From f0c3b5093addc8bfe9fe3a5b01acb7ec7969eafa Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 16 May 2013 12:07:31 -0400 Subject: [readdir] convert procfs Signed-off-by: Al Viro --- fs/proc/base.c | 363 +++++++++++++++++++++------------------------------------ 1 file changed, 133 insertions(+), 230 deletions(-) (limited to 'fs/proc/base.c') diff --git a/fs/proc/base.c b/fs/proc/base.c index c3834da..0016350 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1681,11 +1681,11 @@ const struct dentry_operations pid_dentry_operations = * reported by readdir in sync with the inode numbers reported * by stat. */ -int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, +bool proc_fill_cache(struct file *file, struct dir_context *ctx, const char *name, int len, instantiate_t instantiate, struct task_struct *task, const void *ptr) { - struct dentry *child, *dir = filp->f_path.dentry; + struct dentry *child, *dir = file->f_path.dentry; struct inode *inode; struct qstr qname; ino_t ino = 0; @@ -1720,7 +1720,7 @@ end_instantiate: ino = find_inode_number(dir, &qname); if (!ino) ino = 1; - return filldir(dirent, name, len, filp->f_pos, ino, type); + return dir_emit(ctx, name, len, ino, type); } #ifdef CONFIG_CHECKPOINT_RESTORE @@ -1931,14 +1931,15 @@ static const struct inode_operations proc_map_files_inode_operations = { }; static int -proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir) +proc_map_files_readdir(struct file *file, struct dir_context *ctx) { - struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; struct vm_area_struct *vma; struct task_struct *task; struct mm_struct *mm; - ino_t ino; + unsigned long nr_files, pos, i; + struct flex_array *fa = NULL; + struct map_files_info info; + struct map_files_info *p; int ret; ret = -EPERM; @@ -1946,7 +1947,7 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir) goto out; ret = -ENOENT; - task = get_proc_task(inode); + task = get_proc_task(file_inode(file)); if (!task) goto out; @@ -1955,91 +1956,73 @@ proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir) goto out_put_task; ret = 0; - switch (filp->f_pos) { - case 0: - ino = inode->i_ino; - if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0) - goto out_put_task; - filp->f_pos++; - case 1: - ino = parent_ino(dentry); - if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) - goto out_put_task; - filp->f_pos++; - default: - { - unsigned long nr_files, pos, i; - struct flex_array *fa = NULL; - struct map_files_info info; - struct map_files_info *p; - - mm = get_task_mm(task); - if (!mm) - goto out_put_task; - down_read(&mm->mmap_sem); + if (!dir_emit_dots(file, ctx)) + goto out_put_task; - nr_files = 0; + mm = get_task_mm(task); + if (!mm) + goto out_put_task; + down_read(&mm->mmap_sem); - /* - * We need two passes here: - * - * 1) Collect vmas of mapped files with mmap_sem taken - * 2) Release mmap_sem and instantiate entries - * - * otherwise we get lockdep complained, since filldir() - * routine might require mmap_sem taken in might_fault(). - */ + nr_files = 0; - for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { - if (vma->vm_file && ++pos > filp->f_pos) - nr_files++; - } + /* + * We need two passes here: + * + * 1) Collect vmas of mapped files with mmap_sem taken + * 2) Release mmap_sem and instantiate entries + * + * otherwise we get lockdep complained, since filldir() + * routine might require mmap_sem taken in might_fault(). + */ - if (nr_files) { - fa = flex_array_alloc(sizeof(info), nr_files, - GFP_KERNEL); - if (!fa || flex_array_prealloc(fa, 0, nr_files, - GFP_KERNEL)) { - ret = -ENOMEM; - if (fa) - flex_array_free(fa); - up_read(&mm->mmap_sem); - mmput(mm); - goto out_put_task; - } - for (i = 0, vma = mm->mmap, pos = 2; vma; - vma = vma->vm_next) { - if (!vma->vm_file) - continue; - if (++pos <= filp->f_pos) - continue; - - info.mode = vma->vm_file->f_mode; - info.len = snprintf(info.name, - sizeof(info.name), "%lx-%lx", - vma->vm_start, vma->vm_end); - if (flex_array_put(fa, i++, &info, GFP_KERNEL)) - BUG(); - } + for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) { + if (vma->vm_file && ++pos > ctx->pos) + nr_files++; + } + + if (nr_files) { + fa = flex_array_alloc(sizeof(info), nr_files, + GFP_KERNEL); + if (!fa || flex_array_prealloc(fa, 0, nr_files, + GFP_KERNEL)) { + ret = -ENOMEM; + if (fa) + flex_array_free(fa); + up_read(&mm->mmap_sem); + mmput(mm); + goto out_put_task; } - up_read(&mm->mmap_sem); - - for (i = 0; i < nr_files; i++) { - p = flex_array_get(fa, i); - ret = proc_fill_cache(filp, dirent, filldir, - p->name, p->len, - proc_map_files_instantiate, - task, - (void *)(unsigned long)p->mode); - if (ret) - break; - filp->f_pos++; + for (i = 0, vma = mm->mmap, pos = 2; vma; + vma = vma->vm_next) { + if (!vma->vm_file) + continue; + if (++pos <= ctx->pos) + continue; + + info.mode = vma->vm_file->f_mode; + info.len = snprintf(info.name, + sizeof(info.name), "%lx-%lx", + vma->vm_start, vma->vm_end); + if (flex_array_put(fa, i++, &info, GFP_KERNEL)) + BUG(); } - if (fa) - flex_array_free(fa); - mmput(mm); } + up_read(&mm->mmap_sem); + + for (i = 0; i < nr_files; i++) { + p = flex_array_get(fa, i); + if (!proc_fill_cache(file, ctx, + p->name, p->len, + proc_map_files_instantiate, + task, + (void *)(unsigned long)p->mode)) + break; + ctx->pos++; } + if (fa) + flex_array_free(fa); + mmput(mm); out_put_task: put_task_struct(task); @@ -2049,7 +2032,7 @@ out: static const struct file_operations proc_map_files_operations = { .read = generic_read_dir, - .readdir = proc_map_files_readdir, + .iterate = proc_map_files_readdir, .llseek = default_llseek, }; @@ -2217,67 +2200,30 @@ out_no_task: return error; } -static int proc_pident_fill_cache(struct file *filp, void *dirent, - filldir_t filldir, struct task_struct *task, const struct pid_entry *p) -{ - return proc_fill_cache(filp, dirent, filldir, p->name, p->len, - proc_pident_instantiate, task, p); -} - -static int proc_pident_readdir(struct file *filp, - void *dirent, filldir_t filldir, +static int proc_pident_readdir(struct file *file, struct dir_context *ctx, const struct pid_entry *ents, unsigned int nents) { - int i; - struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; - struct task_struct *task = get_proc_task(inode); - const struct pid_entry *p, *last; - ino_t ino; - int ret; + struct task_struct *task = get_proc_task(file_inode(file)); + const struct pid_entry *p; - ret = -ENOENT; if (!task) - goto out_no_task; + return -ENOENT; - ret = 0; - i = filp->f_pos; - switch (i) { - case 0: - ino = inode->i_ino; - if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) - goto out; - i++; - filp->f_pos++; - /* fall through */ - case 1: - ino = parent_ino(dentry); - if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) - goto out; - i++; - filp->f_pos++; - /* fall through */ - default: - i -= 2; - if (i >= nents) { - ret = 1; - goto out; - } - p = ents + i; - last = &ents[nents - 1]; - while (p <= last) { - if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) - goto out; - filp->f_pos++; - p++; - } - } + if (!dir_emit_dots(file, ctx)) + goto out; + + if (ctx->pos >= nents + 2) + goto out; - ret = 1; + for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) { + if (!proc_fill_cache(file, ctx, p->name, p->len, + proc_pident_instantiate, task, p)) + break; + ctx->pos++; + } out: put_task_struct(task); -out_no_task: - return ret; + return 0; } #ifdef CONFIG_SECURITY @@ -2362,16 +2308,15 @@ static const struct pid_entry attr_dir_stuff[] = { REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), }; -static int proc_attr_dir_readdir(struct file * filp, - void * dirent, filldir_t filldir) +static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx) { - return proc_pident_readdir(filp,dirent,filldir, - attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); + return proc_pident_readdir(file, ctx, + attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); } static const struct file_operations proc_attr_dir_operations = { .read = generic_read_dir, - .readdir = proc_attr_dir_readdir, + .iterate = proc_attr_dir_readdir, .llseek = default_llseek, }; @@ -2725,16 +2670,15 @@ static const struct pid_entry tgid_base_stuff[] = { #endif }; -static int proc_tgid_base_readdir(struct file * filp, - void * dirent, filldir_t filldir) +static int proc_tgid_base_readdir(struct file *file, struct dir_context *ctx) { - return proc_pident_readdir(filp,dirent,filldir, - tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); + return proc_pident_readdir(file, ctx, + tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); } static const struct file_operations proc_tgid_base_operations = { .read = generic_read_dir, - .readdir = proc_tgid_base_readdir, + .iterate = proc_tgid_base_readdir, .llseek = default_llseek, }; @@ -2936,58 +2880,42 @@ retry: #define TGID_OFFSET (FIRST_PROCESS_ENTRY + 1) -static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, - struct tgid_iter iter) -{ - char name[PROC_NUMBUF]; - int len = snprintf(name, sizeof(name), "%d", iter.tgid); - return proc_fill_cache(filp, dirent, filldir, name, len, - proc_pid_instantiate, iter.task, NULL); -} - -static int fake_filldir(void *buf, const char *name, int namelen, - loff_t offset, u64 ino, unsigned d_type) -{ - return 0; -} - /* for the /proc/ directory itself, after non-process stuff has been done */ -int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) +int proc_pid_readdir(struct file *file, struct dir_context *ctx) { struct tgid_iter iter; struct pid_namespace *ns; - filldir_t __filldir; - loff_t pos = filp->f_pos; + loff_t pos = ctx->pos; if (pos >= PID_MAX_LIMIT + TGID_OFFSET) - goto out; + return 0; if (pos == TGID_OFFSET - 1) { - if (proc_fill_cache(filp, dirent, filldir, "self", 