diff options
Diffstat (limited to 'fs/read_write.c')
| -rw-r--r-- | fs/read_write.c | 315 |
1 files changed, 258 insertions, 57 deletions
diff --git a/fs/read_write.c b/fs/read_write.c index e6ddc8dceb9..03430008704 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -9,6 +9,7 @@ #include <linux/fcntl.h> #include <linux/file.h> #include <linux/uio.h> +#include <linux/aio.h> #include <linux/fsnotify.h> #include <linux/security.h> #include <linux/export.h> @@ -16,12 +17,15 @@ #include <linux/pagemap.h> #include <linux/splice.h> #include <linux/compat.h> -#include "read_write.h" #include "internal.h" #include <asm/uaccess.h> #include <asm/unistd.h> +typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *); +typedef ssize_t (*iov_fn_t)(struct kiocb *, const struct iovec *, + unsigned long, loff_t); + const struct file_operations generic_ro_fops = { .llseek = generic_file_llseek, .read = do_sync_read, @@ -128,7 +132,7 @@ EXPORT_SYMBOL(generic_file_llseek_size); * * This is a generic implemenation of ->llseek useable for all normal local * filesystems. It just updates the file offset to the value specified by - * @offset and @whence under i_mutex. + * @offset and @whence. */ loff_t generic_file_llseek(struct file *file, loff_t offset, int whence) { @@ -326,16 +330,6 @@ int rw_verify_area(int read_write, struct file *file, loff_t *ppos, size_t count return count > MAX_RW_COUNT ? MAX_RW_COUNT : count; } -static void wait_on_retry_sync_kiocb(struct kiocb *iocb) -{ - set_current_state(TASK_UNINTERRUPTIBLE); - if (!kiocbIsKicked(iocb)) - schedule(); - else - kiocbClearKicked(iocb); - __set_current_state(TASK_RUNNING); -} - 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 }; @@ -347,13 +341,7 @@ ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *pp kiocb.ki_left = len; kiocb.ki_nbytes = len; - for (;;) { - ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); - if (ret != -EIOCBRETRY) - break; - wait_on_retry_sync_kiocb(&kiocb); - } - + ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos); if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; @@ -403,13 +391,7 @@ ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, lof kiocb.ki_left = len; kiocb.ki_nbytes = len; - for (;;) { - ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); - if (ret != -EIOCBRETRY) - break; - wait_on_retry_sync_kiocb(&kiocb); - } - + ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos); if (-EIOCBQUEUED == ret) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; @@ -459,6 +441,7 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_ ret = rw_verify_area(WRITE, file, pos, count); if (ret >= 0) { count = ret; + file_start_write(file); if (file->f_op->write) ret = file->f_op->write(file, buf, count, pos); else @@ -468,6 +451,7 @@ ssize_t vfs_write(struct file *file, const char __user *buf, size_t count, loff_ add_wchar(current, ret); } inc_syscw(current); + file_end_write(file); } return ret; @@ -515,8 +499,8 @@ SYSCALL_DEFINE3(write, unsigned int, fd, const char __user *, buf, return ret; } -SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf, - size_t count, loff_t pos) +SYSCALL_DEFINE4(pread64, unsigned int, fd, char __user *, buf, + size_t, count, loff_t, pos) { struct fd f; ssize_t ret = -EBADF; @@ -534,17 +518,9 @@ SYSCALL_DEFINE(pread64)(unsigned int fd, char __user *buf, return ret; } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_pread64(long fd, long buf, long count, loff_t pos) -{ - return SYSC_pread64((unsigned int) fd, (char __user *) buf, - (size_t) count, pos); -} -SYSCALL_ALIAS(sys_pread64, SyS_pread64); -#endif -SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf, - size_t count, loff_t pos) +SYSCALL_DEFINE4(pwrite64, unsigned int, fd, const char __user *, buf, + size_t, count, loff_t, pos) { struct fd f; ssize_t ret = -EBADF; @@ -562,14 +538,6 @@ SYSCALL_DEFINE(pwrite64)(unsigned int fd, const char __user *buf, return ret; } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_pwrite64(long fd, long buf, long count, loff_t pos) -{ - return SYSC_pwrite64((unsigned int) fd, (const char __user *) buf, - (size_t) count, pos); -} -SYSCALL_ALIAS(sys_pwrite64, SyS_pwrite64); -#endif /* * Reduce an iovec's length in-place. Return the resulting number of segments @@ -592,7 +560,7 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) } EXPORT_SYMBOL(iov_shorten); -ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, +static 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; @@ -603,13 +571,7 @@ ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, 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); - } - + ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos); if (ret == -EIOCBQUEUED) ret = wait_on_sync_kiocb(&kiocb); *ppos = kiocb.ki_pos; @@ -617,7 +579,7 @@ ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov, } /* Do it by hand, with file-ops */ -ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov, +static 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; @@ -759,6 +721,7 @@ static ssize_t do_readv_writev(int type, struct file *file, } else { fn = (io_fn_t)file->f_op->write; fnv = file->f_op->aio_write; + file_start_write(file); } if (fnv) @@ -767,6 +730,9 @@ static ssize_t do_readv_writev(int type, struct file *file, else ret = do_loop_readv_writev(file, iov, nr_segs, pos, fn); + if (type != READ) + file_end_write(file); + out: if (iov != iovstack) kfree(iov); @@ -897,8 +863,203 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, return ret; } -ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, size_t count, - loff_t max) +#ifdef CONFIG_COMPAT + +static ssize_t compat_do_readv_writev(int type, struct file *file, + const struct compat_iovec __user *uvector, + unsigned long nr_segs, loff_t *pos) +{ + compat_ssize_t tot_len; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + ssize_t ret; + io_fn_t fn; + iov_fn_t fnv; + + ret = -EINVAL; + if (!file->f_op) + goto out; + + ret = -EFAULT; + if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector))) + goto out; + + ret = compat_rw_copy_check_uvector(type, uvector, nr_segs, + UIO_FASTIOV, iovstack, &iov); + if (ret <= 0) + goto out; + + tot_len = ret; + ret = rw_verify_area(type, file, pos, tot_len); + if (ret < 0) + goto out; + + fnv = NULL; + if (type == READ) { + fn = file->f_op->read; + fnv = file->f_op->aio_read; + } else { + fn = (io_fn_t)file->f_op->write; + fnv = file->f_op->aio_write; + file_start_write(file); + } + + 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 (type != READ) + file_end_write(file); + +out: + if (iov != iovstack) + kfree(iov); + if ((ret + (type == READ)) > 0) { + if (type == READ) + fsnotify_access(file); + else + fsnotify_modify(file); + } + return ret; +} + +static size_t compat_readv(struct file *file, + const struct compat_iovec __user *vec, + unsigned long vlen, loff_t *pos) +{ + ssize_t ret = -EBADF; + + if (!