - struct binder_buffer *buffer; - struct binder_buffer *kern_ptr; - - kern_ptr = (struct binder_buffer *)(user_ptr - proc->user_buffer_offset - - offsetof(struct binder_buffer, data)); - - while (n) { - buffer = rb_entry(n, struct binder_buffer, rb_node); - BUG_ON(buffer->free); + struct rb_node *n; + struct binder_thread *thread; - if (kern_ptr < buffer) - n = n->rb_left; - else if (kern_ptr > buffer) - n = n->rb_right; - else - return buffer; + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) { + thread = rb_entry(n, struct binder_thread, rb_node); + if (thread->looper & BINDER_LOOPER_STATE_POLL && + binder_available_for_proc_work_ilocked(thread)) { + if (sync) + wake_up_interruptible_sync(&thread->wait); + else + wake_up_interruptible(&thread->wait); + } } - return NULL; } -static int binder_update_page_range(struct binder_proc *proc, int allocate, - void *start, void *end, - struct vm_area_struct *vma) +/** + * binder_select_thread_ilocked() - selects a thread for doing proc work. + * @proc: process to select a thread from + * + * Note that calling this function moves the thread off the waiting_threads + * list, so it can only be woken up by the caller of this function, or a + * signal. Therefore, callers *should* always wake up the thread this function + * returns. + * + * Return: If there's a thread currently waiting for process work, + * returns that thread. Otherwise returns NULL. + */ +static struct binder_thread * +binder_select_thread_ilocked(struct binder_proc *proc) { - void *page_addr; - unsigned long user_page_addr; - struct page **page; - struct mm_struct *mm; - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: %s pages %p-%p\n", proc->pid, - allocate ? "allocate" : "free", start, end); - - if (end <= start) - return 0; - - trace_binder_update_page_range(proc, allocate, start, end); - - if (vma) - mm = NULL; - else - mm = get_task_mm(proc->tsk); - - if (mm) { - down_write(&mm->mmap_sem); - vma = proc->vma; - if (vma && mm != proc->vma_vm_mm) { - pr_err("%d: vma mm and task mm mismatch\n", - proc->pid); - vma = NULL; - } - } - - if (allocate == 0) - goto free_range; - - if (vma == NULL) { - pr_err("%d: binder_alloc_buf failed to map pages in userspace, no vma\n", - proc->pid); - goto err_no_vma; - } - - for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { - int ret; + struct binder_thread *thread; - page = &proc->pages[(page_addr - proc->buffer) / PAGE_SIZE]; + assert_spin_locked(&proc->inner_lock); + thread = list_first_entry_or_null(&proc->waiting_threads, + struct binder_thread, |