add1aaeabe
For a long time people have complained about the limitations imposed by usbfs. URBs coming from userspace are not allowed to have transfer buffers larger than a more-or-less arbitrary maximum. While it is generally a good idea to avoid large transfer buffers (because the data has to be bounced to/from a contiguous kernel-space buffer), it's not the kernel's job to enforce such limits. Programs should be allowed to submit URBs as large as they like; if there isn't sufficient contiguous memory available then the submission will fail with a simple ENOMEM error. On the other hand, we would like to prevent programs from submitting a lot of small URBs and using up all the DMA-able kernel memory. To that end, this patch (as1497) replaces the old limits on individual transfer buffers with a single global limit on the total amount of memory in use by usbfs. The global limit is set to 16 MB as a nice compromise value: not too big, but large enough to hold about 300 ms of data for high-speed transfers. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| .. | ||
| buffer.c | ||
| config.c | ||
| devices.c | ||
| devio.c | ||
| driver.c | ||
| endpoint.c | ||
| file.c | ||
| generic.c | ||
| hcd-pci.c | ||
| hcd.c | ||
| hub.c | ||
| inode.c | ||
| Kconfig | ||
| Makefile | ||
| message.c | ||
| notify.c | ||
| otg_whitelist.h | ||
| quirks.c | ||
| sysfs.c | ||
| urb.c | ||
| usb.c | ||
| usb.h | ||