(file->f_mode & FMODE_READ)) + goto out; + + ret = -EINVAL; + if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read)) + goto out; + + ret = compat_do_readv_writev(READ, file, vec, vlen, pos); + +out: + if (ret > 0) + add_rchar(current, ret); + inc_syscr(current); + return ret; +} + +COMPAT_SYSCALL_DEFINE3(readv, unsigned long, fd, + const struct compat_iovec __user *,vec, + unsigned long, vlen) +{ + struct fd f = fdget(fd); + ssize_t ret; + loff_t pos; + + if (!f.file) + return -EBADF; + pos = f.file->f_pos; + ret = compat_readv(f.file, vec, vlen, &pos); + f.file->f_pos = pos; + fdput(f); + return ret; +} + +COMPAT_SYSCALL_DEFINE4(preadv64, unsigned long, fd, + const struct compat_iovec __user *,vec, + unsigned long, vlen, loff_t, pos) +{ + struct fd f; + ssize_t ret; + + if (pos < 0) + return -EINVAL; + f = fdget(fd); + if (!f.file) + return -EBADF; + ret = -ESPIPE; + if (f.file->f_mode & FMODE_PREAD) + ret = compat_readv(f.file, vec, vlen, &pos); + fdput(f); + return ret; +} + +COMPAT_SYSCALL_DEFINE5(preadv, unsigned long, fd, + const struct compat_iovec __user *,vec, + unsigned long, vlen, u32, pos_low, u32, pos_high) +{ + loff_t pos = ((loff_t)pos_high << 32) | pos_low; + return compat_sys_preadv64(fd, vec, vlen, pos); +} + +static size_t compat_writev(struct file *file, + const struct compat_iovec __user *vec, + unsigned long vlen, loff_t *pos) +{ + ssize_t ret = -EBADF; + + if (!(file->f_mode & FMODE_WRITE)) + goto out; + + ret = -EINVAL; + if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write)) + goto out; + + ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); + +out: + if (ret > 0) + add_wchar(current, ret); + inc_syscw(current); + return ret; +} + +COMPAT_SYSCALL_DEFINE3(writev, unsigned long, fd, + const struct compat_iovec __user *, vec, + unsigned long, vlen) +{ + struct fd f = fdget(fd); + ssize_t ret; + loff_t pos; + + if (!f.file) + return -EBADF; + pos = f.file->f_pos; + ret = compat_writev(f.file, vec, vlen, &pos); + f.file->f_pos = pos; + fdput(f); + return ret; +} + +COMPAT_SYSCALL_DEFINE4(pwritev64, unsigned long, fd, + const struct compat_iovec __user *,vec, + unsigned long, vlen, loff_t, pos) +{ + struct fd f; + ssize_t ret; + + if (pos < 0) + return -EINVAL; + f = fdget(fd); + if (!f.file) + return -EBADF; + ret = -ESPIPE; + if (f.file->f_mode & FMODE_PWRITE) + ret = compat_writev(f.file, vec, vlen, &pos); + fdput(f); + return ret; +} + +COMPAT_SYSCALL_DEFINE5(pwritev, unsigned long, fd, + const struct compat_iovec __user *,vec, + unsigned long, vlen, u32, pos_low, u32, pos_high) +{ + loff_t pos = ((loff_t)pos_high << 32) | pos_low; + return compat_sys_pwritev64(fd, vec, vlen, pos); +} +#endif + +static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos, + size_t count, loff_t max) { struct fd in, out; struct inode *in_inode, *out_inode; @@ -1022,3 +1183,43 @@ SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, loff_t __user *, offset, si return do_sendfile(out_fd, in_fd, NULL, count, 0); } + +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE4(sendfile, int, out_fd, int, in_fd, + compat_off_t __user *, offset, compat_size_t, count) +{ + loff_t pos; + off_t off; + ssize_t ret; + + if (offset) { + if (unlikely(get_user(off, offset))) + return -EFAULT; + pos = off; + ret = do_sendfile(out_fd, in_fd, &pos, count, MAX_NON_LFS); + if (unlikely(put_user(pos, offset))) + return -EFAULT; + return ret; + } + + return do_sendfile(out_fd, in_fd, NULL, count, 0); +} + +COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd, + compat_loff_t __user *, offset, compat_size_t, count) +{ + loff_t pos; + ssize_t ret; + + if (offset) { + if (unlikely(copy_from_user(&pos, offset, sizeof(loff_t)))) + return -EFAULT; + ret = do_sendfile(out_fd, in_fd, &pos, count, 0); + if (unlikely(put_user(pos, offset))) + return -EFAULT; + return ret; + } + + return do_sendfile(out_fd, in_fd, NULL, count, 0); +} +#endif |