From 3eed13cc3beaa9ee07b126a662def88f7281394e Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Fri, 10 Aug 2007 14:32:34 +0200 Subject: [PATCH] [S390] vmur: diag14 only works with buffers below 2GB If memory buffers above 2GB are used, diagnose 14 raises a specification exception. This fix ensures that buffer allocation is done below the 2GB boundary. Signed-off-by: Michael Holzheu Signed-off-by: Martin Schwidefsky --- drivers/s390/char/vmur.c | 106 ++++++++++++++++++++++++++------------- 1 file changed, 70 insertions(+), 36 deletions(-) diff --git a/drivers/s390/char/vmur.c b/drivers/s390/char/vmur.c index a9d58629e7..04b19bdc09 100644 --- a/drivers/s390/char/vmur.c +++ b/drivers/s390/char/vmur.c @@ -472,7 +472,7 @@ static ssize_t diag14_read(struct file *file, char __user *ubuf, size_t count, return rc; len = min((size_t) PAGE_SIZE, count); - buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + buf = (char *) __get_free_page(GFP_KERNEL | GFP_DMA); if (!buf) return -ENOMEM; @@ -499,7 +499,7 @@ static ssize_t diag14_read(struct file *file, char __user *ubuf, size_t count, *offs += copied; rc = copied; fail: - kfree(buf); + free_page((unsigned long) buf); return rc; } @@ -542,63 +542,97 @@ static int diag_read_next_file_info(struct file_control_block *buf, int spid) } } -static int verify_device(struct urdev *urd) +static int verify_uri_device(struct urdev *urd) { - struct file_control_block fcb; + struct file_control_block *fcb; char *buf; int rc; + fcb = kmalloc(sizeof(*fcb), GFP_KERNEL | GFP_DMA); + if (!fcb) + return -ENOMEM; + + /* check for empty reader device (beginning of chain) */ + rc = diag_read_next_file_info(fcb, 0); + if (rc) + goto fail_free_fcb; + + /* if file is in hold status, we do not read it */ + if (fcb->file_stat & (FLG_SYSTEM_HOLD | FLG_USER_HOLD)) { + rc = -EPERM; + goto fail_free_fcb; + } + + /* open file on virtual reader */ + buf = (char *) __get_free_page(GFP_KERNEL | GFP_DMA); + if (!buf) { + rc = -ENOMEM; + goto fail_free_fcb; + } + rc = diag_read_file(urd->dev_id.devno, buf); + if ((rc != 0) && (rc != -ENODATA)) /* EOF does not hurt */ + goto fail_free_buf; + + /* check if the file on top of the queue is open now */ + rc = diag_read_next_file_info(fcb, 0); + if (rc) + goto fail_free_buf; + if (!(fcb->file_stat & FLG_IN_USE)) { + rc = -EMFILE; + goto fail_free_buf; + } + rc = 0; + +fail_free_buf: + free_page((unsigned long) buf); +fail_free_fcb: + kfree(fcb); + return rc; +} + +static int verify_device(struct urdev *urd) +{ switch (urd->class) { case DEV_CLASS_UR_O: return 0; /* no check needed here */ case DEV_CLASS_UR_I: - /* check for empty reader device (beginning of chain) */ - rc = diag_read_next_file_info(&fcb, 0); - if (rc) - return rc; - /* if file is in hold status, we do not read it */ - if (fcb.file_stat & (FLG_SYSTEM_HOLD | FLG_USER_HOLD)) - return -EPERM; - /* open file on virtual reader */ - buf = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!buf) - return -ENOMEM; - rc = diag_read_file(urd->dev_id.devno, buf); - kfree(buf); - if ((rc != 0) && (rc != -ENODATA)) /* EOF does not hurt */ - return rc; - /* check if the file on top of the queue is open now */ - rc = diag_read_next_file_info(&fcb, 0); - if (rc) - return rc; - if (!(fcb.file_stat & FLG_IN_USE)) - return -EMFILE; - return 0; + return verify_uri_device(urd); default: return -ENOTSUPP; } } -static int get_file_reclen(struct urdev *urd) +static int get_uri_file_reclen(struct urdev *urd) { - struct file_control_block fcb; + struct file_control_block *fcb; int rc; + fcb = kmalloc(sizeof(*fcb), GFP_KERNEL | GFP_DMA); + if (!fcb) + return -ENOMEM; + rc = diag_read_next_file_info(fcb, 0); + if (rc) + goto fail_free; + if (fcb->file_stat & FLG_CP_DUMP) + rc = 0; + else + rc = fcb->rec_len; + +fail_free: + kfree(fcb); + return rc; +} + +static int get_file_reclen(struct urdev *urd) +{ switch (urd->class) { case DEV_CLASS_UR_O: return 0; case DEV_CLASS_UR_I: - rc = diag_read_next_file_info(&fcb, 0); - if (rc) - return rc; - break; + return get_uri_file_reclen(urd); default: return -ENOTSUPP; } - if (fcb.file_stat & FLG_CP_DUMP) - return 0; - - return fcb.rec_len; } static int ur_open(struct inode *inode, struct file *file) -- 2.39.5