X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=fs%2Fread_write.c;h=4d03008f015b9ae6d2565cdbc179d034687c3d08;hb=5351fb106a84d6ac584c2501e3b335093d38a58c;hp=5bc0e9234f9d7c5dd21b1e244127fece7bfa905c;hpb=4e8f10b7ccf1c3c53a818a157962074a7340732e;p=powerpc.git diff --git a/fs/read_write.c b/fs/read_write.c index 5bc0e9234f..4d03008f01 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -15,13 +15,15 @@ #include #include #include +#include "read_write.h" #include #include const struct file_operations generic_ro_fops = { .llseek = generic_file_llseek, - .read = generic_file_read, + .read = do_sync_read, + .aio_read = generic_file_aio_read, .mmap = generic_file_readonly_mmap, .sendfile = generic_file_sendfile, }; @@ -35,10 +37,10 @@ loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) mutex_lock(&inode->i_mutex); switch (origin) { - case 2: + case SEEK_END: offset += inode->i_size; break; - case 1: + case SEEK_CUR: offset += file->f_pos; } retval = -EINVAL; @@ -61,14 +63,14 @@ loff_t remote_llseek(struct file *file, loff_t offset, int origin) lock_kernel(); switch (origin) { - case 2: - offset += i_size_read(file->f_dentry->d_inode); + case SEEK_END: + offset += i_size_read(file->f_path.dentry->d_inode); break; - case 1: + case SEEK_CUR: offset += file->f_pos; } retval = -EINVAL; - if (offset>=0 && offset<=file->f_dentry->d_inode->i_sb->s_maxbytes) { + if (offset>=0 && offset<=file->f_path.dentry->d_inode->i_sb->s_maxbytes) { if (offset != file->f_pos) { file->f_pos = offset; file->f_version = 0; @@ -92,10 +94,10 @@ loff_t default_llseek(struct file *file, loff_t offset, int origin) lock_kernel(); switch (origin) { - case 2: - offset += i_size_read(file->f_dentry->d_inode); + case SEEK_END: + offset += i_size_read(file->f_path.dentry->d_inode); break; - case 1: + case SEEK_CUR: offset += file->f_pos; } retval = -EINVAL; @@ -137,7 +139,7 @@ asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin) goto bad; retval = -EINVAL; - if (origin <= 2) { + if (origin <= SEEK_MAX) { loff_t res = vfs_llseek(file, offset, origin); retval = res; if (res != (loff_t)retval) @@ -164,7 +166,7 @@ asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high, goto bad; retval = -EINVAL; - if (origin > 2) + if (origin > SEEK_MAX) goto out_putf; offset = vfs_llseek(file, ((loff_t) offset_high << 32) | offset_low, @@ -195,13 +197,13 @@ int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count struct inode *inode; loff_t pos; + inode = file->f_path.dentry->d_inode; if (unlikely((ssize_t) count < 0)) goto Einval; pos = *ppos; if (unlikely((pos < 0) || (loff_t) (pos + count) < 0)) goto Einval; - inode = file->f_dentry->d_inode; if (unlikely(inode->i_flock && MANDATORY_LOCK(inode))) { int retval = locks_mandatory_area( read_write == READ ? FLOCK_VERIFY_READ : FLOCK_VERIFY_WRITE, @@ -227,14 +229,20 @@ static void wait_on_retry_sync_kiocb(struct kiocb *iocb) ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) { + struct iovec iov = { .iov_base = buf, .iov_len = len }; struct kiocb kiocb; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; - while (-EIOCBRETRY == - (ret = filp->f_op->aio_read(&kiocb, buf, len, kiocb.ki_pos))) + kiocb.ki_left = len; + + for (;;) { + ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); + if (ret != -EIOCBRETRY) + break; wait_on_retry_sync_kiocb(&kiocb); + } if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); @@ -265,10 +273,10 @@ ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) else ret = do_sync_read(file, buf, count, pos); if (ret > 0) { - fsnotify_access(file->f_dentry); - current->rchar += ret; + fsnotify_access(file->f_path.dentry); + add_rchar(current, ret); } - current->syscr++; + inc_syscr(current); } } @@ -279,14 +287,20 @@ EXPORT_SYMBOL(vfs_read); ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos) { + struct iovec iov = { .iov_base = (void __user *)buf, .iov_len = len }; struct kiocb kiocb; ssize_t ret; init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; - while (-EIOCBRETRY == - (ret = filp->f_op->aio_write(&kiocb, buf, len, kiocb.ki_pos))) + kiocb.ki_left = len; + + for (;;) { + ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); + if (ret != -EIOCBRETRY) + break; wait_on_retry_sync_kiocb(&kiocb); + } if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); @@ -317,10 +331,10 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_ else ret = do_sync_write(file, buf, count, pos); if (ret > 0) { - fsnotify_modify(file->f_dentry); - current->wchar += ret; + fsnotify_modify(file->f_path.dentry); + add_wchar(current, ret); } - current->syscw++; + inc_syscw(current); } } @@ -436,80 +450,155 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) return seg; } -EXPORT_SYMBOL(iov_shorten); +ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, + unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn) +{ + struct kiocb kiocb; + ssize_t ret; + + init_sync_kiocb(&kiocb, filp); + kiocb.ki_pos = *ppos; + kiocb.ki_left = len; + kiocb.ki_nbytes = len; + + for (;;) { + ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); + if (ret != -EIOCBRETRY) + break; + wait_on_retry_sync_kiocb(&kiocb); + } + + if (ret == -EIOCBQUEUED) + ret = wait_on_sync_kiocb(&kiocb); + *ppos = kiocb.ki_pos; + return ret; +} + +/* Do it by hand, with file-ops */ +ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, + unsigned long nr_segs, loff_t *ppos, io_fn_t fn) +{ + struct iovec *vector = iov; + ssize_t ret = 0; + + while (nr_segs > 0) { + void __user *base; + size_t len; + ssize_t nr; + + base = vector->iov_base; + len = vector->iov_len; + vector++; + nr_segs--; + + nr = fn(filp, base, len, ppos); + + if (nr < 0) { + if (!ret) + ret = nr; + break; + } + ret += nr; + if (nr != len) + break; + } + + return ret; +} /* A write operation does a read from user space and vice versa */ #define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) +ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector, + unsigned long nr_segs, unsigned long fast_segs, + struct iovec *fast_pointer, + struct iovec **ret_pointer) + { + unsigned long seg; + ssize_t ret; + struct iovec *iov = fast_pointer; + + /* + * SuS says "The readv() function *may* fail if the iovcnt argument + * was less than or equal to 0, or greater than {IOV_MAX}. Linux has + * traditionally returned zero for zero segments, so... + */ + if (nr_segs == 0) { + ret = 0; + goto out; + } + + /* + * First get the "struct iovec" from user memory and + * verify all the pointers + */ + if (nr_segs > UIO_MAXIOV) { + ret = -EINVAL; + goto out; + } + if (nr_segs > fast_segs) { + iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); + if (iov == NULL) { + ret = -ENOMEM; + goto out; + } + } + if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) { + ret = -EFAULT; + goto out; + } + + /* + * According to the Single Unix Specification we should return EINVAL + * if an element length is < 0 when cast to ssize_t or if the + * total length would overflow the ssize_t return value of the + * system call. + */ + ret = 0; + for (seg = 0; seg < nr_segs; seg++) { + void __user *buf = iov[seg].iov_base; + ssize_t len = (ssize_t)iov[seg].iov_len; + + /* see if we we're about to use an invalid len or if + * it's about to overflow ssize_t */ + if (len < 0 || (ret + len < ret)) { + ret = -EINVAL; + goto out; + } + if (unlikely(!access_ok(vrfy_dir(type), buf, len))) { + ret = -EFAULT; + goto out; + } + + ret += len; + } +out: + *ret_pointer = iov; + return ret; +} + static ssize_t do_readv_writev(int type, struct file *file, const struct iovec __user * uvector, unsigned long nr_segs, loff_t *pos) { - typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); - typedef ssize_t (*iov_fn_t)(struct file *, const struct iovec *, unsigned long, loff_t *); - size_t tot_len; struct iovec iovstack[UIO_FASTIOV]; - struct iovec *iov=iovstack, *vector; + struct iovec *iov = iovstack; ssize_t ret; - int seg; io_fn_t fn; iov_fn_t fnv; - /* - * SuS says "The readv() function *may* fail if the iovcnt argument - * was less than or equal to 0, or greater than {IOV_MAX}. Linux has - * traditionally returned zero for zero segments, so... - */ - ret = 0; - if (nr_segs == 0) + if (!file->f_op) { + ret = -EINVAL; goto out; + } - /* - * First get the "struct iovec" from user memory and - * verify all the pointers - */ - ret = -EINVAL; - if (nr_segs > UIO_MAXIOV) - goto out; - if (!file->f_op) - goto out; - if (nr_segs > UIO_FASTIOV) { - ret = -ENOMEM; - iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); - if (!iov) - goto out; - } - ret = -EFAULT; - if (copy_from_user(iov, uvector, nr_segs*sizeof(*uvector))) + ret = rw_copy_check_uvector(type, uvector, nr_segs, + ARRAY_SIZE(iovstack), iovstack, &iov); + if (ret <= 0) goto out; - /* - * Single unix specification: - * We should -EINVAL if an element length is not >= 0 and fitting an - * ssize_t. The total length is fitting an ssize_t - * - * Be careful here because iov_len is a size_t not an ssize_t - */ - tot_len = 0; - ret = -EINVAL; - for (seg = 0; seg < nr_segs; seg++) { - void __user *buf = iov[seg].iov_base; - ssize_t len = (ssize_t)iov[seg].iov_len; - - if (len < 0) /* size_t not fitting an ssize_t .. */ - goto out; - if (unlikely(!access_ok(vrfy_dir(type), buf, len))) - goto Efault; - tot_len += len; - if ((ssize_t)tot_len < 0) /* maths overflow on the ssize_t */ - goto out; - } - if (tot_len == 0) { - ret = 0; - goto out; - } - + tot_len = ret; ret = rw_verify_area(type, file, pos, tot_len); if (ret < 0) goto out; @@ -520,52 +609,28 @@ static ssize_t do_readv_writev(int type, struct file *file, fnv = NULL; if (type == READ) { fn = file->f_op->read; - fnv = file->f_op->readv; + fnv = file->f_op->aio_read; } else { fn = (io_fn_t)file->f_op->write; - fnv = file->f_op->writev; + fnv = file->f_op->aio_write; } - if (fnv) { - ret = fnv(file, iov, nr_segs, pos); - goto out; - } - - /* Do it by hand, with file-ops */ - ret = 0; - vector = iov; - while (nr_segs > 0) { - void __user * base; - size_t len; - ssize_t nr; - base = vector->iov_base; - len = vector->iov_len; - vector++; - nr_segs--; - - nr = fn(file, base, len, pos); + if (fnv) + ret = do_sync_readv_writev(file, iov, nr_segs, tot_len, + pos, fnv); + else + ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); - if (nr < 0) { - if (!ret) ret = nr; - break; - } - ret += nr; - if (nr != len) - break; - } out: if (iov != iovstack) kfree(iov); if ((ret + (type == READ)) > 0) { if (type == READ) - fsnotify_access(file->f_dentry); + fsnotify_access(file->f_path.dentry); else - fsnotify_modify(file->f_dentry); + fsnotify_modify(file->f_path.dentry); } return ret; -Efault: - ret = -EFAULT; - goto out; } ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, @@ -573,7 +638,7 @@ ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, { if (!(file->f_mode & FMODE_READ)) return -EBADF; - if (!file->f_op || (!file->f_op->readv && !file->f_op->read)) + if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) return -EINVAL; return do_readv_writev(READ, file, vec, vlen, pos); @@ -586,7 +651,7 @@ ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, { if (!(file->f_mode & FMODE_WRITE)) return -EBADF; - if (!file->f_op || (!file->f_op->writev && !file->f_op->write)) + if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) return -EINVAL; return do_readv_writev(WRITE, file, vec, vlen, pos); @@ -610,8 +675,8 @@ sys_readv(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) } if (ret > 0) - current->rchar += ret; - current->syscr++; + add_rchar(current, ret); + inc_syscr(current); return ret; } @@ -631,8 +696,8 @@ sys_writev(unsigned long fd, const struct iovec __user *vec, unsigned long vlen) } if (ret > 0) - current->wchar += ret; - current->syscw++; + add_wchar(current, ret); + inc_syscw(current); return ret; } @@ -655,7 +720,7 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, if (!(in_file->f_mode & FMODE_READ)) goto fput_in; retval = -EINVAL; - in_inode = in_file->f_dentry->d_inode; + in_inode = in_file->f_path.dentry->d_inode; if (!in_inode) goto fput_in; if (!in_file->f_op || !in_file->f_op->sendfile) @@ -687,7 +752,7 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, retval = -EINVAL; if (!out_file->f_op || !out_file->f_op->sendpage) goto fput_out; - out_inode = out_file->f_dentry->d_inode; + out_inode = out_file->f_path.dentry->d_inode; retval = rw_verify_area(WRITE, out_file, &out_file->f_pos, count); if (retval < 0) goto fput_out; @@ -714,12 +779,12 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, retval = in_file->f_op->sendfile(in_file, ppos, count, file_send_actor, out_file); if (retval > 0) { - current->rchar += retval; - current->wchar += retval; + add_rchar(current, retval); + add_wchar(current, retval); } - current->syscr++; - current->syscw++; + inc_syscr(current); + inc_syscw(current); if (*ppos > max) retval = -EOVERFLOW;