4, - NULL, NULL, NULL) < 0) - goto out; + if (!proc_fill_cache(file, ctx, "self", 4, NULL, NULL, NULL)) + return 0; iter.tgid = 0; } else { iter.tgid = pos - TGID_OFFSET; } iter.task = NULL; - ns = filp->f_dentry->d_sb->s_fs_info; + ns = file->f_dentry->d_sb->s_fs_info; for (iter = next_tgid(ns, iter); iter.task; iter.tgid += 1, iter = next_tgid(ns, iter)) { - if (has_pid_permissions(ns, iter.task, 2)) - __filldir = filldir; - else - __filldir = fake_filldir; + char name[PROC_NUMBUF]; + int len; + if (!has_pid_permissions(ns, iter.task, 2)) + continue; - filp->f_pos = iter.tgid + TGID_OFFSET; - if (proc_pid_fill_cache(filp, dirent, __filldir, iter) < 0) { + len = snprintf(name, sizeof(name), "%d", iter.tgid); + ctx->pos = iter.tgid + TGID_OFFSET; + if (!proc_fill_cache(file, ctx, name, len, + proc_pid_instantiate, iter.task, NULL)) { put_task_struct(iter.task); - goto out; + return 0; } } - filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; -out: + ctx->pos = PID_MAX_LIMIT + TGID_OFFSET; return 0; } @@ -3075,11 +3003,10 @@ static const struct pid_entry tid_base_stuff[] = { #endif }; -static int proc_tid_base_readdir(struct file * filp, - void * dirent, filldir_t filldir) +static int proc_tid_base_readdir(struct file *file, struct dir_context *ctx) { - return proc_pident_readdir(filp,dirent,filldir, - tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); + return proc_pident_readdir(file, ctx, + tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); } static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) @@ -3090,7 +3017,7 @@ static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *den static const struct file_operations proc_tid_base_operations = { .read = generic_read_dir, - .readdir = proc_tid_base_readdir, + .iterate = proc_tid_base_readdir, .llseek = default_llseek, }; @@ -3231,30 +3158,16 @@ static struct task_struct *next_tid(struct task_struct *start) return pos; } -static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, - struct task_struct *task, int tid) -{ - char name[PROC_NUMBUF]; - int len = snprintf(name, sizeof(name), "%d", tid); - return proc_fill_cache(filp, dirent, filldir, name, len, - proc_task_instantiate, task, NULL); -} - /* for the /proc/TGID/task/ directories */ -static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) +static int proc_task_readdir(struct file *file, struct dir_context *ctx) { - struct dentry *dentry = filp->f_path.dentry; - struct inode *inode = dentry->d_inode; struct task_struct *leader = NULL; - struct task_struct *task; - int retval = -ENOENT; - ino_t ino; - int tid; + struct task_struct *task = get_proc_task(file_inode(file)); struct pid_namespace *ns; + int tid; - task = get_proc_task(inode); if (!task) - goto out_no_task; + return -ENOENT; rcu_read_lock(); if (pid_alive(task)) { leader = task->group_leader; @@ -3263,46 +3176,36 @@ static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldi rcu_read_unlock(); put_task_struct(task); if (!leader) - goto out_no_task; - retval = 0; + return -ENOENT; - switch ((unsigned long)filp->f_pos) { - case 0: - ino = inode->i_ino; - if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) - goto out; - filp->f_pos++; - /* fall through */ - case 1: - ino = parent_ino(dentry); - if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) - goto out; - filp->f_pos++; - /* fall through */ - } + if (!dir_emit_dots(file, ctx)) + goto out; /* f_version caches the tgid value that the last readdir call couldn't * return. lseek aka telldir automagically resets f_version to 0. */ - ns = filp->f_dentry->d_sb->s_fs_info; - tid = (int)filp->f_version; - filp->f_version = 0; - for (task = first_tid(leader, tid, filp->f_pos - 2, ns); + ns = file->f_dentry->d_sb->s_fs_info; + tid = (int)file->f_version; + file->f_version = 0; + for (task = first_tid(leader, tid, ctx->pos - 2, ns); task; - task = next_tid(task), filp->f_pos++) { + task = next_tid(task), ctx->pos++) { + char name[PROC_NUMBUF]; + int len; tid = task_pid_nr_ns(task, ns); - if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { + len = snprintf(name, sizeof(name), "%d", tid); + if (!proc_fill_cache(file, ctx, name, len, + proc_task_instantiate, task, NULL)) { /* returning this tgid failed, save it as the first * pid for the next readir call */ - filp->f_version = (u64)tid; + file->f_version = (u64)tid; put_task_struct(task); break; } } out: put_task_struct(leader); -out_no_task: - return retval; + return 0; } static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) @@ -3328,6 +3231,6 @@ static const struct inode_operations proc_task_inode_operations = { static const struct file_operations proc_task_operations = { .read = generic_read_dir, - .readdir = proc_task_readdir, + .iterate = proc_task_readdir, .llseek = default_llseek, }; 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