From 723a1d77431b0c568730ffac4dd0bcbbd3400031 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 19 Aug 2012 13:00:49 -0400 Subject: um: resurrect the right variant of mconsole_proc() Signed-off-by: Al Viro --- arch/um/drivers/mconsole_kern.c | 99 +++++++++-------------------------------- 1 file changed, 21 insertions(+), 78 deletions(-) diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index 664a60e8dfb4..495e5a725aa1 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -21,6 +21,9 @@ #include #include #include +#include +#include +#include #include #include @@ -118,90 +121,38 @@ void mconsole_log(struct mc_request *req) mconsole_reply(req, "", 0, 0); } -/* This is a more convoluted version of mconsole_proc, which has some stability - * problems; however, we need it fixed, because it is expected that UML users - * mount HPPFS instead of procfs on /proc. And we want mconsole_proc to still - * show the real procfs content, not the ones from hppfs.*/ -#if 0 void mconsole_proc(struct mc_request *req) { struct vfsmount *mnt = current->nsproxy->pid_ns->proc_mnt; - struct file *file; - int n; - char *ptr = req->request.data, *buf; - mm_segment_t old_fs = get_fs(); - - ptr += strlen("proc"); - ptr = skip_spaces(ptr); - - file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY); - if (IS_ERR(file)) { - mconsole_reply(req, "Failed to open file", 1, 0); - goto out; - } - - buf = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (buf == NULL) { - mconsole_reply(req, "Failed to allocate buffer", 1, 0); - goto out_fput; - } - - if (file->f_op->read) { - do { - loff_t pos; - set_fs(KERNEL_DS); - n = vfs_read(file, buf, PAGE_SIZE - 1, &pos); - file_pos_write(file, pos); - set_fs(old_fs); - if (n >= 0) { - buf[n] = '\0'; - mconsole_reply(req, buf, 0, (n > 0)); - } - else { - mconsole_reply(req, "Read of file failed", - 1, 0); - goto out_free; - } - } while (n > 0); - } - else mconsole_reply(req, "", 0, 0); - - out_free: - kfree(buf); - out_fput: - fput(file); - out: ; -} -#endif - -void mconsole_proc(struct mc_request *req) -{ - char path[64]; char *buf; int len; - int fd; + struct file *file; int first_chunk = 1; char *ptr = req->request.data; ptr += strlen("proc"); ptr = skip_spaces(ptr); - snprintf(path, sizeof(path), "/proc/%s", ptr); - fd = sys_open(path, 0, 0); - if (fd < 0) { + file = file_open_root(mnt->mnt_root, mnt, ptr, O_RDONLY); + if (IS_ERR(file)) { mconsole_reply(req, "Failed to open file", 1, 0); - printk(KERN_ERR "open %s: %d\n",path,fd); + printk(KERN_ERR "open /proc/%s: %ld\n", ptr, PTR_ERR(file)); goto out; } buf = kmalloc(PAGE_SIZE, GFP_KERNEL); if (buf == NULL) { mconsole_reply(req, "Failed to allocate buffer", 1, 0); - goto out_close; + goto out_fput; } - for (;;) { - len = sys_read(fd, buf, PAGE_SIZE-1); + do { + loff_t pos; + mm_segment_t old_fs = get_fs(); + set_fs(KERNEL_DS); + len = vfs_read(file, buf, PAGE_SIZE - 1, &pos); + set_fs(old_fs); + file->f_pos = pos; if (len < 0) { mconsole_reply(req, "Read of file failed", 1, 0); goto out_free; @@ -211,22 +162,14 @@ void mconsole_proc(struct mc_request *req) mconsole_reply(req, "\n", 0, 1); first_chunk = 0; } - if (len == PAGE_SIZE-1) { - buf[len] = '\0'; - mconsole_reply(req, buf, 0, 1); - } else { - buf[len] = '\0'; - mconsole_reply(req, buf, 0, 0); - break; - } - } - + buf[len] = '\0'; + mconsole_reply(req, buf, 0, (len > 0)); + } while (len > 0); out_free: kfree(buf); - out_close: - sys_close(fd); - out: - /* nothing */; + out_fput: + fput(file); + out: ; } #define UML_MCONSOLE_HELPTEXT \ -- cgit v1.2.3