From: Alexey Dobriyan <adobriyan@xxxxxxxxx> Subject: proc: decouple proc from VFS with "struct proc_ops" Currently core /proc code uses "struct file_operations" for custom hooks, however, VFS doesn't directly call them. Every time VFS expands file_operations hook set, /proc code bloats for no reason. Introduce "struct proc_ops" which contains only those hooks which /proc allows to call into (open, release, read, write, ioctl, mmap, poll). It doesn't contain module pointer as well. Save ~184 bytes per usage: add/remove: 26/26 grow/shrink: 1/4 up/down: 1922/-6674 (-4752) Function old new delta sysvipc_proc_ops - 72 +72 ... config_gz_proc_ops - 72 +72 proc_get_inode 289 339 +50 proc_reg_get_unmapped_area 110 107 -3 close_pdeo 227 224 -3 proc_reg_open 289 284 -5 proc_create_data 60 53 -7 rt_cpu_seq_fops 256 - -256 ... default_affinity_proc_fops 256 - -256 Total: Before=5430095, After=5425343, chg -0.09% Link: http://lkml.kernel.org/r/20191225172228.GA13378@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/generic.c | 38 +++++++++---------- fs/proc/inode.c | 76 +++++++++++++++++++------------------- fs/proc/internal.h | 5 ++ fs/proc/proc_net.c | 32 ++++++++-------- fs/proc/proc_sysctl.c | 2 - fs/proc/root.c | 2 - include/linux/proc_fs.h | 23 +++++++++-- 7 files changed, 98 insertions(+), 80 deletions(-) --- a/fs/proc/generic.c~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/generic.c @@ -473,7 +473,7 @@ struct proc_dir_entry *proc_mkdir_data(c ent = __proc_create(&parent, name, S_IFDIR | mode, 2); if (ent) { ent->data = data; - ent->proc_fops = &proc_dir_operations; + ent->proc_dir_ops = &proc_dir_operations; ent->proc_iops = &proc_dir_inode_operations; ent = proc_register(parent, ent); } @@ -503,7 +503,7 @@ struct proc_dir_entry *proc_create_mount ent = __proc_create(&parent, name, mode, 2); if (ent) { ent->data = NULL; - ent->proc_fops = NULL; + ent->proc_dir_ops = NULL; ent->proc_iops = NULL; ent = proc_register(parent, ent); } @@ -533,25 +533,23 @@ struct proc_dir_entry *proc_create_reg(c struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, struct proc_dir_entry *parent, - const struct file_operations *proc_fops, void *data) + const struct proc_ops *proc_ops, void *data) { struct proc_dir_entry *p; - BUG_ON(proc_fops == NULL); - p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; - p->proc_fops = proc_fops; + p->proc_ops = proc_ops; return proc_register(parent, p); } EXPORT_SYMBOL(proc_create_data); struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, - const struct file_operations *proc_fops) + const struct proc_ops *proc_ops) { - return proc_create_data(name, mode, parent, proc_fops, NULL); + return proc_create_data(name, mode, parent, proc_ops, NULL); } EXPORT_SYMBOL(proc_create); @@ -573,11 +571,11 @@ static int proc_seq_release(struct inode return seq_release(inode, file); } -static const struct file_operations proc_seq_fops = { - .open = proc_seq_open, - .read = seq_read, - .llseek = seq_lseek, - .release = proc_seq_release, +static const struct proc_ops proc_seq_ops = { + .proc_open = proc_seq_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = proc_seq_release, }; struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode, @@ -589,7 +587,7 @@ struct proc_dir_entry *proc_create_seq_p p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; - p->proc_fops = &proc_seq_fops; + p->proc_ops = &proc_seq_ops; p->seq_ops = ops; p->state_size = state_size; return proc_register(parent, p); @@ -603,11 +601,11 @@ static int proc_single_open(struct inode return single_open(file, de->single_show, de->data); } -static const struct file_operations proc_single_fops = { - .open = proc_single_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, +static const struct proc_ops proc_single_ops = { + .proc_open = proc_single_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = single_release, }; struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode, @@ -619,7 +617,7 @@ struct proc_dir_entry *proc_create_singl p = proc_create_reg(name, mode, &parent, data); if (!p) return NULL; - p->proc_fops = &proc_single_fops; + p->proc_ops = &proc_single_ops; p->single_show = show; return proc_register(parent, p); } --- a/fs/proc/inode.c~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/inode.c @@ -163,7 +163,7 @@ static void close_pdeo(struct proc_dir_e pdeo->closing = true; spin_unlock(&pde->pde_unload_lock); file = pdeo->file; - pde->proc_fops->release(file_inode(file), file); + pde->proc_ops->proc_release(file_inode(file), file); spin_lock(&pde->pde_unload_lock); /* After ->release. */ list_del(&pdeo->lh); @@ -200,12 +200,12 @@ static loff_t proc_reg_llseek(struct fil struct proc_dir_entry *pde = PDE(file_inode(file)); loff_t rv = -EINVAL; if (use_pde(pde)) { - typeof_member(struct file_operations, llseek) llseek; + typeof_member(struct proc_ops, proc_lseek) lseek; - llseek = pde->proc_fops->llseek; - if (!llseek) - llseek = default_llseek; - rv = llseek(file, offset, whence); + lseek = pde->proc_ops->proc_lseek; + if (!lseek) + lseek = default_llseek; + rv = lseek(file, offset, whence); unuse_pde(pde); } return rv; @@ -216,9 +216,9 @@ static ssize_t proc_reg_read(struct file struct proc_dir_entry *pde = PDE(file_inode(file)); ssize_t rv = -EIO; if (use_pde(pde)) { - typeof_member(struct file_operations, read) read; + typeof_member(struct proc_ops, proc_read) read; - read = pde->proc_fops->read; + read = pde->proc_ops->proc_read; if (read) rv = read(file, buf, count, ppos); unuse_pde(pde); @@ -231,9 +231,9 @@ static ssize_t proc_reg_write(struct fil struct proc_dir_entry *pde = PDE(file_inode(file)); ssize_t rv = -EIO; if (use_pde(pde)) { - typeof_member(struct file_operations, write) write; + typeof_member(struct proc_ops, proc_write) write; - write = pde->proc_fops->write; + write = pde->proc_ops->proc_write; if (write) rv = write(file, buf, count, ppos); unuse_pde(pde); @@ -246,9 +246,9 @@ static __poll_t proc_reg_poll(struct fil struct proc_dir_entry *pde = PDE(file_inode(file)); __poll_t rv = DEFAULT_POLLMASK; if (use_pde(pde)) { - typeof_member(struct file_operations, poll) poll; + typeof_member(struct proc_ops, proc_poll) poll; - poll = pde->proc_fops->poll; + poll = pde->proc_ops->proc_poll; if (poll) rv = poll(file, pts); unuse_pde(pde); @@ -261,9 +261,9 @@ static long proc_reg_unlocked_ioctl(stru struct proc_dir_entry *pde = PDE(file_inode(file)); long rv = -ENOTTY; if (use_pde(pde)) { - typeof_member(struct file_operations, unlocked_ioctl) ioctl; + typeof_member(struct proc_ops, proc_ioctl) ioctl; - ioctl = pde->proc_fops->unlocked_ioctl; + ioctl = pde->proc_ops->proc_ioctl; if (ioctl) rv = ioctl(file, cmd, arg); unuse_pde(pde); @@ -277,9 +277,9 @@ static long proc_reg_compat_ioctl(struct struct proc_dir_entry *pde = PDE(file_inode(file)); long rv = -ENOTTY; if (use_pde(pde)) { - typeof_member(struct file_operations, compat_ioctl) compat_ioctl; + typeof_member(struct proc_ops, proc_compat_ioctl) compat_ioctl; - compat_ioctl = pde->proc_fops->compat_ioctl; + compat_ioctl = pde->proc_ops->proc_compat_ioctl; if (compat_ioctl) rv = compat_ioctl(file, cmd, arg); unuse_pde(pde); @@ -293,9 +293,9 @@ static int proc_reg_mmap(struct file *fi struct proc_dir_entry *pde = PDE(file_inode(file)); int rv = -EIO; if (use_pde(pde)) { - typeof_member(struct file_operations, mmap) mmap; + typeof_member(struct proc_ops, proc_mmap) mmap; - mmap = pde->proc_fops->mmap; + mmap = pde->proc_ops->proc_mmap; if (mmap) rv = mmap(file, vma); unuse_pde(pde); @@ -312,9 +312,9 @@ proc_reg_get_unmapped_area(struct file * unsigned long rv = -EIO; if (use_pde(pde)) { - typeof_member(struct