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author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 09:03:55 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-05-20 09:03:55 -0700 |
commit | 46ee9645094ad1eb5b4888882ecaa1fb87dcd2a3 (patch) | |
tree | d0a48e993568b6a2415cfc21fc06eaa2fd886429 /kernel/power/user.c | |
parent | fa5312d9e87e7222c6c384c4e930dc149bc1178d (diff) | |
parent | 25f3a5a2854dce8b8413fd24cc9d5b9e3632be54 (diff) | |
download | linux-46ee9645094ad1eb5b4888882ecaa1fb87dcd2a3.tar.bz2 |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
PM: PM QOS update fix
Freezer / cgroup freezer: Update stale locking comments
PM / platform_bus: Allow runtime PM by default
i2c: Fix bus-level power management callbacks
PM QOS update
PM / Hibernate: Fix block_io.c printk warning
PM / Hibernate: Group swap ops
PM / Hibernate: Move the first_sector out of swsusp_write
PM / Hibernate: Separate block_io
PM / Hibernate: Snapshot cleanup
FS / libfs: Implement simple_write_to_buffer
PM / Hibernate: document open(/dev/snapshot) side effects
PM / Runtime: Add sysfs debug files
PM: Improve device power management document
PM: Update device power management document
PM: Allow runtime_suspend methods to call pm_schedule_suspend()
PM: pm_wakeup - switch to using bool
Diffstat (limited to 'kernel/power/user.c')
-rw-r--r-- | kernel/power/user.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/kernel/power/user.c b/kernel/power/user.c index a8c96212bc1b..e819e17877ca 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -151,6 +151,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, { struct snapshot_data *data; ssize_t res; + loff_t pg_offp = *offp & ~PAGE_MASK; mutex_lock(&pm_mutex); @@ -159,14 +160,19 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, res = -ENODATA; goto Unlock; } - res = snapshot_read_next(&data->handle, count); - if (res > 0) { - if (copy_to_user(buf, data_of(data->handle), res)) - res = -EFAULT; - else - *offp = data->handle.offset; + if (!pg_offp) { /* on page boundary? */ + res = snapshot_read_next(&data->handle); + if (res <= 0) + goto Unlock; + } else { + res = PAGE_SIZE - pg_offp; } + res = simple_read_from_buffer(buf, count, &pg_offp, + data_of(data->handle), res); + if (res > 0) + *offp += res; + Unlock: mutex_unlock(&pm_mutex); @@ -178,18 +184,25 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, { struct snapshot_data *data; ssize_t res; + loff_t pg_offp = *offp & ~PAGE_MASK; mutex_lock(&pm_mutex); data = filp->private_data; - res = snapshot_write_next(&data->handle, count); - if (res > 0) { - if (copy_from_user(data_of(data->handle), buf, res)) - res = -EFAULT; - else - *offp = data->handle.offset; + + if (!pg_offp) { + res = snapshot_write_next(&data->handle); + if (res <= 0) + goto unlock; + } else { + res = PAGE_SIZE - pg_offp; } + res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp, + buf, count); + if (res > 0) + *offp += res; +unlock: mutex_unlock(&pm_mutex); return res; |