lkml.org 
[lkml]   [2022]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCH v3] cachefiles: fix error return code in cachefiles_ondemand_copen()
    From
    Hi David,

    On 8/24/22 6:19 PM, David Howells wrote:
    > /* fail OPEN request if copen format is invalid */
    > ret = kstrtol(psize, 0, &size);
    > if (ret) {
    > req->error = ret;
    > goto out;
    > }
    >
    > /* fail OPEN request if daemon reports an error */
    > if (size < 0) {
    > if (!IS_ERR_VALUE(size))
    > ret = size = -EINVAL;
    > req->error = size;
    > goto out;
    > }
    >
    > Should ret get set to the error in size?


    The user daemon completes the OPEN request by replying with the "copen"
    command. The format of "copen" is like: "copen <id>,<cache_size>",
    where <cache_size> specifies the size of the backing file. Besides,
    <cache_size> is also reused for specifying the error code when the user
    daemon thinks it should fail the OPEN request. In this case, the OPEN
    request will fail, while the copen command (i.e.
    cachefiles_ondemand_copen()) shall return 0, since the format of the
    input "copen" command has no problem at all. After all, the error code
    inside <cache_size> is specified by the user daemon itself, and the fact
    that the OPEN request will fail totally lies in the expectation of the
    user daemon.


    On the other hand, cachefiles_ondemand_copen() needs to return error
    code when the user daemon specifies the "copen" command in a wrong
    format, e.g. specifying an invalid error code in <cache_size>. This is
    exactly what this patch fixes.


    --
    Thanks,
    Jingbo

    \
     
     \ /
      Last update: 2022-08-24 13:34    [W:2.381 / U:0.264 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site