file_operations, get_unmapped_area) get_area; + typeof_member(struct proc_ops, proc_get_unmapped_area) get_area; - get_area = pde->proc_fops->get_unmapped_area; + get_area = pde->proc_ops->proc_get_unmapped_area; #ifdef CONFIG_MMU if (!get_area) get_area = current->mm->get_unmapped_area; @@ -333,8 +333,8 @@ static int proc_reg_open(struct inode *i { struct proc_dir_entry *pde = PDE(inode); int rv = 0; - typeof_member(struct file_operations, open) open; - typeof_member(struct file_operations, release) release; + typeof_member(struct proc_ops, proc_open) open; + typeof_member(struct proc_ops, proc_release) release; struct pde_opener *pdeo; /* @@ -351,7 +351,7 @@ static int proc_reg_open(struct inode *i if (!use_pde(pde)) return -ENOENT; - release = pde->proc_fops->release; + release = pde->proc_ops->proc_release; if (release) { pdeo = kmem_cache_alloc(pde_opener_cache, GFP_KERNEL); if (!pdeo) { @@ -360,7 +360,7 @@ static int proc_reg_open(struct inode *i } } - open = pde->proc_fops->open; + open = pde->proc_ops->proc_open; if (open) rv = open(inode, file); @@ -468,21 +468,23 @@ struct inode *proc_get_inode(struct supe inode->i_size = de->size; if (de->nlink) set_nlink(inode, de->nlink); - WARN_ON(!de->proc_iops); - inode->i_op = de->proc_iops; - if (de->proc_fops) { - if (S_ISREG(inode->i_mode)) { + + if (S_ISREG(inode->i_mode)) { + inode->i_op = de->proc_iops; + inode->i_fop = &proc_reg_file_ops; #ifdef CONFIG_COMPAT - if (!de->proc_fops->compat_ioctl) - inode->i_fop = - &proc_reg_file_ops_no_compat; - else -#endif - inode->i_fop = &proc_reg_file_ops; - } else { - inode->i_fop = de->proc_fops; + if (!de->proc_ops->proc_compat_ioctl) { + inode->i_fop = &proc_reg_file_ops_no_compat; } - } +#endif + } else if (S_ISDIR(inode->i_mode)) { + inode->i_op = de->proc_iops; + inode->i_fop = de->proc_dir_ops; + } else if (S_ISLNK(inode->i_mode)) { + inode->i_op = de->proc_iops; + inode->i_fop = NULL; + } else + BUG(); } else pde_put(de); return inode; --- a/fs/proc/internal.h~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/internal.h @@ -39,7 +39,10 @@ struct proc_dir_entry { spinlock_t pde_unload_lock; struct completion *pde_unload_completion; const struct inode_operations *proc_iops; - const struct file_operations *proc_fops; + union { + const struct proc_ops *proc_ops; + const struct file_operations *proc_dir_ops; + }; const struct dentry_operations *proc_dops; union { const struct seq_operations *seq_ops; --- a/fs/proc/proc_net.c~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/proc_net.c @@ -90,12 +90,12 @@ static int seq_release_net(struct inode return 0; } -static const struct file_operations proc_net_seq_fops = { - .open = seq_open_net, - .read = seq_read, - .write = proc_simple_write, - .llseek = seq_lseek, - .release = seq_release_net, +static const struct proc_ops proc_net_seq_ops = { + .proc_open = seq_open_net, + .proc_read = seq_read, + .proc_write = proc_simple_write, + .proc_lseek = seq_lseek, + .proc_release = seq_release_net, }; struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode, @@ -108,7 +108,7 @@ struct proc_dir_entry *proc_create_net_d if (!p) return NULL; pde_force_lookup(p); - p->proc_fops = &proc_net_seq_fops; + p->proc_ops = &proc_net_seq_ops; p->seq_ops = ops; p->state_size = state_size; return proc_register(parent, p); @@ -152,7 +152,7 @@ struct proc_dir_entry *proc_create_net_d if (!p) return NULL; pde_force_lookup(p); - p->proc_fops = &proc_net_seq_fops; + p->proc_ops = &proc_net_seq_ops; p->seq_ops = ops; p->state_size = state_size; p->write = write; @@ -183,12 +183,12 @@ static int single_release_net(struct ino return single_release(ino, f); } -static const struct file_operations proc_net_single_fops = { - .open = single_open_net, - .read = seq_read, - .write = proc_simple_write, - .llseek = seq_lseek, - .release = single_release_net, +static const struct proc_ops proc_net_single_ops = { + .proc_open = single_open_net, + .proc_read = seq_read, + .proc_write = proc_simple_write, + .proc_lseek = seq_lseek, + .proc_release = single_release_net, }; struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode, @@ -201,7 +201,7 @@ struct proc_dir_entry *proc_create_net_s if (!p) return NULL; pde_force_lookup(p); - p->proc_fops = &proc_net_single_fops; + p->proc_ops = &proc_net_single_ops; p->single_show = show; return proc_register(parent, p); } @@ -244,7 +244,7 @@ struct proc_dir_entry *proc_create_net_s if (!p) return NULL; pde_force_lookup(p); - p->proc_fops = &proc_net_single_fops; + p->proc_ops = &proc_net_single_ops; p->single_show = show; p->write = write; return proc_register(parent, p); --- a/fs/proc/proc_sysctl.c~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/proc_sysctl.c @@ -1720,7 +1720,7 @@ int __init proc_sys_init(void) proc_sys_root = proc_mkdir("sys", NULL); proc_sys_root->proc_iops = &proc_sys_dir_operations; - proc_sys_root->proc_fops = &proc_sys_dir_file_operations; + proc_sys_root->proc_dir_ops = &proc_sys_dir_file_operations; proc_sys_root->nlink = 0; return sysctl_init(); --- a/fs/proc/root.c~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/fs/proc/root.c @@ -292,7 +292,7 @@ struct proc_dir_entry proc_root = { .nlink = 2, .refcnt = REFCOUNT_INIT(1), .proc_iops = &proc_root_inode_operations, - .proc_fops = &proc_root_operations, + .proc_dir_ops = &proc_root_operations, .parent = &proc_root, .subdir = RB_ROOT, .name = "/proc", --- a/include/linux/proc_fs.h~proc-decouple-proc-from-vfs-with-struct-proc_ops +++ a/include/linux/proc_fs.h @@ -12,6 +12,21 @@ struct proc_dir_entry; struct seq_file; struct seq_operations; +struct proc_ops { + int (*proc_open)(struct inode *, struct file *); + ssize_t (*proc_read)(struct file *, char __user *, size_t, loff_t *); + ssize_t (*proc_write)(struct file *, const char __user *, size_t, loff_t *); + loff_t (*proc_lseek)(struct file *, loff_t, int); + int (*proc_release)(struct inode *, struct file *); + __poll_t (*proc_poll)(struct file *, struct poll_table_struct *); + long (*proc_ioctl)(struct file *, unsigned int, unsigned long); +#ifdef CONFIG_COMPAT + long (*proc_compat_ioctl)(struct file *, unsigned int, unsigned long); +#endif + int (*proc_mmap)(struct file *, struct vm_area_struct *); + unsigned long (*proc_get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); +}; + #ifdef CONFIG_PROC_FS typedef int (*proc_write_t)(struct file *, char *, size_t); @@ -43,10 +58,10 @@ struct proc_dir_entry *proc_create_singl extern struct proc_dir_entry *proc_create_data(const char *, umode_t, struct proc_dir_entry *, - const struct file_operations *, + const struct proc_ops *, void *); -struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct file_operations *proc_fops); +struct proc_dir_entry *proc_create(const char *name, umode_t mode, struct proc_dir_entry *parent, const struct proc_ops *proc_ops); extern void proc_set_size(struct proc_dir_entry *, loff_t); extern void proc_set_user(struct proc_dir_entry *, kuid_t, kgid_t); extern void *PDE_DATA(const struct inode *); @@ -108,8 +123,8 @@ static inline struct proc_dir_entry *pro #define proc_create_seq(name, mode, parent, ops) ({NULL;}) #define proc_create_single(name, mode, parent, show) ({NULL;}) #define proc_create_single_data(name, mode, parent, show, data) ({NULL;}) -#define proc_create(name, mode, parent, proc_fops) ({NULL;}) -#define proc_create_data(name, mode, parent, proc_fops, data) ({NULL;}) +#define proc_create(name, mode, parent, proc_ops) ({NULL;}) +#define proc_create_data(name, mode, parent, proc_ops, data) ({NULL;}) static inline void proc_set_size(struct proc_dir_entry *de, loff_t size) {} static inline void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) {} _
